PDI 895 - PDIMeters
Contents
1. axe AAAH EE 47 Duty Cycle What is it esssssssseem 48 Frequency Hz What is it sse 48 Component Tests Input 1 Temperature Tests u 1 nne 49 2 Thermistor Variable Resistance 2 wire 50 3 Potentiometers Variable Resistance 3 wire 53 4 Oxygen Sensor O2 Tests 56 5 Pressure Sensor Tests sseeeenene 57 Component Tests Output Output Devices icr E DROP OE ied 58 Speclificatlotis uere n cette teen tied ee 59 General Specifications eeeeeeeeeeeeeeeeeee esent 59 Electrical Specifications 2i iret ceo tee croce an aah 60 iii Introduction This chapter covers brief introductory information and safety precautions APO RANGE HOLD 2 XtnP E d o en RPM AC gt N 1000 A 341832 F e Y Introduction Safety N DANGER e Engines produce carbon monoxide which is odorless causes slower reaction time and can lead to serious injury When the engine is operating keep service areas WELL VENTI LATED or attach the vehicle exhaust system to the shop exhaust removal system Set the parking brake and block the wheels before testing or repairing the vehicle It is especially important to block the wheels on front wheel drive vehicles The parking brake does not hold the drive wheel2. Component Tests Input Cont d 5 Pressure sensor Tests The electrical tests for pressure sensors such as the Manifold Absolute Pressure MAP and Barometric Pressure BARO vary greatly depending upon type and manufacturer Consult the vehicle service manual for the schematic specifcations and test procedures Gineral Testing Procedures Note You cannot do a resistance Q test for pressure sinsors Analog Sensor An analog sensor can be tested with the same series of voltage V tests suggested for 3 wire potentiometers In place of sweeping the sensor use a vacuum pump to vary the pressure on the sensor Digital Sensor Set the meter rotary switch to the Hz setting and perform the same series of tests suggested for 3 wire potentiometer voltage tests In place of sweeping the sensor a vacuum pump is generally used to vary the pressure on the sensor In all cases refer to a vehicle service manual for the correct procedure 57 Basic Component Testing Component Tests Output Output Devices The electrical tests for output devices vary greatly depending upon type and manufacturer Consult the vehicle service manual for the schematic specifcations and test procedures Primary output devices actuators are a form of an electromagnet that is either ON or OFF The ON OFF signal in general will be in one of three configurations ON or OFF only switch Check for continuity with the switch in the ON
3. If the reading is not negative discon nect the clamp turn it over and e reconnect Approximate Amperage Draw 4 Cyl 150 180 Amp Maximum 6 8 Oyl under 300 CID 180 210 Amp Maximum 6 8 Cyl under 300 CID 250 Amp Maximum 33 Basic Diagnostic Testing Charging System Tests 1 Battery This test checks for alternator output voltage at the battery DOCE E Set the rotary switch to Voltage Connect the positive lead to the positive battery terminal e Connect the negative lead to the negative battery terminal Make sure all vehicle accessories are turned OFF AUTO POWER OFF Start the engine and hold at m 1500 RPM C F VORPM A reading of 13 1 15 5 volts is an acceptable charging rate If the voltage is low check for Loose cracked or glazed drive belt Loose or faulty wires or connec tors Red Defective alternator or regulator See 2 Alternator voltage Output Loaded 34 Basic Diagnostic Testing Charging System Tests Cont d 2 Alternator Voltage Output Loaded This test checks for alternator output voltage This test is neces sary only if the vehicle failed 1 Barrery test Set the rotary switch to the Voltage setting Connect the positive lead to the battey B output post on the back of the alternator Connect the negative lead to the negative battery term
4. OR Select the X10RPM range with rotary switch 1 000 to 12 000 RPM Multiply the displayed reading times ten to get actual RPM Insert the inductive pick up con necting terminal into the meter Ground lead in COM terminal Output lead in V O RPM terminal Connect the inductive pickup to a spark plug wire If no reading is received unhook the clamp turn it over and connect again Press the RPM button to toggle between RPM for 2 Cycle Distributorless Ignition System DIS or RPM for 4 Cycle engines Note Position the inductive pick up as far away from the distributor and the exhaust manifold as possible Position the inductive pick up to within six inches of the spark plug or move it to another plug wire if no reading or an erratic reading is received ag op Los COM VORPM MAX 16 Getting Started Meter Functions Duty Cycle 96 Select the Duty Cycle range with the rotary switch Insert Black lead in COM terminal Red lead in V Q RPM terminal Connect the Black test probe to the ground Connect the Red test probe to the signal wire circuit The illustration for a mixture control solendoid is shown with the metering rod in the closed position Black Red Mixture Control Shown Meter Functions Dwell Select desired Dwell range with the rotary switch Insert Bl
5. Secondary Ignition Wire Resistance Test 2 This test checks for open circuits or high resistance in the second ary sparkplug wires Important Twist and bend the sparkplug wire while measuring the resistance for this test Set the rotary switch to the Resistance Q Insert Black lead in COM terminal Red lead in V O RPM terminal Connect the test probes to op posite ends of the sparkplug wire Typical measurements are approximately 1 000Q s per inch of wire For example 10 inch cable 10 0000 39 Black Basic Diagnostic Testing Ignition System Tests Cont d 4 Distributor Cap Rotor Resistance Test This test checks for open circuits pi or high resistance in the distribu E tor cap and rotor Set the rotary switch to the Resistance Q Insert Black lead in COM terminal Red lead in V O RPM terminal Dist Cap Center Connector Test Connect the test probes to oppo site ends of the distributor cap terminal see illustration In general resistance Q should be 5K 10K Refet to the Manufacturer s specifications Rotor Test Connect the test probes to oppo site ends of the rotor contacts Black see illustration Black In general resistance should de Red 4 0 1Q or less Refer to the Manufacturer s specifications 40 Basic Diagnostic T
6. allel Positive to the circuit coming from the power source negative to the negative cir cuit from the sensor Turn the ignition switch ON do not start the engine Black Red 4 Measurement should be 5 9 volts check the manufacturer s specifications Basic Component Testing Component Tests Input Cont d Thermistor Variable Resistance 2 wire Tests Con t Voltage Change Connect jumper wires between the connector and the sensor Connect the test probes in par allel Positive to the circuit coming from the power source negative to the negative cir cuit from the sensor Start the engine conn COM VORPII D The voltage should change as the temperature changes This is the signal that is sent to the computer for processing Refer to the manufacturer s specifications If the voltage change is not within specifica tions look for sources of resistance due to poor connec tors connections or breaks in the wiring 52 Basic Component Testing Component Tests Input Cont d 3 Potentiometers Variable Resistance 3 wire Tests The potentiometer is a variable resistors The signal generates is used by the vehicle computer to determine postion and direction of movement of a device within the component PASSAGE Resistance Select the Ohms 2 range with the rotary switch Disconnect the sensor Connect the test
7. engine for 2 3 seconds The example shown has 4 con nectors and 2 wires and 2 solenoid connections A voltage drop of more than 0 8 volts would indi cate a poor circuit Clean and inspect the battery and starter cables solenoid and cable connections test again Note A defective starter solenoid may cause Important Repeat this test when an excessive voltage drop check the the engine is thoroughly warmed cables and connections before repla up Heat expansion of metal cing the solenoid cause resistance to increase 32 Basic Diagnostic Testing Starter Motor Testing 1 Starter Current The Bettery tests and the Voltage Drop tests have verified that there is adequate battery voltage at the starter Next check for excessive starter motor current draw LU Connect a Current Clamp around the negative or positive battery cable e Set the rotary switch to the Voltage setting Note 1mV 1Amp Disable the ignition so the en gine doesn t start crank the AUTO POWER OFF HA mA engine for 2 3 seconds FUSED 40054 COM MAX Note The current clamp measures amps in the direction of electrical flow Make NG sure the arrow on the clamp is pointed Red in the direction of the current flow in the cable o tz Quick Test Turn the ignition and all accessories X 7 OFF Place the clamp on the battery cable then turn the headlights on
8. than you expect the current or voltage to be Then select a lower range if better accuracy is needed If the range is too high the readings are less accurate If the range is too low the meter shows OL over limit Getting Started Push button Functions Alternate Function Button Press the Alternate Function a button to toggle between DC and AC in the voltage and current measurements Press the button to toggle to the resistance audible and diode modes if the rotary switch is Set to 2 em position Range Select The range is automatically i selected by the meter But you can also manually select M a range within a function by ee pressing the RANGE button Range Exit To exit the RANGE mode and return to autoranging press and hold the RANGE button for 2 seconds Note e If the range is too high the readings are less accurate If the range is too low the meter shows OL over limit RN Data Hold The Data Hold Feature stores the last reading in memory Press the Data Hold button once to hold the present reading Press the Data Hold button again to exit and resume readings Getting Started Meter Functions Voltage V gt The meter will automatically select the best voltage V range Press the Alternate Function button to select AC or DC Insert e Black lead in COM terminal e Red lead in V Q RPM termi
9. tion are Radiators Transmission Heaters A C Condensers A C Evaporators Engine Coolant Sensors Coolant Temperature Switches Air Temperature Sensors AUTO POWER OFF HA mA FUSED 4009 COM C F VORPM WELLL mM EN 49 Basic Component Testing Component Tests Input Cont d 2 Thermistor Variable Resistance 2 wire Tests Thermistors are variable resistors that are sensitive to temperature level changes As the temperature changes the thermistor s resistance value changes Select the Ohms 2 range with the rotary switch Connect the test probes to the sensor terminals The Ohms reading should match the temperature of the sensor see manufacturer s specifications AUTO POWER OFF HA mA F VORPM Block Typical thermistor applications are Engine Coolant Temp ECT Air Charge Temp ACT Manifold Air Temp MAT Vane Air Temp VAT Throttle Body Temp TBT 50 Basic ComponentTesting Component Tests Input Cont d Thermistor Variable Resistance 2 wire Tests Con t Voltage Presence Disconnect the vehicle wiring harness at the sensor Select the Voltage range with the rotary switch Insert Black lead in COM terminal Red lead in V O RPM terminal CF fusca COM VOR ps Connect the test probes in par
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11. Getting Started Maintenance Fuse and Battery Replacement A WARNING Avoid electrical shock remove test leads before opening case Do not operate the meter or rotate the meter switch when the case is open 1 To replace a battery or fuse loosen the three screws in the case back and lift off the front case Replace the battery with an 9 Volt battery NEDA 1604 IEC 6F 22 2 If no current measurements are possible check for a blown overload protection fuse Important To prevent contamination of the circuits your hands must be clean and the printed circuit board must be held by the edges Replace the fuses with the same type of fuse 10A is a F10A 500V high energy fast acting fuse uA mA is a F500mA 500V fast acting fuse Make sure the replacement fuse is centered in the fuse holder 3 Re assemble the case then fasten the three screws 20 Getting Started Trouble Shooting 1 Meter will not turn ON Check the battery contacts for a tight fit Check for a minimun battery voltage of 8 0 volts 2 Ampere reading is erratic or there is no reading at all Disassemble the meter back cover and test the fuses for continuity 3 Meter reading is erratic Printed circuit board contaminated from handling with hands Low battery Open circuit in a test lead frayed or broken wire Wrong range selected Blown fuse 4 Meter readings do not change Hold feature
12. and OFF position Duty Cycle Mixture Control Solenoid Measure the percent of high or low time in a duty cycle In most cases the low time is the ON time d Switch EE Low Time One Duy Cycle Mixture Control Solenoid 58 Specifications General Specifications GENERAL SPECIFICATIONS Display 334 digit 4000 counts liquid crystal display LCD with function ahd units sign annunciators Polarity Automatic negative polarity indication Overrange Indication OL mark indication Zero Automatic Low Battery Indication The E3 is displayed when the battery voltage drops below the operating level Measurement Rate 2 times per second nominal Auto Power Off Approx 10 minutes Operating Environment 0 C to 50 C 32 F to 122 F at 7096 R H Storage Environment 20 C to 60 C 4 F to 140 F at 8096 R H Accuracy Stated accuracy at 23 C 5 C 7596 R H Temperature Coefficient 0 1 x specified accuracy C 0 C to 18 C 28 C to 50 C Altitude 6561 7 Feet 2000m Power Single standare 9 Volt battery NEDA 1604 IEC 6F22 Battery Life 150 hours typical with carbon zinc Dimensions 165mm H x 78mm W x 42 5mm D Weight Approx 285g including holster 59 Specifications Electrical Specificatios ELESCTRICAL SPECIFICATIONS e Accuracy is given as of reading number of least significant dig
13. as a percent of the total cycle Frequency Hz What is it Frequency is the number of times a voltage pattern repests positive compared to negative ON com Volts pared to OFF during one 1 sec 0 Volts ond of time For example fre quency Hz measurements are Volts specified for digitally controlled Manifold Absolute Pressure sen sors The frequency of the ON OFF signals per second are mea sured and displayed Frequency Hz is shown as Ana Volts NO a NG E p log A continuous positive to nega 0 Volts tive cycle or Digital A positive to negative ON to off cycle 1Second Analog Signal 1Second Digital Signal 48 Basic Component Testing Component Tests Input 1 Temperature Tests Many components that regulate teamperature can be tested by measuring the surface tempera ture of the area surrounding the component Connect the K type thermocouple to a TEMP adapter Match the polarity of the adapter to the polarity of the thermocouple Connect the TEMP adapter to the VQ and COM jacks Set the rotary switch to the Temperature range you desired to be measured Touch the end of the tempera ture probe directly to the sur face of the component to be tested Compare your readings with the mamufacturers specifications The temperature should be within 10 F 45 C of the data stream values Some of the components that can be tested for temperature varia
14. than 0 1 volt per voltage potential when measured wire ground connection across a circuit or component creating resistance switch or solenoid The resistance decreases the amount of voltage available The bulb will not light or the motor will not turn if the voltage is too low Connection Connection What Should be Tested 0 1V Max 0 1V Max Each wire ground connection switch solenoid and the complete circuit should be tested Each connection point is a potential otal resistance should be no more source of increased resistance than 0 4V Max as the expmple shown 28 Basic Diagnostic Testing Voltage Drop Testing 1 Negative Engine Ground This test checks for engine ground efficiency Set the rotary switch to Voltage Touch the positive lead to the positive battery post and the negative lead to the negative battery post Note the reading this will be the base voltage to compare your test voltage reading against Auro POWER OFF CF VORPM Connect the positive lead to a clean spot on the engine block Connect the negative lead to the negative battery post Disable the ignition so the engine doesn t start crank the engine for 2 3 seconds The example shown has 2 con nectors 1 wire 1 ground and 1 terminal to battery post A volt age drop of more than 0 5 volts would indicate a poor ground cir cuit Impo
15. three basic component groups These groups are 1 Sensors they are input devices that supply information about engine operating conditions and the surrounding environment to the vehicle computer 2 Engine Control Module a vehicle computer that processes the information supplied by the sensors then sends an electronic command to the appropriate component actuators 3 Actuators these are output devices that may be electrical mechanical or vacuum components controlled by the vehicle computer Coolant Oxygen Sensor Sensor Typical Sensors Vacuum Throttle Barometric Sensor Position Sensor Sensor Vehicle Computer Electro Purge Mechanical Carburetor Ignition Exhaust Gas Torque Spark Recirculating Converter Fuel Injection Advance Valve Clutch Typical Actuators 44 Basic Component Testing Computer Controlled Systems Cont d Basic Daignostics for the Computer Controlled Engine There are two important steps that must always be followed when diagnosing and repairing vehicles with computer controls Do basic engine diagnostics first Many problems can be traced to lack of routine maintenance on components such as plug wires filters and spark plugs Also check for vacuum leaks on any vehicle new or old A complete engine diagnosis should precede any electrical system diagnostics Follow the published Diagnostic Charts EXACTLY through every step to make a repair on a computer component 45 Ba
16. COMPREHENSIVE INSTRUCTION MANUAL AUTOMOTIVE MULTIMETER Complete step by step electrical systems troubleshooting guide included DISCLAIMER This manual tells you how to use the meter to perform diagnostic tests and to find possible locations of vehicle problems It does NOT tell you how to correct the problems All information illustrations and specifications contained in this technincal manual are based on the latest information availabte at the time of publication The right is reserved to make changes at any time without notice CE Safety Conforms to IEC61010 1 EN61010 1 CATIII 600V Class II Pollution degree 2 Indoor use CAT III Is for measurements performed in the building installation EMC Conforms to EN61326 The symbols used on this instrument are A Caution refer to accompanying documents O Equipment protected throughout by Double insulation Class IT Alternating current Direct current Ground Introduction About This Manual Chapter Descroption Introduction Table of Contents e Safety Warnings Getting Started e Meter Basics e Meter Functions e Maintenance Basic Diagnostic Testing e Battery Testing Voltage Drop Testing e Starter Motor Testing Charging System Testing e Ignition System Testing Basic Component Testing Computer Controlled Systems Component Tests Input Component Tests Output Specifications General Specificat
17. PORTANT Turn the power OFF on the test circuit gt Select the Audible Continuity em range with the rotary switch Press the Alternate Function button to select Audible Continuity Insert Black lead in COM terminal Red lead in V Q RPM terminal Connect one test probe to each end of the circuit to be tested Circuit complete the meter will beep Circuit open there is no beep 9 and the display shows OL over limit 12 HA mA Black Circuit open no beep Circuit complete beep sounds Getting Started Meter Functions Diode Check gt IMPORTANT Turn the power OFF cm CER on the test circuit gt Select the Diode Check Pt setting with the rotary switch Press sthe Alternate Function button to select Diode check Insert Black lead in COM terminal Red lead in V Q RPM terminal Touch the Black test probe to the negative side of the diode Touch the Red test probe to the positive 4 side of the diode Reverse the probes Black to the positive side of Red to the negative side N ote A good diode will read low in one direction and high in the other direction when the probes are reversed A defective diode will have the same reading in both directions or read between 1 0 to 3 0V or OL over Black Red limited in both directions Reverse probes Di
18. ack lead in COM terminal Red lead in V O RPM terminal Connect the Black test probe to ground Connect the Red test probe to the wire that connects to the breaker points see illustration Getting Started HA mA Black 18 AUTO POWER OFF FUSED aoma COM MAX Domi DIAG a F VORPM To Breaker points Getting Started Meter Functions AC or DC Current A IMPORTANT All current measured flows through the meter It is important that you do not Measure current greater than 500 Volts AC or DOC with respect to ground Exceed 60 seconds when measuring continuous current between 1A 10A Allow five minutes for cool down before continuing Select the 10A mA or uA range with the rotary switch Press the Alternate Function button to select AC or DC Insert Black lead in COM terminal Red lead in the 10A oruA mA terminal select 10A if you are unsure of the current draw IMPORTANT Turn OFF all power to the circuit or disconnect the circuit from the power source Connect The Red probe to the side of the circuit closest to the power source The Black probe to the side of the circuit to ground Turn the power ON and test Black Power Source arun Side Note Current must always be measured with the meter test probes connected in series as described 19
19. and the 10A terminals are protected by fuses To avoid possible injury or damage use only in circuits limited to 400mA to 10A for 60 seconds See also Fuse Replacement Introduction Safety Cont d IMPORTANT To maintain accuracy of the meter replace the discharged battery immediately when the battery symbol appears on the meter display Avoid measuring error from outside interference keep the meter away from spark plud or coil wires Avoid damaging the meter when testing voltage Disconnect the test leads from the test points before changing functions Do not exceed the limits shown in the table below input imi ACVolts Volts V G RPM 600VAC rms CCT Volts 600VDC 1 Ohm resistance V O RPM 500V AC DC Diode CEO UA mA 400mA AC DC AC DC 10A 10A AC DC RPM sd Duty a 96 V Q RPM 500V AC DC Dwell Dwell ange X 10Amp measurement for 60 seconds maximum 1 Ohms can not be measured if voltage is present ohms can be measured only in a non powered circuit However the meter is protected to 500 volts Getting Started This chapter will help yor get started It describes the basic functions of the Meter APO RANGE HOLD 2 xtonP E d gt en RPM nA vt AG AUTO POWER OFF HA mA Op 0 EN FUSED CF 400m COM VORPM MAX Getting Started Metetr Basics 1 Digital display Display features e a Four character
20. digital display pa b Symbols to identify function The digital display is best forstable input 2 Function buttons Press the button to select a function A symbol will display to verify your choice Aton ita doo P anne T 3 Rotary Selector Switch Turn this switch to select a function or turn the meter OFF 4 Test Lead Terminals The Black test lead is used in the Common COM terminal for all tests The Red test lead is used to measure Amps or Volts Getting Started Meter Basics Cont d Digital dispaly When DWELL of cylinders is selected with the rotary switch Press RANGE buton to manually select a range Diode test Continuity test ARMEN A xy DS E em h RPM C F Low Battery Replace the meter battery when this symbol displays Negative Polarity Indicator Units of measure dwell degrees duty percent milli m 1 1 000 volts V Auto power off mega M 1 000 000 kilo k 1 000 ohms Q Hertz Hz Press Alt Function button to select Alternating Current AC or Direct Current DC Getting Started Meter Basics Cont d Function and Range Select Turn the rotary swich in either direction to select a function The Range is automatically selected by the meter But you can also select a range within a function by pressing the range button Always select a range higher
21. er to Starter Solenoid This test checks battery source efficiency to the starter solenoid Set the rotary switch to Voltage Establish the base voltage that you will compare test voltage against see base voltage Volt Drop Test 1 Connect the positive lead to the positive battey terminal Connect the negative lead to the positive terminal on the starter soleniod Disable the ignition so the en gine doesn t start crank the engine for 2 3 seconds The example shown has 2 con nectors and 1 wire A voltage drop of more than 0 3 volts would indicate a poor circuit Clean and inspect the battery cables and cable connections test again 31 Starter Solenoid Important Repeat this test when the engine is thoroughly warmed up Heat expansion of metal cause resistance to increase Basic Diagnostic Testing Voltage Drop Testing Cont d 4 Battery Power to Complete Starter Circuit This test checks battery power efficiency to the starter through the starter solenoid Set the rotary switch to Voltage Establish the base voltage that you will compare test voltage against see base voltage Volt Drop Test 1 Connect the positive 4 lead to the 4 battery terminal Connect the negative lead to the positive terminal on the starter motor Disable the ignition so the en gine doesn t start crank the
22. ery Turn the ignition key ON Touch the Red test probe to the three test point shown Ground reading should be the same voltage as the ground Computer or battery Supply line reading should be the same voltage as the input source Computer or battery Signal Line reading should be 0 or the same voltage as the input source Computer or battery The reading will toggle high and low as the shutter rotates Red DISTRIBUTOR SWITCHING TRANSISTOR 42 Basic Component Testing This chapter describes a computer controlled sensor and actuator system typically found on today s automobile Test procedures are also provided for the basic groups of electrical input and output components commonly found in a computer controlled automotive system The test procedures are due to the complexity of components general theory tests Be sure to consult the vehicle service manual for component schematics and test specifications APO RANGE HOLD A xorem E E gt om RPM AC CN Ch C C F c F VORPM 43 Basic Component Testing Computer Controlled Systems A need for better fuel economy and lower emissions resulted in today s automobiles utilizing computer controlled functions that were previously activated by mechanical electrical and vacuum devices Computerized vehicle control systems are made up of
23. esting Ignition System Tests Cont d 5 Pick up Coil Resistance 2 Voltage Test V The Resistance test checks for open circuits or high resistance The Voltage test compares volt age output to resistance Test Procedure Set the rotary switch to the Resistance Q Insert Black lead in COM terminal Red lead in V O RPM terminal Connect the test probes to the pick up coil leads see illus Resistance Specifications The majority of the pick up coils will test between 500 15000 s resistance See manufacturer s specification for required range Set rotary switch to Volts Press the Alternate Function button to select AC Crank engine 10 15 seconds at normal speed measure voltage Resistance Test Voltage Output C Resistance Q on a good pick DE up coil will match AC output volt SS age Ex 950 Q s 950mV SLT output Resistance can be good but voltage low if the magnet has lost magnetism or if the reluctor is too far from the stator Air gap 41 Basic Diagnostic Testing Ignition System Tests Cont d 6 Hall Effect Sensor Voltage Test V This test checks for switching action in any Hall Effect sensor Ignition RPM Crankshaft etc Set the rotary switch to the Voltage V position Insert Black lead in COM terminal Red lead in V O RPM terminal Connect the Black test probe to the negative post on the batt
24. ge e Set the rotary switch to voltage e Connect the positive lead to the positive battery terminal e Connect the negative lead to the negative battery terminal WA mA C F OF COM VORN ROO om ET AUTO POWER OFF 10A_ AN Disable the ignition crank the engine for 15 seconds Check the display A reading of Red 4 less than 9 60V 70 F indicates 4 cm a weak battery Recharge replace before testing VOLTAGE LOAD TEST Battery air Reading Temperature 10 0V 90 F 33 C ey BO FETC TO RET C 60 F 16 C Note 50 F 10 C For each 10 above or below 70 add 40 F 4 C or subtract 0 1 volt 30 F 1 C Battery temperature can be checked 20 F 7 C with the meter temperature probe 27 Basic Diagnostic Testing Voltage Drop Testing Resistance What is it Resistance is an opposing force created by a circuit or component to the flow of electrical current There is a small amount of natural resistance when voltage flows through wires switches grounds or connections The resistance increases beyond acceptable lim its if corrosion develops fittings become loose or wires fray Re sistance increases each time something such as wire a switch connections or the ground are added in the circuit Maximum Voltage Drop Voltage Drop What is it Maximum voltage drop should Voltage drop is the difference in not be more
25. inal Start the engine and hold a 1500 RPM A reading of 13 1 15 5 volts is an acceptable charging rate 35 Basic Diagnostic Testing Charging System Tests Cont d 3 Alternator Amperage A Output Battery This test checks for alternator charging rate efficiency at the battery Connect Current Clamp leads to the meter Connect the Current Clamp around the negative or posi tive 4 battery cable Set the rotary switch to the Voltage setting Note 1mV 1Amp Make sure all vehicle accesso ries are turned OFF Start the engine and hold at 1500 RPM The amperage reading should be 5 amps or better Note The current clamp measures amps in the direction of electrical flow Make sure the arrow on the clamp is pointed in the direction of the current flow in the cable Quick Test Place the clamp on the battery cable then turn the headlights on If the reading is not negative disconnect the clamp turn it over and reconnect 36 Basic Diagnostic Testing Ignition System Tests 1 Ignition Coil Primary Resistance Test 2 This test checks primary winding resistance Important Test the ignition coil cold and hot Set the rotary switch to the Resistance Q setting Insert Black lead in COM terminal Red lead in V Q RPM terminal Disconnect the coil from the vehicle wiring harness Note The res
26. ions e Electrical Specifications Introduction Contents uvigexs oq Tor e EN Satetycasni eh iluuoage eiue e be ER PUR REA REPERI Getting Started Meter Bases m Digital and Analog display eee e Function and Range Select ssssssssssseeeeeeneeen nenne 8 Pash button Functions Alternate Function Range Select ume het iinet eatin tees 9 Data Hold Hold MEER aga NG EROR ee ike eid ace autre 9 Meter Functions Voltage 3e e e RD e T 10 Resistance scsi a oett aT 11 Audible Continuity er oer iiie en 12 Diode Ghisckxa uiua EDS REGNIS BENEE 13 Temperature AA NA Eee ette 14 FOQUENCY E E 15 RPM 3d0RPM umm a LALA eA 16 Duty Cycles ee le Se Aman 17 Dwell naapakan AA tto e he o reto f des 18 AC or DG Current cs MAGSAING Gan 19 Maintenance Fuse and Battery Replacement seseee 20 Trouble Shooting 2 niece eei ete nop erts 21 Basic Diagnostic Testing eeeeeeeeeeeeeeeeeeenen nne 22 Electrical System Diagnostice sssseseeene 23 Battery Testing 1 Battery Test Surface Discharge sssssssse 24 2 Static Battery test No Load seeseesse 25 3 Battery Test Parasitic Load seeeeesesssssss 26 4 Battery Test Load sssI 27 Voltage Drop Testing eeeeeeeeeeeene
27. is still toggled ON 21 Basic Diagnostic Testing This chapter leads you through a systematic series of tests that check the vehicle electrical system These tests should be performed before testing individual components Ma eo Range vou zw 22 gt t e RPM AC C n e oF E IR 2 F hw Jooode 183 mr Cc oF VORPM FUSED 10A 60sec MAX 22 Basic Diagnostic Testing Electrical System Diagnostics It is important to diagnose a vehicle electrical problem thoroughly and efficiently The series of tests that follow check primary areas that are respons ible for the majority of the electrical problems found in an automobile Perform these basic tests first even if a vehicle has a trouble code set in the computer A component malfunction detected by the computer can be caused by a basic ground problem in the electrical system Simply replacing a failed component will not fix the problem if a poor ground caused the component failure The tests begin by checking the main source of power and the chassis ground circuit connections Ground circuits are one of the least understood but potentially most troublesome areas of automotive electronics An excessive voltage drop in a ground circuit effects the entire electrical circuit This is why it is important to make sure the basic circuits are in good shape before checking trouble codes and components 23 Basic Diagnostic Testing Ba
28. istance in the meter leads must be subtracted to get an accurate measurement at the 1 0 FUSED coma COM MAX A 00 2 0 range Black Red Connect the negative lead to the negative terminal on the coil Connect the positive lead to the positive B terminal on the coil Typical measurements are be tween 1 0 2 0 O s Consult the manufacturer s specifications for required resistance measurements GM DIS Coil Type Il Both primaries located on back of coil 37 Basic Diagnostic Testing Ignition System Tests Cont d 2 Ignition Coil Secondary Resistance Test 2 This test checks secondary winding TOS resistance E Important Test the ignition coil cold and hot e Set the rotary switch to the Resistance 2 setting Insert Black lead in COM terminal Red lead in V O RPM terminal AUTO POWER OFF HA mA C F DA VORM coma COM MAX Disconnect the coil from the vehicle wiring harness Connect the negative lead to the high tension terminal on the coil Connect the positive lead to the positive B terminal on the coil Typical measurements are between 6 000 30 000 O s Consult the manufacturer s specifications for required resistance measurements GM DIS Coil Type II 38 Basic Diagnostic Testing Ignition System Tests Cont d 3
29. its at 18 C to 28 C 65 F to 83 F with relative humidity up to 70 RPM Tach Range 600 4000 4000 12000 x10RPM Resolution 1RPM Effect Reading gt 600 RPM Accuracy 2 rdg 4 dgts Overload protection 500VDC or RMS AC DUTY CYCLE Range 1 0 to 90 0 Resolution 0 1 Pulse width gt 100us lt 100ms Accuracy 2 rdg 5 dgts Overload protection 500VDC or RMS AC DWELL ANGLE No of Cylinders 4 5 6 8 Range 0 90 0 4CYL 0 72 0 BCYL O 60 0 6CYL O 45 0 8CYL Resolution 0 1 Accuracy 2 rdg 5 dgts Overload protection 500VDC or RMS AC TEMPERATURE Ranges 20 C 1000 C 4 F 1832 F Resolution 0 1 C 0 1 F Accuracy 2 0 4 C 20 C 10 C 1 0 3 C 10 C 200 C 3 0 2 C 200 C 1000 C 2 0 8 F 4 F 50 F 1 0 6 F 50 F 400 F 3 0 4 F 400 F 1832 F Sensor type K type thermocouple Overload protection 500VDC or RMS AC 60 Specifications Electrical Specificatios Cont d DC VOLTAGE Autoranging Ranges 400mV 4V 40V 400V 600V Resolution 0 1mV Accuracy 1 096 rdg 2 dgt Input impedance 400mV 100MQ 4V 10MQ 40V 600V 9 1MQ Overload protection 600VDC or AC rms AC VOLTAGE Autoranging Ranges 400mV 4V 40V 400V 600V Resolution 0 1mV Frequency response 50Hz to 500Hz Accuracy 2 0 rdg 5 dgts 50 100Hz on 400mV range 2 0 rdg 5 dgts Input impedance 400
30. mV 100MQ 4V 10MQ 40V 600V 9 1MQ Overload protection 600VDC or AC rms CURRENT Ranges 400uA 4000uA 40mA 400mA 10A Resolution 0 1UA DC accuracy 2 0 rdg 2 dgts on 400uA to 400mA ranges 3 0 rdg 3 dgts on 10A range AC accuracy 2 5 rdg 5 dgts on 400uA to 400mA ranges 3 5 rdg 5 dgts on 10A range Frequency response 50Hz to 500Hz Voltage burden 0 2V on 400uA 40mA ranges 2V on 4000uA 400mA ranges Input protection 0 5A 500V fast acting ceramic fuse on uA mA input 10A 500V fast acting ceramic fuse on 10A input RESISTANCE Autoranging Ranges 4000 4kO 40kQ 400kO 4MO 40MQ Resolution 0 12 Accuracy 1 5 rdg 4 dgts on 4000 to 400kQ ranges 2 5 rdg 4 dgt on 4MQ range 5 0 rdg 5 dgt on 40M O range Open circuit volts 0 45Vdc 1 2Vdc on 4002 range Overload protection 500VDC or RMS AC 61 Specifications Electrical Specificatios Cont d FREQUENCY Autoranging Range 4kHz 40kHz 400kHz Resolution 1Hz Accuracy 0 1 rdg 3 dgts Sensitivity 3 5V RMS Minimum pluse width 5 2 5us Duty cycle limits gt 30 and lt 70 Overload protection 500VDC or RMS AC DIODE TEST Test current 1 0mA appreximate Accuracy 3 096 rdg 3 dgts Resolution 10mV Audible indication 0 25V Open circuit volts 3 0Vdc typical Overload protection 500VDC or RMS AC AUDIBLE CONTINUITY Audible indication Less than 250 Response time 500mQ Overload protection 500VDC or RMS
31. manual diagnostic CYLINDER SELECT ERROR precedures repairs and specifications EST GROUNDED OS SENSOR LEAN 02 SENSOR RIGH PROM ERROR Note Typical codes are shown as examples only 46 Basic Component Testing Computer Controlled Systems Cont d Component Testing Component testing with a meter generally requires detailed schematics and specifications that are provided by the manufacturer The following section provides general information for the main groups of sensors input devices and actuators output devices The primary input devices sensors are Temperature sensors 2 wire devices 3 wire devices Oxygen sensor Pressure sensor Primary output devices actuators are a form of an electromagnet that is either ON or OFF The ON OFF signal in general will be in one of three configurations ON or OFF only switch Duty cycle measured in percent of high or low time or dwell degrees mixture control solenoid 47 Basic Component Testing Computer Controlled Systems Cont d Duty Cycle What is it Duty Cycle is the percentage 95 of time a voltage is positive campared to negative ON com pared to OFF For example duty Positive gt cycle measurements are used for Negative Mixture Control solenoids The amount of ON time is measured Dury as a percent of the total ON OFF Cyc e cycle The meter can read the negative or positive slope and display it
32. nal Touch the Black probe to ground or to the negative circuit Touch the Red probe to the circuit coming from the power source IMPORTANT voltage must be measured in parallel Red probe measuring circuit from power source gt Accuracy Selection of a lower rang will move the decimal point one place and increase the accuracy of the reading An OL Over Limit display means the range is too low select the next higher range AUTO POWER OFF CF VORPM Black Red A WARNING 10 When measuring voltage be sure the Red test lead is in the terminal marked V If the test lead is in an Amp 10A or uA mA terminal you may be injured or the meter damaged Getting Started Meter Functions Resistance 2 IMPORTANT If you are testing an application that has capacitors in the circuit be sure to turn the power OFF on the test circuit and discharge all capacitors Accurate measurement is not possible if external or residual voltage is present gt Select the resistance Q setting with the rotary switch Select the resistance Q f LA A a range with the button labeled RANGE if a more accurate measurement is desired Insert Black lead in COM terminal Red lead in V Q RPM terminal Touch the test lead probes across the resistor to be tested Getting Started Meter Functions Audible Continuity e IM
33. neeenen nnn 28 1 Negative Engine Ground sseeeeeeeee 29 2 Negative Chassis Ground ssseeesess 30 3 Battery Power to Starter Solenoid 31 4 Battery Power to Complete Starter Circuit 32 Starter Motor Testing 1 Starter Current eseeseseeneeeneen 33 dl JI Introduction Contents Cont d Basic Diagnostic Testing Cont d Charging System Tests 1 Battey cec lebe nite mtt GN 34 2 Alternator Voltag Output Loade sess 35 3 Alternator Amperage A Output Battery 36 Ignition System Tests 1 Ignition Coil Primary Resistance Test Q 37 2 Ignition Coil Secondary Resistance Test Q 38 3 Secondary Ignition Wire Resistance Test Q 39 4 Distributor Cap Rotor Resistance Test Q sssss 40 5 Pick up Coil Resistance Voltage Test Q 41 6 Hall Effect Sensor Voltage Test V 42 Basic Component Testing eeeeeeeeeeeeeeeeen 43 Computer Controlled Systems eese 44 Basic Diagnostics for the Computer Controlled Engine 45 Self Diagnostic Computer Systems ssssssesssssss 46 Component Testing
34. o not start the engine AUTO POWER OFF HA mA CF toma COM VORPII D Observe the bar graph display The voltage drop should change as the position of the signal arm on the potntiometer moves sig nal sweep Red 4 Refer to the manufacturer s specifications If the voltage change is not within specifica tions look for sources of resistance due to poor connec tors connections or breaks in the wiring 55 Basic Component Testing Component Tests Input Cont d 4 Oxygen Sensor 02 Test The Oxygen Sensor samples the amount of Oxygen in the exhaust stream The voltage produced by the O2 sensor is a direct ratio to the oxygen level in the exhaust stream This voltage is used by the computer to change the air fuel mixture The test will check oxygen sensor signal output levels Disconnect the vehicle wiring harness at the sensor Install a jumper wire Select the Voltage range with the rotary switch Insert Black lead in COM terminal Red lead in V O RPM terminal Connect the test probes in par allel Positive to the jumper wire negative to the engine ground Vehicle engine must be running at operating temperature fast Black idle at 2 000 RPM for two min utes Voltage readings should move between 0 2 lean and 0 8 rich The average DC voltage should be around 0 50 56 Basic Component Testing
35. ode 4 to 4 Good 0 4 to 0 9V Cr ECCT 0 4 to EE S Bad OL OL 000V 000V Getting Started Meter Functions Temperature C F ARA AA ARA AA AA Temperature a IMPORTANT To avoid heat damage to the meter keep it away from sources of very high temperature The life of the temperature probe is also reduced when subjected to very high temperatures operating range is 4 F to 1832 F gt Select desired temperature unit of measurement C F with the rotary switch E Connect the K type thermocouple to a TEMP adapter Match the polarity of the adapter to the polarity of the thermocouple gt Connect the TEMP adapter to the VQ and COM jacks Touch the end of the temperature sensor to the area or surface of the object to be measured 14 Getting Started Meter Functions Frequency Hz gt Set the rotary switch to the frequency range that gives the most accurate measurement reading Insert Black lead in COM terminal Red lead in V O RPM terminal Connect the Black test probe to ground Connect the Red test probe to the signal out wire of the sensor to be tested AUTO POWER OFF HA mA C F foma COM VORPW Black Ground Side Signal Out Side Signal In Side 15 Getting Started Meter Functions RPM X10RPM Select the RPM range with the rotary switch
36. post A reading of less than 12 4V indicates an undercharged battery Recharge before testing NO LOAD TEST Meter Battery Reading Charge Note 5 5 12 2V Leave the battery cable unhooked and 12 0V proceed to the test on the following page 25 Basic Diagnostic Testing Battery Testing Cont d 3 Battery Test Parasitic Load This test checks for excessive parasitic drain on the battery Turn the ignition switch and all accessories OFF Important Do not start the vehicle during this test meter damage may result Set the rotary switch to 10A LA 49 C 4 Insert the positive lead into the 10A meter terminal OF FUSED Disconnect the battery positive cable Connect the positive lead to Ha Red Black the positive battery terminal Connect the negative lead to the disconnected positive battery terminal Parasitic draw should not exceed 100mA If there is excessive draw remove the circuit fuses one at a time until the excessive draw is located Also check the non fused applications such as head lights computer relays and capacitators in the instrument panel Reconnect the battery cable for the next test 26 Basic Diagnostic Testing Battery Testing Cont d 4 Battery Test Load This test checks the battery s capacity to deliver sufficient cranking volta
37. probes to the Signal Line and to the Ground refer to manufacturer s sche matic Watch the bar graph display the Ohms reading should change as the signal arm on the potentiom eter is moved signal sweep Typical potentiometer applications are Throttle position Sensor TPS Exhaust Gas Recirculation valve position sensor EVP Black Vane Air Flow Meter VAF 53 Basic Component Testing Component Tests Input Cont d Potentiometers Variable Resistance 3 wire Tests Reference Voltage Tesr Disconnect the vehicle wiring harness at the sensor Select the Voltage range with the rotary switch Insert Black lead in COM terminal Red lead in V O RPM terminal Connect the test probes in par allel Positive 4 to the com puter reference volatge circuit negative to the negative sys tem ground circuit from the sen sor Turn the ignition switch ON do not start the engine Watch the bar graph display Read ing should be 5 9 volts check the manufacturer s specifications 54 Basic Component Testing Component Tests Input Cont d Potentiometers Variable Resistance 3 wire Tests Voltage Change Connect jumper wires between the connector and the sensor Connect the test probes in par allel Positive to the signal line negative to the ground circuit Turn the ignition switch ON d
38. rtant Repeat this test when Clean and inspect the battery the engine is thoroughly warmed cable connections and the ground up Heat expansion of metal may test again cause resistance to increase 29 Basic Diagnostic Testing Voltage Drop Testing Cont d 2 Negative Chassis Ground This test checks for chassis ground efficiency Set the rotary switch to Voltage Establish the base voltage that you will compare test voltage against see base voltage Volt Drop Test 1 e Connect the positive lead to the point on the fender fire wall or vehicle frame where the ac Y cessory ground is fastened AUREUS OFF HA mA c F VORPM Connect the lead to the negative battery terminal Turn all of the accessories ON bright lights A C fan high rear window defroster wind shield wipers etc Red 4 Disable the ignition so the en Mee gine doesn t start crank the gt engine for 2 3 seconds The example shown has 2 con nectors 1 wire 1 ground and 1 terminal to battery post A volt age drop of more than 0 5 volts would indicate a poor ground circuit Important Repeat this test when Clean and inspect the battery cable the engine is thoroughly warmed connections and the ground test up Heat expansion of metal may again cause resistance to increase 30 Basic Diagnostic Testing Voltage Drop Testing Cpmt d 3 Battery Pow
39. s Wear an eye shield when testing or repairing vehicles Exceeding the limits of this meter is dangerous It will expose you to serious or possibly fatal injury Carefully read and understand the cau tions and the specification limits of this meter Voltage between any terminal and ground must not exceed 600V DC or AC Use caution when measuring voltage above 25VAC or DC Circuit tested must be protected by a 10A fuse or circuit breaker Do not use the meter if it has been damaged Do not use the test leads if the insulation is damaged or if metal is exposed e Use current clamps to measure circuits exceeding 10A Introduction Safety Cont d A Danger Avoid electrical shock Do not touch the test leads tips or the 9 circuit being tested Do not try a voltage measure ment with the test leads in the 10A or the uA mA terminal When testing for the presence of voltage or current make sure the meter is functioning correctly Take a reading of a known voltage or current before accepting a zero reading Choose the proper range and function for the measurement Do not try voltage or current measurements that may exceed the ratings marked on the Function Range switch or terminal When measuring current connect the meter in series with the load Never connect more than one set of test leads to the meter Disconnect the live test lead before disconnecting the common test lead The uA mA
40. sic Component Testing Computer Controlled Systems Cont d Self Daignostic Computer Systems One of the functions of the vehicle computer is to record fault codes produced when a sensor or actuator fails These failures are usually displayed as a Current Code or as an History Code Current Codes are further grouped into Hard Failures and Intermittent Failures Be aware however that some vehicle manufacturers use different terminology and older vehicles do not have all of the groups of codes described Current Codes are faults that are active Hard Failure causes the dash Check Engine light to remain ON Intermittent Failure causes the dash Check Engine light to flicker and then go OFF after a short period of time Generally the trouble code stays in the computer memory History Codes are stored codes for faults that have occurred in the past DESCRIPTION Failure Codes 02 SENSOR CIRCUIT When a failure is detected by the COOLANT TEMP HI computer it stores the information COOLANT SENS LO TMP in the form of Fault Codes also TPS VOLTAGE HI known as Trouble Codes or Service TPS VOLTAGE LOW Codes These Fault Codes are MANIFOLD AIR TEMP HI usually a two or three digit numger that identifies the electrical circuit MANIFOLD AIR TEMP LO effected Once these codes have EGR VACUUM ERROR been read the vehicle repair can be MAP ERROR started Be sure to closely follow the MAP SEMSOR HIGH vehicle service
41. ttery Testing 1 Battery Test Surface Discharge Note Remove the positive and negative battery cables and thoroughly clean the cable terminals and the battery posts Reassemble and begin testing The ignition switch must be OFF to prevent damaging the vehicle computer when connecting or disconnecting battery cables This test checks for a low current ic discharge across the battery case Set the rotary switch to Voltage Connect the negative lead to the negative battery post Touch the positive lead to the battery case around the positive battery post Do not touch the post A reading of more than 0 5V indicates excessive surface discharge Dirt moisture and corrosion are a cause of surface discharge Clean the battery with a baking soda and water solution Do not allow the solution to get into the battery 24 Basic Diagnostic Battery Testing Cont d Testing 1 Static Battery Test No Load This test checks for battery charge state Turn the headlights on for 15 seconds to dissipate battery surface charge IMPORTANT The ignition switch must be OFF when connecting or disconnecting battery cables to prevent damaging the vehicle computer Disconnect the negative battery terminal Set the rotary switch to Voltage Connect the positive lead to the positive battery post Connect the negative lead to the negative battery
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