Home

Hardware Troubleshooting Techniques

1. Computer Management Local B c Partition Basic NTFS Healthy System 4 99 GB 2 63 GB E i System Tools 0 Simple Dynamic FAT Healthy 1 96 GB 1 58 GB E E Event Viewer Be Partition Basic FAT32 Healthy 2 87 GB 2 87 GB E System Information E W2POEM_EN Partition Basic OFS Healthy 360 MB ome E Performance Logs and Alerts G Shared Folders 4 Device Manager Local Users and Groups Disk 0 a E st Basic E G DAN E 7 87 GB 4 99 GB NTFS 2 87 GB FAT32 n Onine Healthy System Healthy I Disk Defragmenter Logical Drives gisk 1 E Removable Storage Dynamic D f Services and Applications 1 97 GB 1 97 GB FAT Online Healthy CDRom 2 W2POEM_EN 2 361 MB 361 MB COFS Online Healthy H Primary Partition i Simple Volume Figure 3 10 Windows 2000 Disk Management snap in Formatting Volumes in Windows 2000 and Windows XP Formatting a partition or volume prepares the logical structure to accept data by creating the file system in it If a partition or volume has not been formatted it does not contain a file system and it cannot be accessed through the operating system or any applications In the Windows 2000 and Windows XP environment you can perform many actions to initiate for matting including the following gt Use the Volume Creation Wizard in the Disk Management utility when the volume is created gt In the Disk Manag
2. 4 AT Power ATX Power KEY Supply Supply IPWR GOOD 43 Connector Connector SNARES Q iz D E Bilele MeN 5 v 2o A LB E a AT System Board ATX System Board Figure 3 3 DC voltage check As an approximate value is detected you can decrease the range setting to achieve a more accurate reading Most meters allow for overvoltage protec tion however it is still a good safety practice to decrease the range of the meter after you have achieved an initial value The second most popular test is the resistance or continuity test 184 Chapter 3 lt kAy Unlike voltage checks resistance checks are always made with power removed from AL Ni the system Failure to turn off the power when making resistance checks can cause seri ous damage to the meter and can pose a potential risk to the technician Resistance checks require that you electrically isolate the component being tested from the system For most circuit components this means desolder ing at least one end from the board The resistance check is very useful in isolating some types of problems in the system One of the main uses of the resistance function is to test fuses You must disconnect at least one end of the fuse from the system You should set the meter on the 1k ohm resistance setting If the fuse is good the meter should read near 0 ohms If it is bad the meter r
3. Hardware Troubleshooting Techniques You can use other at compatible commands to check the modem at the com mand prompt level The atL2 command sets the modem s output volume to medium to ensure it is not set too low to be heard If the modem dials but cannot connect to a remote station check the modem s Speed and DTR set tings Change the DTR setting by entering atapn gt n 0 The modem ignores the DTR line gt n 1 The modem goes to async command state when the DTR line goes off gt n 2 A DTR off condition switches the modem to the off hook state and back into command mode gt n 3 When the DTR line switches to off the modem is initialized If the modem connects but cannot communicate check the character framing parameter of the receiving modem and set the local modem to match Also match the terminal emulation of the local unit to that of the remote unit American National Standards Institute ANSI terminal emula tion is the most common Finally match the file transfer protocol to the other modem During a data transfer both modems monitor the signal level of the carrier to prevent the transfer of false data due to signal deterioration If the carrier signal strength drops below a predetermined threshold level or is lost for a given length of time one or both modems initiate automatic disconnect pro cedures Use the atot 7 command to disable call waiting if the transmission is fre quent
4. Hardware Troubleshooting Techniques Introduction This chapter contains information that applies to identifying and trouble shooting hardware problems Sorting Hardware Software Configuration Problems One of the first steps in troubleshooting a computer problem or any other programmable system problem is to determine whether the problem is due to a hardware failure or to faulty software In most PCs you can use a sig nificant event that occurs during the startup process as a key to separate hardware problems from software problems the single beep that most PCs produce between the end of the power on self test POST and the begin ning of the startup process Errors that occur or are displayed before this beep indicate that a hardware problem of some type exists Up to this point in the operation of the system only the BIOS and the basic system hardware have been active The operat ing system side of the system does not come into play until after the beep occurs 178 Chapter 3 If the system produces an error message such as The system has detected unstable RAM at location x or a beep code before the single beep occurs the system has found a problem with the hardware In this case a bad RAM memory device is indicated Typically if the startup process reaches the point at which the system s CMOS configuration information is displayed onscreen you can safely assume that no hardware configuration conflicts ex
5. lt ESC gt to Exit Figure 3 1 A typical software diagnostic main menu This menu is the gateway to information about the system s makeup and configuration as well as the entryway to the program s Advanced Diagnostic Test functions You can find utilities for performing low level formats on older hard drive types and for managing small computer system interface SCSI devices through this menu In addition options to print or show test results are available here as is the exit point from the program The most common software troubleshooting packages test the system s memory microprocessor keyboard display monitor and the disk drive s speed If at least the system s CPU disk drive and clock circuits are working you might be able to use one of these special software troubleshooting pack ages to help localize system failures They can prove especially helpful when trying to track down non heat related intermittent problems If a diagnostic program indicates that multiple items should be replaced replace the units one at a time until the unit starts up Then replace any units removed prior to the one that caused the system to start This process ensures that there are not multiple bad parts If you have replaced all the parts and the unit still does not function properly the diagnostic software is suspect 182 Chapter 3 Using a Multimeter in a PC A number of test instruments can help you isolate computer hardware p
6. 2 meters 6 feet but most speci fications usually state 1 meter as the maximum range All IrDA transfers are carried out in half duplex mode and must have a clear line of sight between the transmitter and receiver The receiver must be situated within 15 degrees of center with the line of transmission Therefore you should test a failing infrared connection by placing the infrared transceivers as close together as possible and straight inline with each other The properties of installed IrDA devices can be viewed through their entries in Device Manager Verify that the Enable Infrared communication check box is checked To engage support for infrared plug and play devices right click the Infrared icon on the taskbar Verify that the Enable Plug and Play option is checked It will only be available if the infrared and searching functions are enabled If the taskbar icon is not visible click the Infrared Monitor icon in Control Panel click the Preferences tab and select the Display the Infrared Monitor Icon on the Taskbar option Right click the Infrared icon on the taskbar to install software for an infrared device Verify that the Enable Plug and Play option is checked and verify that the new device is within range Windows also provides an Infrared Monitor utility that can be used to track the computer s activity When this utility is running it alerts you when infrared devices are within range of your computer by placing the Infra
7. Port ECP mode for proper operation In both cases the pro tocol must be set properly for the port and the device to carry out commu nications If serial or parallel port problems are occurring the CMOS configuration window displayed during the startup sequence is the first place to look Read the port assignments in the bootup window If the system has not detected the presence of the port hardware at this stage none of the more advanced levels will find it either If values for any of the physical ports installed in the system do not appear in this window check for improper port configuration Because the system has not loaded an operating system at the time the con figuration window appears the operating system cannot be a source of port problems at this time If all configuration settings for the ports appear cor rect assume that a hardware problem exists Basic Parallel Ports Run a software diagnostic package to narrow the possible problem causes This is not normally a problem because port failures generally do not affect the main components of the system Software diagnostic packages normally require you to place a loopback plug in the parallel port connector to run tests on the port The loopback plug simulates a printer device by redirect ing output signals from the port into port input pins You can use a live printer with the port for testing purposes however this action elevates the possibility that the printer might in
8. Safe Mode option This should load Windows with the standard 640 x 480 x 16 color VGA driver the most fundamental driver available for VGA monitors and should furnish a starting point for installing the correct driver for the moni tor being used After you have gained access to a usable display check the installed video drivers You can access the Windows video information through Device Manager From this utility select the Display Adapters entry from the list and double click the monitor icon that appears as a branch The adapter s Properties dialog box should open The Driver tab reveals the driver file in use If the video driver listed is not correct reload the correct driver Selecting the Resources tab displays the video adapter s register address ranges and the video memory address range as shown in Figure 3 9 You can manipulate these settings manually by clearing the Use Automatic Settings check box and then clicking the activated Change Settings button You also can obtain information about the monitor through the System icon System Properties 2 x General Device Manager Hardware Profiles Performance Candeias bulge SiS 5597 5598 Properties E x General Driver Resources Computer CDROM E Disk dives T SiS 5597 5598 a Display adapters a g M Use automatic settings Floppy disk controllers 89 Network adapters
9. and configuration settings appear correct and problems are occurring the modem hardware is experiencing a problem and it is necessary to exchange the modem card for a known good one With an external modem you can use the front panel lights as diagnostic tools to monitor its operation You can monitor the progress and handling of a call along with any errors that might occur Troubleshooting Sound Cards Most sound cards perform two separate functions The first is to play sound files the second is to record them You might need to troubleshoot problems for either function Sound Card Configuration Checks In the past sound cards have been notorious for interrupt conflict problems with other devices Because these conflicts typically exist between peripher al devices they might not appear during bootup If the sound card operates correctly except when a printing operation is in progress for example an IRQ conflict probably exists between the sound card and the printer port Similar symptoms would be produced for tape backup operations if the tape drive and the sound card were configured to use the same IRQ channel Use a software diagnostic program to check the system for interrupt conflicts Hardware Troubleshooting Techniques 225 Checking the system for resource conflicts in Windows is relatively easy Access Control Panel and double click the System icon From this point click Device Manager and select the Sound Video and Gam
10. be configured differently for docked and undocked situations When the computer is docked and turned on its configuration is reset and the Eject PC option appears on the Start menu However when the computer is not docked the Eject PC option is automatically removed from the Start menu The Windows 2000 and Windows XP Professional operating systems use hardware profiles to determine which drivers to load when the system hard ware changes docked or undocked It uses the Docked Profile to load drivers when the portable computer is docked and the Undocked Profile when the computer starts up without the docking station These hardware profiles are 231 232 Chapter 3 created by the Windows XP operating system when the computer is docked and undocked if the system is PnP compliant If a portable is not PnP compliant you must manually configure the profile by enabling and disabling various devices present when docked and undocked The first check is to verify the power cord connection and docking power supply Next verify that the portable has been properly inserted in the dock ing station or port replicator If a single docking station connection does not work bypass the docking sta tion replicator and try to operate the peripheral directly with the portable unit Check the power supply for both the docking station and the peripher al device and verify that both are turned on Reboot the portable while it is attached to the docking s
11. bootable floppy disk in the new A drive and turn on the system If the system does not boot up to the floppy examine the advanced CMOS setup to check the system s boot order It might be set so that the FDD is never examined during the bootup sequence If the system still does not boot from the floppy check the disk drive cables for proper connection at both ends In many systems the pin 1 designation is difficult to see Reversing the signal cable causes the FDD activity light to stay on continuously The reversed signal cable also erases the Master Boot Record MBR from the disk making it nonbootable Because this is a real possibility you should always use an expendable backup copy of the boot disk for troubleshooting FDD problems If the system has a second floppy disk drive turn it off and exchange the drive s con nection to the signal cable so that it becomes the A drive Try to reboot the system using this other floppy disk drive as the A drive If there is a problem reading or writing to a particular disk try the floppy disk in a different computer to determine whether it works in that machine If not there is most likely a problem with the format of the disk or the files on the disk In the case of writing to the disk you could be dealing with a write protected disk but the system normally informs you of this when you attempt to write to it However if the other computer can read and write to the disk you must t
12. card to be added to the sys tem when it is docked They might also provide multiple PCMCIA slots that add to the existing PC Card capabilities of the portable it is supporting For the most part these connections are simply physical extensions of the ports provided by the portable Therefore if the port works on the portable and doesn t work when connection is made through the docking station gen erally something is wrong with the docking station port replicator However many portable computers employ special keystroke combinations Fn some other key to activate external devices such as a video display monitors or full size keyboards For example some portables detect that the external video display has been attached Others use an Fn key combination to switch the display to the external monitor only and then use another Fn key combination to send the display to both the LCD panel and the external display that is internal external or both If a peripheral device is not working one of the first steps to take is to refer to the portable s documentation to ensure that the external device has been activated For audio problems verify that the speakers are connected to the correct RCA mini jacks not the Line IN or Microphone jacks Check the docu mentation to ensure the sound output has not been muted using an Fn key combination On Windows operating systems the hardware profile information for the portable computer can
13. displays indicating a system configuration and setup failure gt A CMOS Time amp Date Not Set message displays indicating a system configuration and setup failure Typical symptoms associated with system board I O failures include the fol lowing gt The speaker doesn t work during operation The rest of the system works but no sounds are produced through the speaker gt The keyboard does not function after being replaced with a known good unit Configuration Problems Configuration problems typically occur when the system is being set up for the first time or when a new option has been installed The values stored in CMOS must accurately reflect the configuration of the system otherwise an error occurs Incorrectly set CMOS parameters cause the corresponding hardware to fail Therefore check the enabling functions of the advanced CMOS settings as a part of every hardware configuration troubleshooting procedure The many configuration options available in a modern BIOS require the user to have a good deal of knowledge about the particular function being con figured In cases in which you have serious configuration circumstances don t forget that you normally have the option to select default configuration options through the CMOS setup utility Typically if the bootup process reaches the point at which the system s CMOS configuration information is displayed onscreen you can safely assume that no hardw
14. gf Ports COM amp LPT m System devices ool Advanced Power t lll Direct memory ace a cm BMP ee a cel Conflicting device list Properties Refresh Input Output Range 0380 0386 xl B Hard disk controllers Getma based chr sic configuration 0000 F Keyboard E Modem Resource type Setting H Monitors 00040000 OO04FFFF Hi Mouse Memory Range 00060000 OOOBFFFF henge Setting Figure 3 9 Video adapters resources Hardware Troubleshooting Techniques 201 You can also gain access to the Windows video information by double clicking the Display icon found in Control Panel Of particular interest is the Settings tab In Windows 95 the Change Display Type button on this tab provides access to both the adapter type and monitor type settings In Windows 98 and Windows Me the Advanced button on the Settings tab provides access to both the adapter type and monitor type settings through the Adapter and Monitor tabs In Windows 95 the Adapter Type window provides information about the adapter s manufacturer version number and current driver files Clicking the Change button beside this window brings a listing of available drivers from which to select You also can use the Have Disk button with an OEM disk to install video drivers not included in the list You also can alter the manner in which the list displays by enabling the Show Compatible Devices or the Show All Devices options In W
15. gt The attached device is not functional Port Problem Symptoms Typical symptoms associated with serial parallel or game port failures include the following gt A199 432 or 90x IBM compatible error code displays on the monitor printer port gt The printer s Online light is on but no characters are printed when print jobs are sent to the printer gt An 110x IBM compatible error code displays on the monitor serial port error gt A Device Not Found error message displays or you have an unreliable connection gt The input device does not work on the game port Basic Port Checks With newer Pentium systems you must check the advanced CMOS setup to determine whether the port in question has been enabled and if so whether it has been configured correctly Check the PC board that contains the I O port circuitry and its user guide for configuration information This normally involves LPT COM and IRQ settings Occasionally you 214 Chapter 3 must set up hexadecimal addressing for the port addresses however this is becoming rare as PnP systems improve For example a modern parallel port must be enabled and set to the proper protocol type to operate advanced peripherals For typical printer operations the setting can normally be set to Standard Parallel Port SPP mode However devices that use the port in a bidirec tional manner need to be set to Enhanced Parallel Port EPP or Enhanced Capabilities
16. is on This situation might indicate that the microprocessor has been without adequate ventila tion and has overheated When this happens you must replace the fan unit and the microprocessor Verify that the new fan works correctly otherwise a second microprocessor will be damaged Microprocessor Cooling Systems Microprocessor based equipment is designed to provide certain performance levels under specified environmental conditions such as operating tempera ture Using Pentium class microprocessors PC systems are designed to maintain the operating temperature of the device in the range of 30 to 40 degrees C The ideal operating temperature setting varies between microprocessor types and manufacturers Also the location of the CMOS configuration set ting varies between different BIOS makers and versions Some CMOS setup utilities provide a separate Hardware Health configuration screen whereas others integrate it into the Power Management screen Many systems include an additional fan control circuit for use with an optional chassis case fan In these cases the system board features additional BERG con nectors for the chassis temperature sensor and fan control cable If temperature related problems like those described in the preceding sec tion occur you should access the CMOS Hardware Health configuration screen similar to the one depicted in Figure 3 7 and check the fan speed and processor temperature readings 191 192 Chap
17. real damage It might have simply lost track of where it was and now it cannot find its starting point In this case the most attractive option is to reformat the hard disk This action gives the hard drive a new starting point from which to work Unfortunately it also destroys anything that you had stored on the disk If the reformatting procedure is not successful or the system still doesn t boot from the hard drive replace the hard disk drive unit with a working one Troubleshooting CD ROM Drives The troubleshooting steps for CD ROM and DVD drives are nearly identi cal to those of an HDD system The connections and data paths are very similar Basically three levels of troubleshooting apply to CD ROM prob lems These are the configuration level the operating system level and the hardware level Basic Checks In most systems the CD ROM and DVD drives share a controller or host adapter with the hard disk drive Therefore verify their Master Slave jumper settings to ensure they are set correctly Normally the CD ROM or DVD drive should be set up as the master on the secondary IDE channel In this manner each drive has its own communications channel and does not need to share If three or four IDE devices are installed in the system you must determine which devices can share the channels most effectively Windows Checks In the Windows operating systems you can access the contents of the CD ROM or DVD through the CD icon i
18. safe mode the problem exists with the driver you are trying to use with it It might be corrupt or it could be having a conflict with some other driver To check the driver consult Device Manager If Device Manager shows a conflict with the mouse remove the driver and allow the system s PnP process to reinstall it If the correct driver for the installed mouse is not available you must install one from the manufacturer This typically involves placing the manufactur er s driver disk or disc in the appropriate drive and loading the driver using the Update Driver requires disk from original equipment manufacturer OEM option on the Device Manager Mouse Properties page If the OEM driver fails to operate the mouse in Windows you should contact the mouse manufacturer for an updated Windows driver 198 Chapter 3 Troubleshooting Video Figure 3 8 depicts the components associated with the video display As the figure indicates in the case of hardware problems the components involved include the video adapter card the monitor and to a lesser degree the sys tem board Monitor Monitor Video Cable Figure 3 8 Video related components Common symptoms associated with display problems include the following gt There is no display gt The wrong characters are displayed onscreen gt Diagonal lines appear onscreen no horizontal control gt The display scrolls no vertical control g
19. PS 2 mouse port and let the system autodetect it and install the basic Windows mouse drivers However specialty mice including USB connected mice wireless mice and infrared mice along with other pointing devices might require special drivers that are supplied by the manufacturer and loaded from the disk or disc that accompanies the device Older serial mice used one of the PC s seri al ports as their interface These ports had to be properly configured for the serial mouse to work properly When a trackball mouse is moved across the table the trackball picks up dirt or lint which can hinder the movement of the trackball typically evident by the cursor periodically freezing and jumping onscreen On most mice you can remove the trackball from the mouse by a latching mechanism on its bot tom Twisting the latch counterclockwise enables you to remove the track ball Then you can clean dirt out of the mouse The other mechanical part of the mouse is its buttons These items can wear out under normal use When they do the mouse should simply be replaced However before doing so check the Properties of the mouse in the operat ing system to ensure that the button functions have not been altered It would be a shame to throw away a perfectly good mouse because it had been set up for left hand use in the operating system Hardware Troubleshooting Techniques 197 Mouse Hardware Checks The hardware check for the mouse involves isolati
20. T Command Result Codes RESULT CODE DESCRIPTION 0 OK The OK code is returned by the modern to acknowledge execution of a command line 1 CONNECT The modem sends this result code when line speed is 300 bps 2 RING The modem sends this result code when incoming ringing is tiered on the line 3 NO CARRIER The carrier is not detected within the time limit or the carrier is lost 4 ERROR The modem could not process the commana line entry error 5 CONNECT 1200 The modem detected a carrier at 1200 bps 6 O DIAL TONE The modem could not detect a dial tone when dialing 7 The modem detected a busy signal 8 NO ANSWER The modem never detected silence command only g CONNECT 0600 The modem sends this result code when line speed is 7200 bps 10 CONNECT 2400 The modem detected a camier at 2400 bps 4a CONNECT 4800 Connection is established at 4800 pes 12 CONNECT 9600 Connection is established at 9600 bl 13 CONNECT 7200 The modem sends this result code when the line speed is 7200 bps 14 CONNECT 12000 Connection is established at 12000 bps 15 CONNECT 14400 Connection is established at 14400 bps 17 CONNECT 38400 Connection is established at 38400 ee 18 CONNECT 57600 Connection is established at 57600 by pe 22 CONNECT 75TX 1200RX The modem sends this result code when establishing aV 23 anande 23 CONNECT 1200TX 75RX The modem sends this result code when establishing a Y 23 al DELAYED The modem returns this result code when a call fails to Sorte
21. an aH or AS switch that is DIR C AH Or DIR c AS to look in the root directory for the system files and the commann com file It is common to receive a Disk Boot Failure message onscreen if this type of situation occurs 206 Chapter 3 In Windows 9x and Windows Me systems if the clean boot disk has a copy of the FDISK program on it attempt to restore the drive s MBR including its partition information by typing the following A gt FDISK MBR Providing that the hard disk can be accessed with the pir command type and enter the following command at the DOS prompt with the clean boot disk still in the A drive SYS C This command copies the 10 sys mspos sys and commAND com system files from the boot disk to the hard disk drive Turn off the system remove the boot disk from the A drive and try to reboot the system from the hard drive If the system cannot see the drive after booting from the floppy disk an Invalid Drive message or an Invalid Drive Specification message should be returned in response to any attempt to access the drive In Windows 9x sys tems use the FDISK utility to partition the drive Next use the Format sS command to make the disk bootable Any data that was on the drive is lost in the formatting process but it was already gone because the system could not see the drive The process for checking the hard drive on a Windows NT Windows 2000 or Windows XP computer is similar to the one for checki
22. are configuration conflicts exist between the system s basic components After this point in the bootup process the system begins loading drivers for optional devices and additional memory If errors occur after the CMOS screen has been displayed and before the bootup tone you must clean boot the system and single step through the remainder of the bootup sequence to locate the cause of the failure These Hardware Troubleshooting Techniques techniques are described in detail in Chapter 4 Operating System Troubleshooting Microprocessors In the event of a microprocessor failure the system might issue a slow single beep from the speaker along with no display or other I O operation This indicates that an internal error has disabled a portion of the processor s inter nal circuitry usually the internal cache Internal problems can also allow the microprocessor to begin processing but then fail as it attempts additional operations Such a problem results in the system continuously counting RAM during the bootup process It might also lock up while counting RAM In either case the only way to remedy the problem is to replace the micro processor If the system consistently locks up after being on for a few minutes this is a good indication that the microprocessor s fan is not running or that some other heat buildup problem is occurring You also should check the micro processor if its fan has not been running but the power
23. ata communication cabling are available These Hardware Troubleshooting Techniques devices range from inexpensive continuity testers to moderately priced data cabling testers to somewhat expensive time domain reflectometers TDR Although inexpensive continuity testers can be used to check for broken cables data cabling testers are designed to perform a number of different types of tests on twisted pair and coaxial cables These wiring testers nor mally consist of two units a master test unit and a separate load unit as illus trated in Figure 3 4 The master unit is attached to one end of the cable and the load unit is attached to the other The master unit sends patterns of test signals through the cable and reads them back from the load unit Many of these testers fea ture both RJ 45 and BNC connectors for testing different types of cabling When testing twisted pair cabling these devices can normally detect such problems as broken wires crossed over wiring shorted connections and improperly paired connections Figure 3 4 Cable tester TDRS are sophisticated testers that can be used to pinpoint the distance to a break in a cable These devices send signals along the cable and wait for them to be reflected The time between sending the signal and receiving it back is converted into a distance measurement The TDR function is normally packaged along with the other cable testing functions just described TDRs used to tes
24. cause the system to lock up and produce hard memory errors ROM A bad or damaged ROM BIOS typically stops the system completely When you encounter a dead system board examine the BIOS chip for physical damage If these devices overheat it is typical for them to crack or blow a large piece out of the top of the IC package Another symptom pointing toward a damaged BIOS involves the bootup sequence automatically moving into the CMOS configuration display but never returning to the bootup sequence In any case you must replace the defective BIOS with a version that matches the chipset used by the system In situations in which new devices for example microprocessors RAM devices hard drives have been added to the system there is always a chance that the original BIOS cannot support them In these situations the system 194 Chapter 3 might or might not function based on which device has been installed and how its presence affects the system To compensate for these possible prob lems always check the websites of the device and the system board manu facturers to obtain the latest BIOS upgrade and support information CMOS Batteries The second condition that causes a configuration problem involves the sys tem board s CMOS backup battery If a system refuses to maintain time and date information the CMOS back up battery or its recharging circuitry is normally faulty After the backup bat tery has been replaced check the con
25. ce the battery can become conditioned to only run for that amount of time To correct battery memory problems you must fully discharge the battery and then recharge it To accomplish this complete the following steps 1 Turn the portable s Power Management feature off by accessing the Power Management icon in the Windows Control Panel N Restart the computer and access the CMOS setup utility during bootup eo Disable the power management functions in the CMOS settings gt Start the portable computer using only the battery and allow it to run until it completely discharges the battery and quits ol Recharge the battery for at least 12 hours o Repeat this process several times watching for consistently increasing operating times Troubleshooting Docking Stations Port Replicators Most docking stations offer an internal power supply that can operate the portable and its peripheral attachments an external parallel port for printers Hardware Troubleshooting Techniques a serial port for serial devices mice and modems USB ports external VGA DVI video and full size keyboard connections and audio connections for external speakers In addition the docking station can host several types of external storage devices including full sized FDD HDD CD ROM DVD drives Docking stations might also include one or two PCI slots that allow full sized desktop adapter cards SCSI or specialized video or LAN
26. ck to determine whether the Print option from the application s File menu is unavailable gray If so check the My Computer Printers window for correct parallel port settings Be certain that the correct printer driver is selected for the printer being used If no printer or the wrong printer type is selected use the Add Printer Wizard to install and set up the desired printer The system s printer configuration information is also available through the Device Manager tab in the System Properties dialog box found by double clicking the System icon in Control Panel Check this location for printer port setting information Also check the definition of the printer by double clicking the Printer icon found in Control Panel The Windows operating systems come with embedded tools called troubleshooters one of which is designed to help solve printing problems To use the Printing Troubleshooter access the Windows Help system through the Start menu and navigate to the Print Troubleshooter or Printing Troubleshooter in Windows XP The troubleshooter asks a series of ques tions about the printing setup After you have answered all of its questions the troubleshooter returns a list of recommendations for fixing the problem If the conclusions of the troubleshooter do not clear up the problem try printing a document to a file This enables you to separate the printing soft ware from the port hardware Continue troubleshooting the
27. ctions work fine but the nonstandard writing part of the drive might not produce satisfactory results Techniques that can be used to minimize buffer underruns include placing the CD ROM or DVD writer on an IDE channel of its own This keeps the drive from competing with other drives for the channel s available bandwidth Also conducting the write operation on the same drive as the Hardware Troubleshooting Techniques 211 read operation and using reduced write speed options in the R W software can minimize data flow problems In addition the R W software for the drive might not be compatible with the operating system version in use or with the controller chip on the drive Likewise the operating system s multimedia enhancement drivers DirectX in Windows operating systems might not be compatible with the controller or the R W application Always consult the operating system s hardware and software compatibility lists before buying and installing a CD RW or DVD RW drive in a system This typically means using a more expensive drive but for now you do seem to get what you pay for when it comes to rewritable drives If the drive has already been purchased check its documentation for sugges tions and check the manufacturer s website for newer R W applications and driver versions You might also be able to locate a flash program for the drive s BIOS to upgrade it so that it provides better support for the write function S
28. dows 2000 you are asked about which operating system to use Use the up and down arrow keys to highlight Windows 2000 Professional or Windows 2000 Server and then press Enter If alert messages appear read each alert and then click the OK button to close it 3 Open Device Manager click the desired USB device and then click the Remove button Your particular USB device might be listed under Universal Serial Bus Controller Other Devices Unknown Devices or a particular device category such as the Modem entry if the device is a USB modem gt Click the Start menu select the Shut Down option select the Restart entry and then click the OK button ol Connect the USB device directly to the USB port on your computer If the system does not autodetect the device you must install the drivers manually You might need drivers from the device manufacturer to per form this installation IEEE 1394 Adapters and Ports Because Pentium based PCs have largely adopted USB as the default high speed bus FireWire buses are implemented by installing an adapter card in the system to furnish the physical connection points Also there is no direct BIOS support for IEEE 1394 buses in the typical PC However IEEE 1394 adapter cards are plug and play compliant and can converse with the Windows operating systems The FireWire devices that attach to the bus connection do not communicate directly with the system they work with the controll
29. e Controller option If the system detects any conflicts it places an exclamation point within a circle on the selected option From Device Manager choose the proper sound card driver from the list and move into its Resource window The page s main window displays all the resources the driver is using for the card The Conflicting Device List win dow provides information about any conflicting resource that the system has detected in conjunction with the sound card If the Windows PnP function is operating properly you should be able to remove the driver from the system reboot the computer and allow the oper ating system to redetect the sound card and assign new resources to it Check to verify that the Multimedia icon is installed in Control Panel and available through the Start Programs Accessories path Start All Programs Accessories Entertainment in Windows XP Also check Device Manager to see that the correct audio driver is installed and that its settings match those called for by the sound card manufacturer If the drivers are missing or wrong add them to the system through the Add Remove Hardware Wizard found in Control Panel If the driver is not installed or is incorrect add the correct driver from the Available Drivers list If the correct driver is not available reinstall it from the card s OEM disk or obtain it from the card s manufacturer Sound Card Hardware Checks These checks include determining tha
30. e DC voltage readings These measurements usually involve checking the DC side of the power supply unit You can make these readings between ground and one of the expansion slot pins or at the system board power supply connector It is also common to check the voltage level across a system board capacitor to verify that the system is receiving power The voltage across most of the capacitors on the system board is 5V DC The DC voltages that can normally be expected in a PC compatible system are 12V 5V 5V and 12V The actual values for these readings might vary by 5 in either direction am It is normal practice to first set the meter to its highest voltage range to be certain CAUTION that the voltage level being measured does not damage the meter ce A Ono The DC voltage function is used to take measurements in live DC circuits It should be connected in parallel with the device being checked This could mean connecting the reference lead black lead to a ground point and the measuring lead red lead to a test point to take a measurement as illustrat ed in Figure 3 3 Red Meter Cables to Lead Power Supply Probe Cables to Power Supply 5V 5V 5V 5 V GND GND P9 FrPEcgaog Black Meter Ground Probe GND GND 12 V 12v 3 3 V 14 1 3 3 V 3 3 V GND GND 5V GND 5V GND PW OK 5 VSB 12V N lt N N Psi
31. e closeness of the portable s components Hardware Troubleshooting Techniques and the small amount of free air space inside their cases also adds to heat related design problems The internal PC boards of the portable computer are designed to fit around the nuances of the portable case and its components rather than to match a standard design with standard spacing and connections Therefore inter changeability of parts with other machines or makers goes by the wayside The only source of most portable computer parts with the exception of PC Cards and disk drive units is the original manufacturer Even the battery case might be proprietary If the battery dies you must hope that the original maker has a supply of that particular model Although adding RAM and options to desktop and tower units is a relative ly easy and straightforward process the same tasks in notebook computers can be difficult In some notebooks you must disassemble the two halves of the case and remove the keyboard to add RAM modules to the system In other portables the hinged display unit must be removed to disassemble the unit Inside the notebook you might find several of the components are hid den behind other units Figure 3 14 demonstrates a relatively simple disas sembly process for a notebook unit Pull up from These Corners Remove the Screws Figure 3 14 Disassembling a notebook computer 227 228 Chapter 3 In t
32. e many tape drives are used in networked and multiuser environ ments another problem occurs when you are not properly logged on or enabled to work with files being backed up or restored In these situations the operating system might not allow the tape drive to access secured files or any files because the correct clearances have not been met Consult the network administrator for proper password and security clearances Troubleshooting Other Removable Storage Systems Troubleshooting nontypical removable storage systems is very similar to troubleshooting an external hard drive or tape drive The system typically consists of an external unit with a plug in power adapter anything with a motor in it typically requires an additional power source These units typi cally connect to the system through one of its standard I O port connections This requires a signal cable that runs between the system and the device Depending on the exact type of storage device being used it might have a removable media cartridge or container A device driver must be installed for the device to work with the system This is typically a function of the system s PnP process The system should detect the external storage and load the driver for it automatically If the system cannot locate the proper driver it prompts you to supply the location where the driver can be found For the most part external storage systems do not need a support application to be ins
33. eads infinite The resistance function also is useful in checking for cables and connectors By removing the cable from the system and connecting a meter lead to each end you can check the cable s continuity conductor by conductor to verify its integrity You also use the resistance function to test the system s speaker To check the speaker simply disconnect the speaker from the system and connect a meter lead to each end If the speaker is good the meter should read near 8 ohms although a smaller speaker might be 4 ohms If the speaker is defective the resistance reading should be 0 for shorts or infinite for opens Only a couple of situations involve using the AC voltage function for check ing microcomputer systems The primary use of this function is to check the commercial power being applied to the power supply unit As with any measurement it is important to select the correct measurement range how ever the lethal voltage levels associated with the power supply call for addi tional caution when making such measurements The second application for the AC voltage function is to measure ripple volt age from the DC output side of the power supply unit This particular oper ation is very rarely performed in field service situations Cable Testers The most frequent hardware related cause of network problems involves bad cabling and connectors Several specialized handheld devices designed for testing the various types of d
34. els can permit radio Hardware Troubleshooting Techniques 193 frequency interference RFI signals to escape from the case and disrupt the operation of other electronic devices such as radio receivers and televisions RAM The system board RAM is a serviceable part of the system board RAM fail ures basically fall into two major categories and create two different types of failures gt Soft memory errors Errors caused by infrequent and random glitches in the operation of applications and the system You can clear these events just by restarting the system gt Hard memory errors Permanent physical failures that generate NMI errors in the system and require that the memory units be checked by substitution Observe the bootup RAM count on the display to verify that it is correct for the amount of physical RAM actually installed in the system If not swap RAM devices around to see whether the count changes Use logical rotation of the RAM devices to locate the defective part The burn in tests in most diagnostic packages can prove helpful in locating borderline RAM modules You can also swap out RAM modules one at a time to isolate defective mod ules When swapping RAM into a system for troubleshooting purposes take care to ensure that the new RAM is of the correct type for the system and that it meets its bus speed rating Also ensure that the replacement RAM is consistent with the installed RAM Mixing RAM types and speeds can
35. ement utility right click a volume that has already been created and then click Format from the shortcut menu gt In Windows Explorer right click the desired drive letter and then click Format from the shortcut menu gt At a command prompt type the command Format along with the appro priate switches ary If you format an existing partition or volume any data residing in the structure is lost The Windows XP Professional operating system protects its system files by pre venting the system and boot partitions from being formatted LER HDD Hardware Checks If you cannot access the hard disk drive and its configuration settings are correct you must troubleshoot the hardware components associated with 207 208 Chapter 3 the hard disk drive These components include the drive its signal cable and the Hard Disk Controller HDC on the system board Check the HDD signal cable for proper connection at both ends Exchange the signal cable for a known good one Check the Master Slave jumper set tings to ensure they are set correctly Determine whether the system is using the Cable Select option This setting enables the system to dynamically assign the master slave arrangements for multiple IDE drives Likewise check the ID configuration settings and terminator installations for SCSI drives Although it might seem logical to replace the hard drive unit at this point it is quite possible that the hard drive might not have any
36. er on the adapter card Therefore after the adapter card has been installed you must troubleshoot it as you would any other adapter card based peripheral The system should detect the new card when it is installed and load the driver for it automati cally If the system cannot locate the proper driver it prompts you to supply the location where the driver can be found Next you should open Device Manager to ensure the device has been rec ognized there and to check for conflicting device driver information for example an exclamation point in a yellow circle Hardware Troubleshooting Techniques 219 If Device Manager cannot see the device after the proper driver has been loaded and the attached device has power the final step is to check the IEEE 1394 cabling and connectors for continuity and good connections Also verify that the correct FireWire cables are being used a four pin device cannot draw power through the FireWire bus If the device employs its own power supply verify that power is being applied to it If the FireWire bus runs particularly slow and you have multiple devices attached to the system you might have a situation in which the slower device in the middle of the chain is slowing everything down Move the slower device such as a Camcorder to the end of the signal chain Troubleshooting Infrared Ports The Infrared Data Association IrDA protocols for infrared communica tions specify communication ranges up to
37. es CMOS System Option Not Set Failure of CMOS battery or CMOS Checksum test CMOS Display Mismatch Failure of display type verification CMOS Memory Size Mismatch System configuration and setup failure Press F1 to Continue Invalid configuration information CMOS Time and Date Not Set Failure of CMOS battery After the beep tone has been produced in the startup sequence the system shifts over to the process of booting up and begins looking for and loading the operating system Errors that occur between the beep and the presenta tion of the operating system s user interface command prompt or GUI gen erally have three possible sources These sources are summarized in the fol lowing list that includes the typical error messages associated with each source gt Hardware failure physical problem with the boot drive gt General Failure Error Reading Drive x 179 180 Chapter 3 gt Corrupted or missing boot files gt Bad or Missing Command Interpreter gt Nonsystem Disk or Disk Error gt Bad File Allocation Table gt Corrupted or missing operating system files Both configuration problems and bootup problems can be caused by a hard ware or operational failure If the configuration settings are correct but these symptoms are present a hardware problem is indicated as the cause of the problem Conversely bootup problems are typically associated with the operating system Hardware Troubleshooti
38. esent in Device Manager right click the USB controller entry and click Properties If any problems exist a message appears in the device status window shown in Figure 3 12 describing any problems and suggesting what action to take SiS 7001 PCI to USB Open Host Controller Propertie 2 xi General Advanced Driver Resources cs SiS 7001 PCI to USB Open Host Controller Device type Universal Serial Bus controllers Manufacturer Silicon Integrated Systems Location PCI bus 0 device 1 function 2 Device status This device is working properly If you are having problems with this device click Troubleshooter to start the troubleshooter Troubleshooter Device usage Use this device enable fed Figure 3 12 The USB Controller Properties dialog box If the BIOS and controller settings appear to be correct the next items to check are the USB port drivers These ports have a separate entry in Device Manager that you can access by clicking the Universal Serial Bus Controllers option right clicking the USB Root Hub entry and then clicking Properties If a USB device does not install itself automatically you might have con flicting drivers loaded for that device and might need to remove them 217 218 Chapter 3 To remove potentially conflicting USB drivers complete the following steps 1 Disconnect any USB devices connected to the system and start the sys tem in safe mode N Under Win
39. following devices Standard 28800 bps Modem Driver More Info Help cea Figure 3 13 The Windows 9x Diagnostics Tab of the Modems Properties dialog box In Windows XP the Diagnostics tab for the modem is available by clicking the Properties button on the Modems tab of the Phone and Modem Options dialog box The Query Modem button on this tab can be used to perform low level tests on the modem 222 Chapter 3 The Hayes AT Command Set The Hayes command set is based on a group of instructions that begin with a pair of attention characters followed by command words Because the attention characters are an integral part of every Hayes command the com mand set is often referred to as the at command set AT commands are entered at the command line using an ATXn format The xn nomenclature identifies the type of command being given x and the partic ular function to be used n Except for the ata ATDn and atzn commands the at sequence can be followed by any number of commands The ata command forces the modem to imme diately pick up the phone line even if it does not ring The pn commands are dialing instructions and the zn commands reset the modem by loading new default initialization information into it After a command has been entered at the command line the modem attempts to execute the command and then returns a result code to the screen Table 3 2 describes the com mand result codes Table 3 2 A
40. for continuity Neither the older five pin DIN nor the six pin PS 2 mini DIN keyboards can be hot swapped Disconnecting or plugging in a keyboard that has this type of fuse while power is on can cause the keyboard to fail If the fuse is present simply replace it with a fuse of the same type and rating If replacing the keyboard does not correct the problem and no configuration or software reason is apparent the next step is to troubleshoot the keyboard 196 Chapter 3 receiver section of the system board On most system boards this ultimate ly involves replacing the system board Troubleshooting Mouse Problems Most problems with mice are related either to its port connection the mouse driver the trackball in a trackball mouse or a trackball unit and the opera tion of the mouse buttons In newer systems the mouse is typically connected to the USB port or the dedicated PS 2 mouse port on the back of the unit In ATX systems the key board and mouse have been given the same six pin mini DIN connector and unfortunately they do not work interchangeably Although plugging the mouse into the keyboard connector should not cause any physical damage it does cause problems with getting the system to work These connections tend to be color coded so you can check to ensure the mouse is connected to the green connector For PnP compatible mice installation and configuration has become a fair ly routine process Connect the mouse to the
41. hen dead system symptoms are encountered but the power supply is good System Board Symptoms Typical symptoms associated with system board hardware failures include the following gt The On Off indicator lights are visible and the display is visible on the monitor screen but there is no disk drive action and no bootup occurs gt The On Off indicator lights are visible and the hard drive spins up but the system appears dead and there is no bootup gt The system locks up during normal operation gt The system produces a beep code with one two three five seven or nine beeps BIOS dependent gt The system produces a beep code of one long and three short beeps BIOS dependent gt The system does not hold the current date and time gt A DMA Error message displays indicating a DMA controller failed page register test gt A CMOS Battery Low message displays indicating failure of the CMOS battery or the CMOS checksum test gt A CMOS Checksum Failure message displays indicating that the CMOS battery is low or a CMOS checksum test failure gt A 201 error code displays indicating a RAM failure gt A Parity Check error message displays indicating a RAM error 190 Chapter 3 Typical symptoms associated with system board CMOS setup failures include the following gt A CMOS Inoperational message displays indicating failure of CMOS shutdown register gt A CMOS Memory Size Mismatch message
42. his example a panel in front of the keyboard can be removed to gain access to the notebook s internal user serviceable components Four screws along the front edge of the unit s lower body must be removed Afterward the LCD panel is opened and the front panel of the notebook s chassis is pulled up and away to expose a portion of the unit s interior Troubleshooting PCMCIA Problems One of the mainstays of portable computer products is the credit card like PCMCIA cards also known as PC Cards The process for troubleshooting PC Cards is nearly identical to troubleshooting other I O adapter cards PCMCIA cards can be plugged into the system at any time and the system should recognize them In most cases Windows 9x Windows Me Windows 2000 and Windows XP have a copy of the necessary driver software for the PCMCIA adapter being installed and will install it automatically when it detects the adapter Most Windows operating system versions display mes sages telling you that they are installing the drivers required However Windows 2000 and Windows XP just install the drivers without a notice In cases in which the operating system does not have the necessary driver software it prompts you for a path to the location where the driver can be loaded when it detects the adapter PCMCIA manufacturers typically supply drivers for various operating systems on a floppy disk or a CD that comes with the adapter To verify that the PC Card device
43. indows 98 and Windows Me the information about the video adapter card is located on the Adapter tab Clicking the Change button on this tab produces a wizard that guides the process for changing the drivers for the card The first option provided by the wizard is to allow Windows to search for the correct driver or for the user to specify a driver from a list of avail able drivers You can also use the Have Disk button to install video drivers from an OEM disk If the video problem disappears when lower settings are selected but reap pears when a higher resolution setting is used refer to the Color Palette box on the Display Properties Settings tab and try the minimum color settings If the problem goes away contact the Microsoft Download Library MSDL service or the adapter card maker for a compatible video driver If the video problem persists reinstall Windows If the video is distorted or rolling try an alternative video driver from the list Some display problems might be caused by incorrectly set front panel display settings The monitor s front panel controls either analog or digital estab lish parameters for brightness contrast screen size and position and focus Typical problems associated with these controls include fuzzy characters poor or missing colors and incomplete displays Actually there can be several causes of fuzzy characters on the display The first step in checking out this problem is to reset the disp
44. is working access Device Manager If there is a problem with the PC Card device it appears in Device Manager If the PCMCIA adapter s icon shows an exclamation mark on a yellow background the card is not functioning properly Turn the system off and reinsert the device in a different PCMCIA slot If the same problem appears three pos sible sources of problems exist the card might be faulty the PC Card con troller in the PC might be faulty or the operating system might not support the device in question If the Windows Device Manager displays the PCMCIA socket but no name for the card the card insertion has been recognized but the socket could not read the device s configuration information from the card This indicates a problem with the PCMCIA socket installation To correct this problem remove the PCMCIA socket listing from Device Manager reboot the com puter and allow the Windows PnP process to detect the socket and install the appropriate driver for it If the names of the PCMCIA cards do not appear after the restart the reinstallation process was not successful Hardware Troubleshooting Techniques Therefore the PCMCIA socket you are using is not supported by the oper ating system version If the names of other PCMCIA cards do appear in the Device Manager but the card in question does not it is likely that the card has been damaged To test the PC Card device insert a different PC Card device of any type in the slo
45. ist in the system s basic components After this point in the bootup process the system begins load ing drivers for optional devices and additional memory If the error occurs after the CMOS screen displays and before the bootup tone you must clean boot the system and single step through the remainder of the bootup sequence You can still group errors that occur before the beep into two distinct cate gories gt Configuration errors gt Hardware failures A special category of problems tends to occur when a new hardware option is added to the system or when the system is used for the very first time These problems are called configuration problems or setup problems These problems result from mismatches between the system s programmed config uration held in CMOS memory and the actual equipment installed in the system It is usually necessary to access the system s CMOS setup utility in the fol lowing three situations gt When the system is first constructed gt When it becomes necessary to replace the CMOS backup battery on the system board gt When a new or different option is added to the system such as memory devices hard drives floppy drives or video display it might be neces sary to access the setup utility to accept the changes that have been implemented In most systems the BIOS and operating system use plug and play tech niques to detect new hardware that has been installed in the system The
46. ject a problem into the troubleshooting process If there is a printer switch box between the computer and the printer remove the print sharing equipment connect the computer directly to the printer and try to print directly to the device Basic Serial Ports As with parallel ports diagnostic packages typically ask you to place a serial loopback test plug in the serial port connector to run tests on the port Use the diagnostic program to determine whether any IRQ or addressing con flicts exist between the serial port and other installed options The serial Hardware Troubleshooting Techniques loopback plug is physically wired differently from a parallel loopback plug so that it can simulate the operation of a serial device You can also attach a live serial device to the port for testing purposes but like the printer this elevates the possibility that the port might inject other problems into the troubleshooting process Windows Printer Checks You can reach the I O port functions in Windows 9x Windows Me and Windows 2000 through two avenues You can access port information through the Start menu Start Settings You also can reach this information through the My Computer icon on the desktop Printer port information can be viewed through the Printers icon serial port information is accessed through Device Manager In Windows XP the Printers and Faxes folder is located directly on the Start menu Windows Parallel Ports Che
47. lay resolution to standard VGA values If the fuzzy characters remain check the intensity and contrast controls to see if they are out of adjustment Finally you might need to remove built up electromagnetic fields from the screen through a process called degaussing This can be done using a 202 Chapter 3 commercial degaussing coil However newer monitors have built in degaussing circuits that can be engaged through their front panel controls These monitors normally perform a degauss operation each time they are turned on however sometimes the user might need to perform this opera tion The front panel controls can also be used to adjust the Red Green Blue color mixture for the display If the monitor is showing poor colors or only one color examine the color settings using the front panel controls If these settings are responsive to change the problem exists in either the video adapter or the signal cable broken or bad pin or conductor or the monitor s color circuitry is deteriorating XAN You should never remove the outer shell from a CRT video monitor unless you are 7 Fy trained to work inside the case and it is part of your job There are very lethal volt ALERT age levels in excess of 25 000 volts inside the monitor that can remain stored there Lor ser for some time Even if the monitor has been unplugged for some time it can still kill or severely injure you Troubleshooting Floppy Disk Drives Typical s
48. licts Every COM port on a PC requires an IRQ line to signal the processor for attention In most PC systems two COM ports share the same IRQ line The IRQ4 line works for COM1 and COM3 and the IRQ3 line works for Hardware Troubleshooting Techniques 221 COM2 and COM4 This is common in PC compatibles The technician must ensure that two devices are not set up to use the same IRQ channel If more than one device is connected to the same IRQ line a conflict occurs because it is not likely that the interrupt handler software can service both devices Therefore the first step to take when installing a modem is to check the system to determine how its interrupts and COM ports are allocated To install a non PnP device on a specific COM port for example COM2 you must first disable that port in the system s CMOS settings to avoid a device conflict If not the system might try to allocate that resource to some other device because it has no way of knowing that the non PnP device requires it Windows Modem Checks In Windows 9x you can find the modem configuration information by nav igating to Control Panel Modems The Modems Properties dialog box has two tabs the General tab and the Diagnostics tab The Diagnostics tab shown in Figure 3 13 provides access to the modem s driver and additional information Modems Properties L271 x General Diagnostics Windows detected the following ports and has already installed the
49. ly garbled The command interrupts any activity the modem is engaged in and brings it to command mode Modem Hardware Checks Modems have the capability to perform three different kinds of self diag nostic tests gt The local digital loopback test gt The local analog loopback test gt The remote digital loopback test If transmission errors occur frequently you should use the various loopback tests to locate the source of the problem Begin by running the remote digital 223 224 Chapter 3 loopback test If the test runs successfully the problem is likely to be located in the remote computer If the test fails run the local digital loopback test with self tests If the test results are positive the problem might be located in the local computer On the other hand you should run the local analog loopback test if the local dig ital test fails If the local analog test fails the problem is located in the local modem If the local analog test is successful and problems are occurring you should run the local analog test on the remote computer The outcome of this test should pinpoint the problem to the remote computer or the remote modem If the modem is an internal unit you can test its hardware by exchanging it with a known good unit If the telephone line operates correctly with a nor mal handset only the modem its configuration or the communications soft ware can be causes of problems If the modem s software
50. mercial outlet In addition check the monitor s intensity and contrast controls to ensure that they are not turned down Determine which of the video related components is involved On some monitors you can do this by just removing the video signal cable from the adapter card If a raster appears onscreen with the signal cable removed the problem is probably a system problem and the monitor is good If the mon itor is an EPA certified Energy Star compliant monitor this test might not work Monitors that possess this power saving feature revert to a low power mode when they do not receive a signal change for a given period of time Exchange the monitor for a known good one of the same type that is VGA for VGA If there is still a video problem exchange the video controller card with a known good one of the same type Other symptoms that point to the video adapter card include a shaky video display and a high pitched squeal from the monitor or system unit If the sys tem still does not perform properly the source of the problem might be in the system board If you can read the contents of the display through the startup process but then cannot see it after the system boots up you have an operating 199 200 Chapter 3 system related video problem If the Windows video problem prevents you from working with the display restart the system press the F8 function key when the Starting Windows message appears and select the
51. n the My Computer applet The Hardware Troubleshooting Techniques 209 CD ROM drive s information is contained in the System Properties dialog box found by double clicking the System icon in Control Panel The Properties of the installed CD ROM drive are located on the Settings tab Figure 3 11 shows a typical set of CD ROM specifications in Windows 9x Use this device enable Figure 3 11 CD ROM specifications in Device Manager If the correct drivers are not installed load them or contact the CD ROM manufacturer for the correct Windows driver Check the system for old AUTOEXEC BAT and conriG sys files that could contain commands concerning older CD ROM drives These commands overrule the Windows CD ROM configurations and can create problems Make a copy of the file for backup purposes and remove the MSCDEX lines from the original file CD ROM DVD Hardware Checks In many systems the CD ROM and DVD drives share a controller or host adapter with the hard disk drive Therefore if the hard drive is working and the CD ROM drive is not the likelihood that the problem is in the CD ROM or DVD drive unit is very high 210 Chapter 3 Before entering the system unit check for simple user problems gt Is there a CD or DVD in the drive gt Is the label side of the disk facing upward gt Is the disk a CD ROM or some other type of CD If the drive is inoperable and a CD or DVD is locked inside you should inse
52. ng Tools The level of troubleshooting most often performed on PC hardware is exchanging Field Replaceable Units FRUs Due to the relative low cost of computer components it is normally not practical to troubleshoot failed components to the IC level The cost of using a technician to diagnose the problem further and repair it can quickly exceed the cost of the new replace ment unit However a few hardware diagnostic tools can be very helpful in isolating defective hardware components These tools include gt Software diagnostic disk gt Multimeter gt Cable tester gt POST card Software Diagnostic Packages Several commercially available disk based diagnostic routines can check the system by running predetermined tests on different areas of its hardware The diagnostic package evaluates the response from each test and attempts to produce a status report for all of the system s major components Like the computer s self tests these packages produce visual and beep coded error messages Figure 3 1 depicts the Main menu of a typical self booting soft ware diagnostic package Hardware Troubleshooting Techniques 181 PC CHECK VS 03 c Eurosoft UK Ltd 1988 2002 System Information Menu Advanced Diagnostic Tests Immediate Burn in Testing Deferred Burn in Testing SCSI Utilities Show Results Summary Print Results Report About PC CHECK Exit Save Use t to Move Bar lt ENTER gt to Select
53. ng a Windows 9x based system In Windows NT and Windows 2000 the partitioning process is performed through the Disk Administrator and Disk Management utilities respectively These utilities perform all of the basic functions that the FDISK utility does For instance both utilities can be used to partition drives and both show you the basic layout of the system s disks These disk utilities can also provide advanced functions associated with enterprise large scale business oriented computing systems The Disk Administrator and Disk Management utilities can be used to create both tra ditional primary and extended partitions for MS DOS Windows 9x systems or for Windows NT and Windows 2000 systems They can also be used to create volumes partitions that involve space on multiple physical drives The Windows 2000 and Windows XP Disk Management snap in depicted in Figure 3 10 is located under the Computer Management console To access the Disk Management snap in click Start Settings Control Panel Administrative Tools Double click the Computer Management icon and then click the Disk Management entry Because working with volumes is a major administrative task you must be logged on as an administrator or as a member of a Windows 2000 Administrators group to carry out this procedure Hardware Troubleshooting Techniques i Action view lt gt am e g Tree Volume Layout Type File System Status Capacity Free Space
54. ng it from its host port Simply replace the mouse to test its electronics If the replacement mouse works the original mouse is probably defective If its electronics are not working properly few options are available for actually servicing a mouse It might need a cleaning or a new trackball However the low cost of a typical mouse generally makes it a throwaway item if simple cleaning does not fix it If the new mouse does not work either chances are good that the mouse s electronics are working properly In this case the mouse driver or the port hardware must be the cause of the problem If the driver is correct for the mouse the port hardware and CMOS configuration must be checked The system board typically contains all of the port hardware electronics and support so it must be replaced to restore the port mouse operation at that port However if the system board mouse port is defective another option is to install a mouse that uses a different type of port for example use a USB mouse to replace the PS 2 mouse Mouse Configuration Checks When a mouse does not work in a Windows system restart it and move into safe mode by pressing the F5 function key while the Starting Windows message is displayed This starts the operating system with the most basic mouse driver available If the mouse does not operate in safe mode you must check the mouse hardware and the port to which the mouse is connected If the mouse works in
55. ngs option to see the setup for the ports Most seri al printers use settings of 9600 Baud No Parity 8 Bits 1 Stop Bit and Hardware Handshaking Xon Xoff N Click the Resources button to determine the IRQ setup for the port oo Check the user s manual to document the correct settings for the device using the port in question USB Port Checks Because nearly any type of peripheral device can be added to the PC through a USB port the range of symptoms associated with a USB device can include all the symptoms listed for peripheral devices in this chapter Therefore problems associated with USB ports can be addressed in three general areas gt The USB hardware device gt The USB controller gt The USB drivers Hardware Troubleshooting Techniques As with other port types begin troubleshooting USB port problems by checking the CMOS setup screens to ensure that the USB function is enabled there If it is enabled in CMOS check in Device Manager to verify that the USB controller appears there In Windows 2000 the USB con troller should be listed under the Universal Serial Bus Controllers entry or in the Human Interface Devices entry using the default Devices by Type setting If the USB controller does not appear in Device Manager or a yellow warn ing icon appears next to the controller the system s BIOS might be outdat ed Contact the BIOS manufacturer for an updated copy of the BIOS If the controller is pr
56. nnection Most network adapter cards come from the manufacturer with an OEM disk or CD ROM of drivers and diagnostic utilities for that particular card You can run these diagnostic utilities to verify that the LAN hardware is func tioning properly However it might be easier to run the Windows Pine utility from the com mand prompt and attempt to connect to the network In a LAN environ ment you need to know the IP address or the name of a remote computer in the network to which you can direct the PING Both pine and TrAceRT can be used to identify the IP address of a known network address Extensive additional information about PING TRACERT and the other TCP IP utilities ALE and there usage is provided in Chapter 5 Important Resources Check the activity of the light on the back plate of the LAN card if avail able to determine whether the network is recognizing the network adapter card If the lights are active the connection is alive If not check the adapter in another node Check the LAN cabling to ensure it is the correct type and that the connector is properly attached A LAN cable tester is an excellent device to have in this situation Working on Portable Systems One of the biggest problems for portable computers is heat buildup inside the case Because conventional power supplies and their fans are not included in portable units separate fans must be designed in portables to carry the heat out of the unit Th
57. ome CD ROM and DVD R W applications are simply incompatible with different drive BIOS extension versions or DirectX versions Check all of the parties involved to find a collection of components that are all compatible with each other Troubleshooting Tape Drives The basic components associated with the tape drive include the tape drive the signal cable the power connection the controller and the tape drive s operating software The tape itself can be a source of several problems Common points to check with the tape include the following gt Is the tape formatted correctly for use with the drive in question gt Is the tape inserted securely in the drive gt Is the tape write protected gt Is the tape broken or off the reel in the cartridge If any jumpers or switches are present on the controller verify that they are set correctly for the installation Also run a diagnostic program to check for resource conflicts that might be preventing the drive from operating such as interrupt request IRQ and base memory addressing 212 Chapter 3 The software provided with most tape drives includes some error messaging capabilities Observe the system and note any tape related error messages it produces Consult the user manual for error message definitions and correc tive suggestions Check for error logs that the software might keep You can view these logs to determine what errors have been occurring in the system Becaus
58. onics IDE drives check the Master Slave jumper setting to ensure it is set properly for the drive s logical position in the system Remember that there can only be one master drive selection on each IDE channel If both drives share an interface and are set to the same selection neither drive should work If you have more than one device attached to a single interface cable be cer tain that they are of the same type for example all are Enhanced Integrated Drive Electronics EIDE devices or all are ATA100 devices Mixing IDE device types creates a situation in which the system cannot provide the dif ferent types of control information each device needs The drives are incom patible and you might not be able to access either device If the drive is a SCSI drive check to see that its ID has been set correctly and that the SCSI chain has been terminated correctly Either of these errors results in the system not being able to see the drive Check the CMOS setup utility to ensure that SCSI support has been enabled along with large SCSI drive support Basic HDD Checks The first task is to determine how extensive the HDD problem is Place a clean boot disk or an emergency start disk in the A drive and try to boot the system Then execute a DIR command to access the C drive If the system can see the contents of the drive the boot files have been lost or corrupted but the architecture of the disk is intact Modify the DIR command with
59. p plied to the system by the power supply 1 Check the external connections of the power supply This is the first step in checking any electrical equipment that shows no signs of life N Confirm that the power supply cord is plugged into a functioning outlet Verify the position of the On Off switch Aa oC Examine the power cord for good connection at the rear of the unit ol Check the setting of the 110 220 switch setting on the outside of the power supply The normal setting for equipment used in the United States is 110 oa Check the power at the commercial receptacle using a voltmeter or by plugging in a lamp or other 110 volt device into the outlet 188 Chapter 3 Before changing any board or connection always turn the system off first In an ATX ST 7 style system you should also disconnect the power cable from the power supply A This is necessary because even with the power switch off some levels of voltages i Lys are still applied to the system board in these units Other Power Supply Problems The absence of the lights and the fan operation indicate that power is not reaching the system and that at least some portion of the power supply is not functional This type of symptom results from the following two likely pos sibilities 1 A portion of the power supply has failed or is being overloaded One or more of the basic voltages supplied by the power supply is missing while the other
60. pe message appears indicating the controller can not find a recognizable track sector pattern on the drive gt A No Boot Record Found a Nonsystem Disk or Disk Error or an Invalid System Disk message appears indicating that the system boot files are not located in the root directory of the drive gt The video display is active but the HDD activity light remains on and no bootup occurs indicating that the HDD s CMOS configuration information is incorrect gt An Out of Disk Space message appears indicating that the amount of space on the disk is insufficient to carry out the desired operation gt A Missing Operating System or a Hard Drive Boot Failure message appears indicating that the disk s MBR is missing or has become cor rupt gt A Current Drive No Longer Valid message appears indicating that the HDD s CMOS configuration information is incorrect or has become corrupt Hardware Troubleshooting Techniques 205 HDD Configuration Checks While booting up the system observe the BIOS s HDD type information displayed on the monitor Note the type of HDD that the BIOS recognizes as being installed in the system Possible error messages associated with HDD configuration problems include the Drive Mismatch Error message and the Invalid Media Type message Check the drive to ensure that it is properly terminated Every drive type requires a termination block somewhere in the interface For Integrated Drive Electr
61. port by checking the printer driver to ensure that it is the correct driver and version number Right click the Printer icon 215 216 Chapter 3 and click Properties from the shortcut menu Click the Details tab to view the driver s name Click the About entry under the Device Options tab to verify the driver s version number Click the printer port in question after double clicking the Printer icon to open the Print Manager screen Check the Print Manager for errors that have occurred and that might be holding up the printing of jobs that follow it If an error is hanging up the print function highlight the offending job and remove it from the print spool by clicking the Delete Document entry on the Document menu Windows 9x and Windows Me Serial Ports Information on the system s serial ports is contained in three areas in Device Manager These are the Resources entry the Driver entry and the Port Settings entry The Resources entry displays port address ranges and IRQ assignments The Driver entry displays the names of the installed device drivers and their locations The Port Settings entry contains speed and char acter frame information for the serial ports The Advanced entry under Port Settings enables you to adjust the transmit and receive buffer speeds for bet ter operation Check the Device Manager window for correct serial port settings Check the correct serial port settings under Windows 9x 1 Click the Port Setti
62. r aie is considered delayed 32 BLACKLISTED Te ae ils this result code when a call fails to connect and is considered acklistes 40 CARRIER 300 The carrier is detected at 300 bps 44 CARRIER 1200 75 The modem sends this result code when V 23 backward channel cartier is detected 45 CARRIER 75 1200 The modern sends this result code when V 23 forward channel carrier is detected 46 CARRIER 1200 The carrier is detected at 1200 bps 47 CARRIER 2400 The carrier is detected at 2400 bps 48 CARRIER 4800 The modem sends this result code when either the high or low channel carrier in V 22bis modem has been detected 49 PAE 7200 The carrier is detected at 7200 bps 50 RRIER 9600 The carrier is detected at 9600 bps 51 CARRIER 12000 The carrier is detected at 12000 bps 52 CARRIER 14400 The carrier is detected at 1 Hno bps 66 COMPRESSION CLASS 5 MNP Class 5 is active CLA 67 COMPRESSION V 42bis COMPRESSION Y husis active V 42bis 69 COMPRESSION NONE No data compression signals NONE 70 PROTOCOL NONE No error correction is enabled 77 PROTOCOL LAPM V 42 LAP M error correction is enabled 80 PROTOCOL ALT MNP Class 4 error correction is enabled Using the AT Command Set At the command line type atz to reset the modem and enter command mode using the Hayes compatible command set You should receive a o or ok response if the command was processed A returned ok code indicates that the modem and the computer are communicating properly
63. red icon on the taskbar The Infrared Monitor not only notifies you when the computer is communicating with an infrared device but it also indicates how well it is communicating 220 Chapter 3 Troubleshooting Modems A section on troubleshooting modems has to be subdivided into two seg ments gt External modems gt Internal modems You should check an internal modem using the same basic sequence as any other I O card First check its hardware and software configuration check the system for conflicts and check for correct drivers Improper software setup is the most common cause of modems not working when they are first installed Inspect any cabling connections to see that they are connected correctly and functioning properly and test the modem s hardware by substitution If an external modem is being checked it must be treated as an external peripheral with the serial port being treated as a separate I O port Modem Symptoms Typical symptoms associated with modem failures include the following gt There is no response from the modem gt The modem does not dial out gt The modem does not connect after a number has been dialed gt The modem does not transmit after making connection with a remote unit gt The modem does not install properly for operation gt Garbled messages are transmitted gt The modem cannot terminate a communication session gt The modem cannot transfer files COM Port Conf
64. rob lems One of the most basic pieces of electronic troubleshooting equipment is the multimeter These test instruments are available in both analog and digital readout form and can be used to directly measure electrical values of voltage V current in milliamperes mA or amperes A and resistance in ohms Therefore these devices are referred to as VOMs volt ohm milliammeters for analog types or DMMs digital multimeters for digital types Figure 3 2 depicts a digital multimeter With a little finesse you can use this device to check diodes transistors capacitors motor windings relays and coils This particular DMM contains facilities built in to the meter to test transistors and diodes These facilities are in addition to its standard func tions of current voltage and resistance measurement however in computer repair work only the voltage and resistance functions are used extensively Measuring Lead Reference Ground Display DC Volts AC Amps Resistance OHMS Amps VQ Jack COM Jack Figure 3 2 A digital multimeter The first step in using the multimeter to perform tests is to select the prop er function For the most part you never need to use the current function of the multimeter when working with computer systems however the voltage and resistance functions can be very valuable tools Hardware Troubleshooting Techniques 183 In computer troubleshooting most of the tests ar
65. roduced by the BIOS routines Simple POST cards come with a set of light emitting diodes LEDs on them that produce coded error signals when a problem is encountered Other cards produce beep codes and seven segment LED readouts of the error code Figure 3 5 depicts a typical XT AT compatible POST card Figure 3 5 A typical POST card Hardware Troubleshooting Techniques 187 Troubleshooting Power Supply Problems Typical symptoms associated with power supply failures include the following gt No indicator lights are visible with no disk drive action and no display on the screen Nothing works and the system is dead gt The On Off indicator lights are visible but there is no disk drive action and no display on the monitor screen The system fan might or might not run gt The system produces a continuous beep tone Checking Dead Systems Special consideration must be taken when a system is inoperable In a total ly inoperable system there are no symptoms to give clues where to begin the isolation process In addition it is impossible to use troubleshooting software or other system aids to help isolate the problem When the system exhibits no signs of life including the absence of lights the best place to start looking for the problem is at the power supply The operation of this unit affects virtually every part of the system Also the absence of any lights working usually indicates that no power is being su
66. roubleshoot the floppy drive hardware Hardware troubleshooting for floppy disk drives primarily involves exchang ing the FDD unit for another one that is working If necessary exchange the signal cable with a known good one The only other option with most PC compatible systems is to exchange the system board with a known good one 204 Chapter 3 Troubleshooting Hard Disk Drives Typical symptoms associated with hard disk drive failures include the following gt The front panel indicator lights are visible and the display is present on the monitor screen but there is no disk drive action and no bootup gt The computer boots up to a system disk in the A drive but not to the hard drive indicating that the system files on the hard disk drive HDD are missing or have become corrupt gt The computer does not boot up when turned on gt An IBM compatible 17xx error code is produced on the display gt No motor sounds are produced by the HDD while the computer is run ning In desktop units the HDD should generally always run when power is applied to the system however this does not apply to all desk tops or portables when advanced power saving features are used gt A HDD Controller Failure message appears indicating a failure to veri fy hard disk setup by system configuration file error gt AC or D Fixed Disk Drive error message appears indicating a hard disk CMOS setup failure gt An Invalid Media Ty
67. rt a straightened paper clip into the tray release access hole that s usual ly located beside the ejection button This releases the spring loaded tray and pops out the disc If no simple reasons for the problem are apparent exchange the CD ROM drive with a known good one of the same type If the new drive does not work check the drive s signal cable for proper connection at both ends Exchange the signal cable for a known good one Writable Drive Problems An additional set of problems comes into play when a write or rewrite func tion is added to the CD ROM or DVD drive These problems are concen trated in three basic areas gt The quality of the drive s controller circuitry gt The makeup and version of the drive s read write application interface software gt Compatibility with the operating system s multimedia support systems The quality of the drive is based on the type of controller IC it has In less expensive drives the BIOS extension on the drive might not support all of the R W functions required to coordinate with the application package or the operating system s drivers Although all newer CD ROM and DVD drives are ATAPI compatible they might not have an effective method of controlling Buffer Underrun errors These errors occur when the system transfers data to the drive faster than the drive can buffer and write it to the disc The ATAPI compatibility of the chipset ensures that the CD ROM and DVD read fun
68. s are still present 2 A key component on the system board has failed preventing it from processing even though the system has power A defective capacitor across the power input of the system board can completely prevent it from operating The DC voltages that can normally be expected in an ATX PC compatible system are 3 3V 12V 5V 5V and 12V The actual values for these readings might vary by 5 in either direction The black wires in the power supply system board connection are the ground reference wires Figure 3 6 illustrates the correct measurement of voltages at this connector Cables to Probe Power Supply 3 3 V MH 3 3 v Boece 12 V 12 2 3 3 V ore GND BH GND connector PS ON 14 4 5 V GND BE GND GND ile 5 v GND M GND 5 v 18 8 PW OK 5 v 19 9 5 VSB 5 v 20 10 12 v ATX System Board Figure 3 6 Measuring system board voltages Hardware Troubleshooting Techniques 189 Troubleshooting the System Board The microprocessor RAM modules ROM BIOS and CMOS battery are typically replaceable units on the system board If enough of the system is running to perform tests on these units you can replace them Problems with key system board components produce symptoms similar to those described for a bad power supply Both the microprocessor and the ROM BIOS can be sources of such problems You should check both by sub stitution w
69. se components work together with the device to allocate system resources for the device In some situations the PnP logic is not able to resolve all the sys Hardware Troubleshooting Techniques tem s resource needs and a configuration error occurs In these cases the user must manually resolve the configuration problem When you are installing new hardware or software options be aware of the possibility of configuration errors occurring If you encounter configuration or setup errors refer to the installation instructions found in the new com ponent s installation user documentation If you cannot confirm a configuration problem you most likely have a defec tive component The most widely used repair method involves substituting known good components for suspected bad components Other alternatives for isolating and correcting a hardware failure that appears before the boot up depend on how much of the system is operable Normally symptoms can be divided into three sections configuration prob lems bootup problems and operational problems The system s configuration settings are normally checked first It is impor tant to observe the system s symptoms to determine in which part of the sys tem s operation the fault occurs The error messages described in Table 3 1 are errors that occur and are reported before the single beep tone is pro duced at the end of the POST routines Table 3 1 Common Configuration Error Cod
70. ssure is removed The stuck key produces an error message when the system detects it how ever it has no way of detecting an open key An unplugged keyboard or one with a bad signal cable also produces a key board error message during startup Ironically this condition might produce a configuration error message that says Press F1 to continue If the keyboard produces odd characters on the display check the Windows keyboard settings in Device Manager Device Manager is located under the System icon found in Control Panel in Windows 9x and Windows Me In Windows 2000 the path is similar Control Panel System Hardware tab However in both Windows 2000 and Windows XP Device Manager is usu ally accessed through the Computer Management console If the keyboard is not installed or is incorrect install the correct keyboard type Also be cer tain that you have the correct language setting specified in the Keyboard Properties dialog box found by double clicking the Keyboard icon in Control Panel Keyboard Hardware Checks If you suspect a keyboard hardware problem isolate the keyboard as the def inite source of the problem a fairly easy task Because the keyboard is exter nal to the system unit detachable and inexpensive simply exchange it with a known good keyboard If the new keyboard works correctly remove the back cover from the faulty keyboard and check for the presence of a fuse in the 5V DC supply and check it
71. t An error code of one long and six short beeps is produced by the system BIOS dependent gt A CMOS Display Mismatch Failure to Verify Display Type error dis plays gt An error code of one long and two short beeps indicates a display adapter problem BIOS dependent Hardware Troubleshooting Techniques gt Characters are fuzzy gt The monitor displays only a single color Video Hardware Checks The video monitor should come on fairly soon after power has been applied to it With newer monitors the monitor is normally only asleep and is awak ened through the video adapter card when power is applied to the system When the system is shut down the monitor s circuitry senses that no signal is present from the video adapter card and slips into a monitoring mode as long as its power switch is left in the On position If the monitor does not wake up early in the system s startup process and present a display you should assume there is some type of hardware prob lem the bootup action and operating system have not been introduced to the system before the single beep tone is produced However video prob lems that occur after the single beep are more likely to be related to operat ing system configuration settings Check the monitor s On Off switch to see that it is in the On position Also check its power cord to see that it is either plugged into the power supply s monitor outlet or into an active 120V AC com
72. t If the other card works it is very likely that the card in question has been damaged Troubleshooting Portable Unique Storage As with other PCMCIA devices PC Card hard drives are self contained Plug them into the PCMCIA slot and the system should detect them they are hot swappable If the system does not detect the card hard drive use the troubleshooting steps described for other PCMCIA devices Troubleshooting Batteries If you turn your portable computer on and nothing happens the first things to check out include the power supply and the battery If the power supply is plugged in the computer should start up when the On Off switch is engaged However if the computer is running on battery power and the sys tem does not start up the battery could be bad or need to be charged Verify that the battery doesn t need a recharge by trying to start the system with the AC power adapter plugged in Check the power indicator in the sys tem display panel If it is on power is being supplied to the portable If the indicator is not on verify that the power cord is securely connected to a live power source Check all the power connections to ensure that the AC adapter jack is securely connected to the AC adapter port If the portable still doesn t start up you must troubleshoot the system board If the system runs from the AC adapter the battery needs to be recharged or replaced Although a dead system is a classic battery power s
73. t fiber optic cables are known as optical time domain reflectome ters OTDRs 185 186 Chapter 3 POST Cards A POST card is a diagnostic device that plugs into the system s expansion slot and tests the operation of the system as it boots up These cards can be as simple as interrupt and direct memory access DMA channel monitors or as complex as full fledged ROM BIOS diagnostic packages that carry out extensive tests on the system POST cards are normally used when the system appears to be dead or when the system cannot read from a floppy or hard drive The firmware tests on the card replace the normal BIOS functions and send the system into a set of tests The value of the card lies in the fact that the tests can be carried out without the system resorting to software diagnostics located on the hard disk or in a floppy drive The POST routines located in most BIOS chips report two types of errors fatal and nonfatal If the POST encounters a fatal error it stops the system The error code posted on the indicator corresponds to the defective opera tion If the POST card encounters a nonfatal error however it notes the error and continues through the initialization routine to activate as many additional system resources as possible When these types of errors are encountered the POST card must be observed carefully because the error code on its indi cator must be coordinated with the timing of the error message or beep code p
74. t the speakers are plugged into the speaker port It is not uncommon for the speakers to be mistakenly plugged into the card s MIC microphone port Likewise if the sound card does not record sound verify that the microphone is installed in the proper jack not the speaker jack and that it is turned on Check the amount of disk space on the drive to ensure that there is enough to hold the file being produced In the case of stereo speaker systems it is possible to place the speakers on the wrong sides This produces a problem when you try to adjust the balance between them Increasing the volume on the right speaker increases the out put of the left speaker The obvious cure for this problem is to physically switch the positions of the speakers 226 Chapter 3 Troubleshooting Network Cards Cabling is one of the biggest problems encountered in a network installation Is it connected Are all the connections good Is the cable type correct Has there been any termination and if so has it been done correctly The most efficient way to test network cable is to use a line tester to check its func tionality With UTP cabling simply unplug the cable from the adapter card and plug it into the tester If coaxial cable is used you must unplug both ends of the cable from the network install a terminating resistor at one end of the cable and plug the other end into the tester The tester performs the tests required to analyze the cable and co
75. tacts of the battery holder for corro sion If the battery fails or if it has been changed the contents of the CMOS con figuration are lost After replacing the battery it is always necessary to access the CMOS setup utility to reconfigure the system Troubleshooting Keyboard Problems Most of the circuitry associated with the computer s keyboard is located on the keyboard itself However the keyboard interface circuitry is located on the system board Therefore the steps required to isolate keyboard problems are usually confined to the keyboard its connecting cable and the system board Keyboard Symptoms Typical symptoms associated with keyboard failures include the following gt No characters appear onscreen when entered from the keyboard gt Some keys work whereas others do not work gt A Keyboard Error Keyboard Test Failure error appears gt A KB Interface Error Keyboard Test Failure error appears gt An error code of six short beeps is produced during bootup BIOS dependent gt The wrong characters are displayed Hardware Troubleshooting Techniques 195 gt An IBM compatible 301 error code appears gt An Unplugged Keyboard error appears gt A key is stuck Basic Keyboard Checks The keys of the keyboard can wear out over time This might result in keys that don t make good contact no character is produced when the key is pressed or that remain in contact stick even when pre
76. talled However you should refer to the device s documentation and follow its installation procedures to determine whether the device can be installed with just a driver Check the power supply at the external unit to ensure power is being applied Most external media devices have power lights to indicate that power is pres ent Next check the removable media if present by exchanging it with anoth er cartridge or tape Next you should open Device Manager to ensure the device has been recognized there as well as to check for conflicting device driver information If Device Manager cannot see the device after the proper driver has been loaded and the storage device has power the final step in checking the system is to check the signal cable by substitution The only other step Hardware Troubleshooting Techniques 213 typically available is to test the entire storage system on another machine in most cases there isn t a second storage system available to use a source of known good parts Troubleshooting Port Problems Failures of the serial parallel and game ports tend to end with poor or no operation of the peripheral Generally there are only four possible causes for a problem with a device connected to an I O port gt The port is defective gt The software is not configured properly for the port that is the resource allocation speed or protocol settings do not match gt The connecting signal cable is bad
77. tation Then check any signal cables between the docking station and the peripheral If the PS 2 mouse connection does not work verify that it has not been installed in the PS 2 keyboard connector by mistake Verify that the mouse port is enabled in the CMOS setup utility Likewise if you are using a USB or serial mouse verify that the port is enabled in CMOS and that it is con nected to the correct port Check the serial port s configuration settings to verify that a proper device driver has been installed for the mouse If the portable s touch pad works but the external mouse does not check the computer s documentation for an Fn key combination requirement for the mouse
78. ter 3 If these readings are outside of the designated range you can enter a differ ent value for the temperature set point If no fan speed measurement is being shown check to see if the fan is actually turning If not you should turn the system off as soon as possible check the operation of the fan and replace it before the microprocessor is damaged 12V Voltage 4 Enter Figure 3 7 The CMOS Hardware Health configuration screen Other alternatives when dealing with thermal problems in a PC include installing an additional chassis fan to help move cooler air through the sys tem unit changing the microprocessor fan for one that runs faster over a given range of temperatures and flashing the BIOS to provide different fan control parameters Check for missing slot covers that can disrupt airflow in the case and route internal signal cables so that they do not block the flow of air through the case Likewise check the case s front cover alignment as well as any upper or side access panels to ensure they are well fitted If the airflow openings in the front cover are blocked the system fans cannot properly circulate air though the case If the front panel or any of the access doors or covers are not in proper posi tion they could create alternate airflow paths that disrupt the designed cool ing capabilities of the system In addition to disrupting the designed airflow capabilities of the case missing or misaligned case pan
79. upply problem you might encounter several other battery related problems with portable computers These include problems that present the following types of symptoms gt You receive warning messages about the battery not charging gt The computer experiences intermittent system shut downs when operat ing with only the battery gt The computer does not recognize its network connection when operat ing with only the battery 229 230 Chapter 3 gt The computer and input devices are slow when operating with only the battery gt The computer loses the time and date information when operating on battery power A loose or improperly installed battery can cause these problems They can also appear when the battery is toward the end of its charge recharge cycle Check the installation and attempt to recharge the battery using the portable computer s AC adapter The actual life of a laptop computer battery varies from just under one hour to over two hours in each sitting If you are experiencing battery life cycles that are significantly shorter than this for example 10 to 15 minutes you might have a problem referred to as battery memory Battery memory is a condition that occurs with some types of batteries in which the battery becomes internally conditioned to run for less time than its designed capacity for example if you routinely operate the computer using the battery for an hour and then plug it back in to an AC sour
80. ymptoms associated with floppy disk drive FDD failures during bootup include the following gt FDD error messages are encountered during the bootup process gt An IBM compatible 6xx such as 601 error code is displayed gt An FDD Controller error message displays indicating a failure to verify the FDD setup by the system configuration file gt The FDD activity light stays on constantly indicating that the FDD sig nal cable is reversed Additional FDD error messages commonly encountered during normal sys tem operation include the following gt Disk Drive Read Write Seek error messages appear gt The No Boot Record Found message appears indicating that the system files in the disk s boot sector are missing or have become corrupt gt The system stops working while reading a disk indicating that the con tents of the disk have become contaminated gt The drive displays the same directory listing for every disk inserted in the drive indicating that the FDD s disk change detector or signal line is not functional Hardware Troubleshooting Techniques 203 A number of things can cause improper floppy disk drive operation or fail ure These items include the use of unformatted disks incorrectly inserted disks damaged disks erased disks loose cables drive failure adapter failure system board failure or a bad or loose power connector Basic FDD Checks If there is a problem booting the system insert the

Hardware Troubleshooting Techniques

Contents

Download Pdf Manuals

Related Search

Related Contents