Audio System Troubleshooting, Delco/Delphi VN, VHD
Contents
1. A Tip for radio D Metal case B Tip for antenna E Negative battery cable C Metal case Measuring Points Expected Value N WARNING A amp B less than 3 5 Q CeD less than 1 0 Q When removing battery ground cable disconnect other ground cables connected to the battery first A amp D infinite such as engine ECU satellite system etc then e remove the battery ground cable Electronic modules CoB infinite may be damaged when additional grounds are ASC infinite connected disconnected without the main battery ground connected Always disconnect the main battery B amp D infinite ground last CoFEtE less than 1 0 22 The antenna and the lead in must be properly grounded for proper reception The antenna gets its ground at the mounting bracket Poor mounting of the antenna can cause poor reception and or interference To check the antenna and the lead in grounding disconnect the battery negative connector and check from the negative battery cable connector E to the lead in cable shield C at the radio Test Antenna Generally antenna systems will have very little resistance from the antenna mast to the center conductor tip where it plugs into the radio and very little resistance from the antenna base to ground However in practice it is difficult to test antennas in the VN series vehicle due to mounting locations or multiplex antenna circuitry As an alternative to complex antenna testing a simple test antenna lead in cable can be c2. Page 16 49 Volvo Trucks North America Inc Service Bulletin Measure between pin B1 RR Speaker and B2 RR Speaker Measure between pin 4 B1 RR Speaker and A8 Ground Measure between pin B2 RR Speaker and A8 Ground Measure between pin B3 RF Speaker and B4 RF Speaker Measure between pin B3 RR Speaker and A8 Ground Measure between pin B4 RR Speaker and A8 Ground Measure between pin B5 LF Speaker and B6 LF Speaker Measure between pin B5 RR Speaker and A8 Ground Measure between pin B6 RR Speaker and A8 Ground Measure between pin B7 LR Speaker and B8 LR Speaker Measure between pin B7 RR Speaker and A8 Ground Measure between pin B8 RR Speaker and A8 Ground Note If the outputs are not correct check for speakers and the wiring harness that is shorted to the ground or battery Note If the outputs are correct replace the radio receiver Test the radio receiver operation after replacement Date Group No Page 4 2004 392 09 17 49 AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC AC Voltage changing proportionally with Volume and Music 1
3. Check Battery B on Ignition line Ignition key must be in the ON or Accessory ACC position Back probe the radio wiring harness connector with Volt Ohm Meter VOM set to Volts DC Measure between pin 4 A4 B 10 5 to 16 VDC Ignition and A8 Ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Page 21 49 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 Check for proper ground Ignition key must be in the OFF position Back probe the radio wiring harness connector with VOM set Ohms Measure between pin Less than 1 Ohm A8 Ground and vehicle ground Battery Measure between pin Less than 1 Ohm A8 Ground and vehicle chassis ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Check for the Power Supply or Battery B on Park Lights Headlight switch must be ON Back probe the radio wiring harness connector with Volt Ohm Meter VOM set to Volts DC Measure between pin B 10 5 to 16 VDC A3 Park Lights and A8 Ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Note If no faults are found replace the radio receiver There are no field replaceable lamps in the radio receiver assembly Test the radio receiver operation after replacement Check for the P
4. Measure between pin Less than 1 Ohm A8 Ground and vehicle chassis Ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Note If no faults are found replace the radio receiver There are no field replaceable lamps in the radio receiver assembly Test the radio receiver operation after replacement Page 20 49 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 No Radio Receiver Face Illumination Backlighting Depending on how the vehicle is wired the brightness of the display can be adjusted by pressing and holding the SCAN DIM button until DIM and the brightness level appear on the display Rotate the AUDIO knob clockwise to increase the brightness fo the receiver display and counter clockwise to decrease it Otherwise the radio receiver should illuminate when the headlight switch is on and the display background light should automatically dim to reduce glare The dimmer switch should raise and lower the brightness of the face illumination and the display background light Check for Power Supply or Battery B Headlight switch must be ON Back probe the radio wiring harness connector with Volt Ohm Meter VOM set to Volts DC Measure between pin 4 A7 B 10 5 to 16 VDC Battery and A8 Ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action
5. e As short as possible e Total resistance of 0 2 ohms or less e Large surface area e Isolated from electrically noisy devices One diagnostic procedure calls for installing a braided ground strap from the chassis of the radio to a good grounding point As important as it is to install the good ground it is egually important to delete the previous ground at the radio If two grounds were allowed to remain it is possible to set up what is called a ground loop This occurs when there are two paths for ground return but they are not at egual potentials When this happens one actually carries a current to the radio chassis and adds it to the normal radio current Braided Grounds W3003063 Braided ground strap e Braid 10 5 in Volvo P N 176001 e Braid 19 in Volvo P N 176002 e Braid 21 in Volvo P N 176003 e Braid 8 5 in Volvo P N 176004 The audio system has small AC currents flowing in such places as the antenna system In a high frequency AC circuit the current migrates closer to and travels most efficiently near the outside surface of the conductor This is called the skin effect Because of the skin effect the better ground in the audio system is one with a larger conductive surface area This is why a braided ground strap is used where grounds do not resolve the condition such as at the base of a power antenna mast If installing a braided ground does not resolve the condition reconnect the original grou
6. test if the antenna system meets specifications or if there is an electrical noise emitter present in the vehicle Possible Causes e Poor grounding of the following e Antenna e Receiver e Some electrical components e Body panels e Defective or marginal components relays switches solenoids motors etc e Antenna lead in too close to electrical or electronic components e Opens shorts or electrical leaks in the ignition system Troubleshooting Hints e f noise is present with the radio on but goes away when the CD or cassette tape player is on it is likely that front way noise is the problem e Confirm that the antenna system is the source of noise with the test antenna See Test Antenna page 46 e Always verify grounding first If more than one component interferes poor grounding probably exists 1 Check the antenna system Antenna lead in cable must have low resistance All antenna cable connectors must be in good condition and tight Antenna base must be well grounded Lead in to radio connection must be tight and low resistance 2 Check for excess noise reaching the antenna system Pinpoint the noise source See Noise Sniffer page 40 Route the antenna cable away from electrical electronic noise circuits Check for malfunctioning electrical electronic components on the vehicle Electrically noisy devices can sometimes be filtered or suppressed Check for poor grounds or other poor co
7. the amplifier will only work with High Performance Family receivers or XTA Uplevel Family receivers Verify that the correct receiver is used e Ignition key must be in ON or ACC position Back probe the amplifier connector with a multimeter Kent Moore J39200 at the following measuring points 5 Measuring Points Expected Nalue If not correct check for blown fuse or damage incorrect Pin E11 amp B truck wiring and take appropriate corrective action Alternate ground Pin E12 amp B Alternate ground e Check for proper ground Ignition key must be in OFF position Back probe the amplifier connector with a multimeter Kent Moore J39200 at the following measuring points M ring Points E Val sat auta ems Hpecied Walle If not correct check damage incorrect truck wiring and Pin E8 Alternate ground less than 1 Q take appropriate corrective action Pin E9 Alternate ground less than 1 Q e Check speaker inputs from the stereo receiver Ignition key must be in ON or ACC position Back probe the amplifier connector with a multimeter Kent Moore J39200 at the following measuring points Measuring Points Expected Value Pin E2 Pin E3 AC voltage changing proportionately with volume Pin E1 amp Pin F1 AC voltage changing proportionately with volume Pin E4 Pin E5 AC voltage changing proportionately with volume Pin E6 Pin E7 AC voltage changing proportionately with
8. 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 Radio Receiver Will Not Retain Presets The radio receiver should remember Preset radio stations that have been programmed in by the owner The Preset radio stations are stored internally and should be recalled even if the Power Source or Battery B and the ground are removed The only exception to this rule is the Presets that are stored using the Auto Store Auto button The Auto Store Auto button automatically stores the six strongest stations on Push buttons one through six 1 6 These are temporary Presets unless the user presses the Auto Store Auto button again for two seconds then the original presets will be stored Individually select each radio station found by pressing the Auto Store Auto and press each Preset button until a beep is heard Note If no faults were found replace the radio receiver Test the radio receiver operation after replacement Page 18 49 Volvo Trucks North America Inc Service Bulletin No Sound From Some Speakers If equipped with an Uplevel Cassette or Uplevel CD there may also be an amplifier If the amplifier is hooked up and the ignition is OFF with the radio receiver ON only the speakers that are not hooked to the output of the amplifier will play The two upper rear speakers operate independently of the amplifier If the upper rear speakers do not opera
9. Does Not Operate On All Channels e Check speaker inputs from the stereo receiver Ignition key must be in ON or ACC position Back probe the amplifier connector with a multimeter Kent Moore J39200 at the following measuring points Measuring Points Expected Value Pin E2 Pin E3 AC voltage changing proportionately with volume Pin E1 Pin F1 AC voltage changing proportionately with volume Pin E4 amp Pin E5 AC voltage changing proportionately with volume Pin E6 Pin E7 AC voltage changing proportionately with volume If not correct check the radio receiver outputs and wiring harness If correct check speakers and wiring harness If all are correct replace the amplifier 7See Harness Connectors page 28 Volvo Trucks North America Inc Service Bulletin Date 4 2004 No Page 392 09 33 49 e Check speaker outputs from the amplifier Ignition key must be in ON or ACC position Back probe the amplifier connector with a multimeter Kent Moore J39200 at the following measuring points Measuring Points Expected Value Pin E13 amp E14 AC voltage changing proportionately with volume Pin F10 amp F11 AC voltage changing proportionately with volume Pin E15 amp E16 AC voltage changing proportionately with volume Pin F13 amp F14 AC voltage changing proportionately with volume Pin F2 amp F3 AC voltage changing propo
10. Page Service Bulletin 4204 392 09 48 49 Diagnostic Test Kit Test CD Cassette Tape The Delco Audio Diagnostic Kit Kent Moore J39916 A can be used to diagnose several audio complaints The test CD cassette tape will provide the technician with test tones for the following test Note An instruction booklet is included with the kit Function Bass subwoofer test Mid range speaker tests Door tweeter test All speaker test Speaker buzz and rattle test Noise diagnosis Coaxial speaker diagnosis Motor speed test N CAUTION Improper use of this diagnostic CD cassette tape can result in speaker or amplifier damage Always begin testing procedures at minimum volume working up to an appropriate level Each signal will be played for five minutes starting with the low frequency tone Use the fade and balance controls to evaluate the speakers For example when the test signal begins fade full front and check the speaker response of the right and left speakers with the balance control Then fade full rear and check the rear speakers in the same manner There should be enough time to check all speakers with each signal If the signal ends and the test is not completed simply replay the necessary signal Note Always compare the front speakers to front and rear speakers to rear Don t compare the front speaker to rear speaker because they could be different speakers or their mounting environment could cause them to so
11. To unlock a LOCKED radio Note Pause no more than 15 seconds between the steps 1 Press SEEK 5 The display will show 0000 2 Press SEEK 5 as many times as needed to make the last digits agree with the secret code 3 Press TUNE 6 as many times as needed to make the first digits agree with the secret code 4 Confirm that the code on the display matches the code you have chosen 5 Press BAND 1 The display will show SECURE indicating that the radio is operating and the THEFTLOCK is active Note If the display shows LOCKED the incorrect code was entered Repeat steps 1 5 Page 2 49 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 If the wrong code is entered 8 times InoP will appear on the display You will have to wait an hour with the ignition ON before you can try again When you try again you will only have three more chances 8 tries per chance to enter the correct code before InoP appears again To unlock a LOCKED radio when the code is not available To obtain an unlock code for a LOCKED radio when the entered code is not available contact the local Volvo Dealer or call technical support at 1 800 52 VOLVO Page 3 49 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 4 49 Weather Band and High Performance Family Harness Connectors 4 Speak
12. act like an open circuit to a DC circuit Capacitors will act like a resistance to an AC circuit and therefore short undesirable alternating currents to ground Capacitors may be packaged in several ways Electrolytic capacitors by themselves will be marked with positive and negative leads and must be installed with the correct polarity W3003066 220 uF 50 V capacitor P N 176007 Fuse block capacitor P N 176008 Feed through capacitor P N 176009 0 47 uF capacitor P N 176010 Ps W N Feed through type capacitors have already taken care of connecting the capacitor in parallel with the correct polarity To install the feed through capacitor open the DC circuit then install the device in series The feed through capacitor body must be connected to a good ground for the capacitor to be effective Inductors W3003070 L Inductor Inductors sometimes called a choke are windings of wire To a DC circuit this looks like a short but to an AC circuit this looks like a high resistance Thus AC is effectively blocked while DC passes normally Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 44 49 Filters W3003069 Inductors are often used with a capacitor to form a filter Each end of the inductor L is connected in series to the DC circuit and the remaining end of the capacitor C to ground This forms a double tap for AC that may be traveling the DC circuit The capacitor will short some
13. can then be used to probe and search out hot spots Procedure 1 While listening to the complaint noise disconnect the antenna and plug the sniffer into the antenna socket 2 Turn the radio volume up 3 When searching for the noise source keep fingers off of the probe otherwise erroneous results will be received W3003062 1 Noise 2 Wire from harness 3 Sniffer When checking for noise on a wire the best results will be achieved when the sniffer is placed parallel to the wire The sniffer can also be used to determine from what area of the dash the noise is being generated onto the antenna It must be noted that the sniffer will also locate normal hot spots However a technician who becomes familiar with the sniffer s capability will find it the most useful diagnostic tool in noise suppression work Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 41 49 Noise Suppression The correct application of noise suppression and devices is very important Connecting a noise suppression device in the wrong place or incorrectly can cause a condition to worsen circuits to become inoperative or incorrect operation Good Grounds While a good DC ground is often called for it is most important to realize just what makes a good ground in an audio system Diagnostic procedures will often call for testing for a good ground A good ground in the audio system is one with the following qualities
14. interference These noises are often heard when a particular accessory or system is operated Diagnose back way noise after eliminating front way or side way noise Possible Causes e Poor grounding of the receiver measure with the antenna lead in disconnected e Non suppressed electrical components e Poorly routed wires e Defective electrical components or defective suppression components Troubleshooting Hints e Determine if noise is present only if the engine is running or when certain electrical components are operating Removing fuses one at a time can help isolate the noise source e Grounds shared between electrically noisy components and audio components can be noise sources Establish new grounds if necessary e Switch pops are suppressed using capacitors See Switch Pop Suppression page 45 e Capacitors or filter packages are most effective when installed at the noise source Whines squeals or buzzes are best suppressed using filter packages See Capacitors page 43 and Filters page 44 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 39 49 Harness Noise W3003060 Speaker harness noise entry 1 Radio receiver 2 Speaker Harness noise is any noise induced into speaker wires or any low level audio signal wire used to connect audio components Possible Causes e Magnetic or electronic fields reaching the low level audio lines e Noisy wiring or compone
15. is upside down in CD Player LOAD Load unload motor problem NO CD No CD inserted or communication problem TRACKING Optics loss of tracking control or disc is upside down in CD Player CD Changer Errors Radio receiver displays error codes when problems are detected relating to the CD Changer operation COMM ERR Communication Error device pressed is not responding or cable not plugged in properly FOCUS Optics focus error or disc is upside down in magazine MOTOR ER Load unload motor problem NO CDX Empty magazine or communication problem check CDX harness NO DISC Time out displayed when CD Magazine cartridge is empty TRACKING Optics loss of tracking control Note Neither the Base Stereo or Base Cassette will work with an Amplifier or CD Changer An Uplevel Cassette or CD is required to utilize these types of systems Uplevel Plays for One hour and quits with Ignition ON These diagnostics are valid for the receiver on the Uplevel Sound System Uplevel supports a one hour play mode with the ignition off Check for Battery B on Ignition line Ignition key must be in the ON or ACC Accessory position Back probe the radio wiring harness connector with the Volt Ohm Meter VOM set to Volts DC Measure between pin A4 Ignition and A8 Ground B 10 5 to 16 VDC If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Page 15 49 Volvo Trucks
16. normal Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 27 49 Internal Faults If the radio on the stereo receiver works properly but the CD player does not there is likely an internal fault in the CD player There are no field repairs available for the CD player Replace if necessary Diagnostic Kit test The Delco Audio System Kit Kent Moore J39916A can be used to diagnose CD player complaints See Diagnostic Test Kit page 48 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 28 49 Amplifier Harness Connectors Amplifier Harness To Amplifier Amplifier Harness To Stereo Receiver Cavity Circuit Function Cavity Circuit Function E1 499RA RHS Front Input 1 499RA RHS Dash Speaker E2 499LA LHS Front Input 2 499LA LHS Dash Speaker E3 499LB LHS Front Input 3 490 12 V Supply E4 498RB RHS Rear Input 4 141 Dimmer Control E5 498RA RHS Rear Input 5 498RA RHS Door Speaker E6 498LA LHS Rear Input 6 498LA LHS Door Speaker E7 498LB LHS Rear Input 7 498LB LHS Door Speaker E8 oC Ground 8 498RB RHS Door Speaker E9 0C Ground 9 0C Ground E11 490 12 V Supply 10 90A Light Control E12 490 12 V Supply 11 492 12 V Supply E13 L4 LHS Dash Speaker 12 499LB LHS Dash Speaker E14 L4 LHS Dash Speaker 13 499RB R
17. or verify a speaker rattle or buzz Tone two is also a sweep but freguency change is at much slower rate This can be used in the repair of a speaker rattle or buzz If the problem has already been isolated the fade and balance controls can be set to the proper location and the test tones can be played in the specific problem area Noise Diagnostic This portion can be used for noise diagnostics such as alternator whine switch pops etc This portion of the diagnostic CD cassette tape may be used in conjunction with the audio diagnostic section in the service manual provided with the test kit Motor Speed There is a 2 minute time period marked in a section of the diagnostic tape for the purpose of checking the cassette tape motor speed This portion of the diagnostic tape can be used to verify or resolve problems when a customer complains that the audio from the cassette tape sounds abnormal In some cases improper tape motor speed can cause abnormalities If the time taken for this test is between 1 minute and 56 seconds to 2 minutes and 1 second the tape motor speed is within tolerance
18. the combination tone you will be able to guickly diagnose overall audio performance in a vehicle This tone can be used for numerous audio problems such as distorted or no sound from speaker s Listening to the combination tone you should be able to hear three distinct sounds A low pitch steady tone of 50 Hz a medium frequency warbling tone of 500 Hz and a high freguency hiss or cricket type of sound about 9 000 Hz Concentrate on the appropriate element of the test signal low medium or high as you listen to the different speaker locations by means of the fade and balance control This tone can be an excellent signal to use in the diagnosis of coaxial speakers For example if a coaxial speaker is not functioning properly a direct comparison of the right to left speaker or vice versa can determine if the tweeter or woofer in the speaker assembly is inoperative Also when using the combination tone comparative AC voltage measurements can be made on the speaker terminals provided the fade and balance controls are in the detent position With these voltage measurements a determination can be made in the diagnosis of speaker or amplifier If the amplifier system of the vehicle is operating normally the AC voltages should be very close or the same in value Speaker Grill Rattle Test This portion of the CD can be used to diagnose speaker and grill rattles The first test is two variable freguency tones played back to back which can help you find
19. volume If not correct check the stereo receiver outputs or wiring harness If correct check speakers and wiring harness If all are correct replace the amplifier 5See Harness Connectors page 28 Volvo Trucks North America Inc Service Bulletin Date 4 2004 392 09 No Page 31 49 e Check speaker outputs from the amplifier Ignition key must be in ON or ACC position Back probe the amplifier connector with a multimeter Kent Moore J39200 at the following measuring points Measuring Points Expected Value Pin E13 amp Pin E14 AC voltage changing proportionately with volume Pin E15 amp Pin E16 AC voltage changing proportionately with volume Pin F2 amp Pin F3 AC voltage changing proportionately with volume Pin F4 amp Pin F5 AC voltage changing proportionately with volume Pin F6 amp Pin F7 AC voltage changing proportionately with volume See Harness Connectors page 28 Pin F10 amp Pin F11 AC voltage changing proportionately with volume Pin F13 amp Pin F14 AC voltage changing proportionately with volume Pin F15 amp Pin F16 AC voltage changing proportionately with volume If not correct replace the amplifier If correct check the wiring to speakers and check the speakers Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 32 49 Amplifier
20. 8 VDC 1 2 B 5 25 to 8 VDC Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 No Radio Receiver Display Illumination The radio receiver displays the Time of Day when the receiver is OFF The radio receiver display should illuminate when the Ignition key is in the ON or Accessory ACC position With the ignition off the receiver can be turned on by pressing the Power PWR button or the ON AUDIO knob This activates the one hour timer of the receiver The receiver turns off after one hour The timer can be reactivated by pressing the Power PWR button or the ON AUDIO knob again Check for Power Supply or Battery B Measure between pin 4 A7 B 10 5 to 16 VDC Battery and A8 Ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Check for Battery B on Ignition line Ignition key must be in the ON or Accessory ACC position Back probe the radio wiring harness connector with the Volt Ohm Meter VOM set to Volts DC Measure between pin 4 A4 B 10 5 to 16 VDC Ignition and A8 Ground Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Check for proper ground Ignition key must be in the OFF position Back probe the radio wiring harness connector with VOM set Ohms Measure between pin Less than 1 Ohm A8 Ground and vehicle ground Battery
21. AC to ground while the inductor will block any remaining AC Filter packages can be especially useful in suppressing noise caused by a constant AC interference Such interference can be caused by an electric motor W3003067 1 Component battery or ignition feed 2 Capacitor ground lead Try grounded and ungrounded 3 Filter P N 176011 4 Splices 5 Noisy electrical component Filter performance is polarity sensitive Therefore the effectiveness of the filter is dependent on whether the AC reaches the inductor or the capacitor first The filter 2 is designed to be most effective when the end with the capacitor ground is connected toward the source of electrical noise Install the filter in this polarity first If the noise level is still not satisfactory try disconnecting the capacitor ground In some cases if the first two connections do not eliminate the noise try reversing the filter polarity and grounding the capacitor lead Volvo Trucks North America Inc Service Bulletin Switch Pop Suppression Direct switch activated device 1 Switch 2 Load C1 C2 and C3 0 47 uF capacitor P N 176007 Date Group No Page 42008 392 09 45 49 Relay activated device Relay Coil Activator switch Switch Load 01 ON 1 Determine which switch is causing a pop when activated O a A WwW N the component Diagnostic Test Kit Install a 0 47 uF capacitor C1 as shown above Determine if the compon
22. HS Dash Speaker E15 L6 LHS Door Speaker E16 L6 LHS Door Speaker F1 499RB RHS Front Input F2 R4 RHS Dash Speaker F3 R4 RHS Dash Speaker F4 S2 Subwoofer Coil 2 F5 S2 Subwoofer Coil 2 F6 R6 RHS Door Speaker F7 R6 RHS Door Speaker F10 S1 Subwoofer Coil 1 F11 S2 Subwoofer Coil 1 F13 R RHS Rear Wall Speaker F14 R RHS Rear Wall Speaker F15 L LHS Rear Wall Speaker F16 L LHS Rear Wall Speaker Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 29 49 Wiring Harness W3003443 Amplifier Connectors Upper harness Connectors Lower harness Connectors O 0 Pf W N The amplifier harness is a two piece harness The harness runs from 2 connectors at the stereo receiver to 2 connectors behind the left kick panel The upper harness runs from the 2 connectors behind the left kick panel up the left A pillar across the cab under the lower headliner to the amplifier and a connector for the rear speakers Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 30 49 No Amplifier Operation e Confirm operation of stereo receiver The two upper rear speakers operate independently of the amplifier If the upper rear speaker do not operate check stereo receiver harness or speakers Remember
23. North America Inc Date Group No Service Bulletin 4 2004 392 09 No Radio Receiver Operation These diagnostics are valid for the receiver in both the Basic Sound System and the Uplevel Sound System Verify that the complaint is accurate If the stereo functions but the playback device does not function refer to the Cassette Diagnostics or CD Diagnostics Check for Power Supply or Battery B Measure between pin A7 Battery and A8 Ground B 10 5 to 16 VDC If not correct check for a blown fuse or damaged incorrect wiring and take appropriate corrective action Check for Battery B on Ignition line Ignition key must be in the ON or ACC Accessory position Measure between pin 4 Ignition and A8 Ground B 10 5 to 16 VDC If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Check for proper ground Ignition key must be in the OFF position Back probe the radio wiring harness connector with VOM set to Ohms Measure between pin A8 Ground and vehicle ground Battery less than 1 Ohm Measure between pin A8 Ground and Vehicle Chassis Ground less than 1 Ohm If not correct check for damaged incorrect wiring and take the appropriate corrective action Check the speaker outputs from the radio receiver Ignition key must be in the ON or ACC Accessory position Back probe the radio wiring harness connector with VOM set to Volts AC
24. VOLVO Volvo Trucks North America Inc Greensboro NC USA This Service Bulletin replaces Service Manual 39 Delco Audio System Troubleshooting VN 12 1998 publication number PV776 TSP109859 Audio Problems Delco Delphi Service Bulletin Trucks Date Group No Page 4 2004 392 09 1 49 Audio System Troubleshooting Delco Delphi VN VHD This service information covers the Delco Delphi Audio System Troubleshooting For further information refer to Group 3 Contents e Stereo Receiver page 2 e Amplifier page 28 e Speakers page 34 e Noise page 35 e Antenna page 46 e Diagnostic Test Kit page 48 represented as accurately as possible Note Information is subject to change without notice Illustrations are used for reference only and may differ slightly from the actual vehicle being serviced However key components addressed in this information are PV776 20 002690 USA14751 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 Stereo Receiver You must read and understand the precautions and guidelines in Service Information group 30 General Safety Practices before performing Troubleshooting procedures Theftlock If the radio is in the Secure mode and the battery power is lost the radio will not operate LOCKED will appear on the display when the radio PWR button is pushed or when the ignition is turned on
25. d If the concern is with the entertainment radio is the tape or CD affected Identify when the condition occurs e Ignition key in OFF position e Ignition key in ACC position e Ignition key in ON position engine running e Engine running AM or FM band e What frequencies are affected e Is the condition on station or between stations e Does condition occur with volume turned down e Does condition vary with volume e Is condition RPM related e Does condition occur when switching an accessory on or off e Check antenna and lead in cable Does condition persist e Further test for condition at low volume with antenna disconnected Does condition persist If the condition is related to a fleet vehicle answer the following e Who installed the radio s e Were the installation guidelines followed e Is this the only vehicle which demonstrates this condition e Do similar vehicles have different antennas e Are the antennas mounted in the same location Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 36 49 Front Way Noise Front way noise is any noise that enters the audio system through the antenna system Some electrical noise is always present in the signals reaching the antenna but the antenna system cannot be filtered or suppressed To diagnose front way noise
26. dio or Amplifier 2 Ifthe Amplifier Battery Power is removed Blown Amplifier Fuse or shorted to the ground 3 Ifthe XTA Radio left front speaker outputs both and to the Amplifier left front speaker inputs are open the Amplifier will not detect the XTA Radio and therefore causing the display fault to occur LOCKED Unlock the radio using either the customer stored code or secret unlock code Note If presets were stored using the Auto Store AS when battery is removed the customer stored presets are returned to each preset button If you want them stored find the strongest stations using the Auto Store function Then press and hold the Auto Store button for two seconds Individually press and hold each preset to store them as Customer Stored Presets Tape Player Errors The radio receiver displays error codes when problems are detected relating to the Tape Player operation BAD TAPE Bad tape conditions are detected 1 Cut tape 2 Tape wound too tight 3 Pinched tape roller NO TAPE No cassette tape inserted or Eject Audio Mute selected TP CLEANER Tape Clean Indicator Clean the tape player and then press and hold the EJECT until CLN RST appears and then disappears Page 14 49 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 CD Player Errors Radio receiver displays error codes when problems are detected relating to the CD Player operation FOCUS Optics focus error or disc
27. e following checks can be performed e With a multimeter Kent Moore J39200 check the AC voltage at the A and B speaker terminals A small AC voltage should be present with the stereo receiver volume low and increase proportionately with volume increase If AC voltage is correct replace the speaker If no AC voltage is present check the wiring and the stereo receiver outputs Speakers Rattle e Isolate the problem speaker Inspect for loose or damaged speaker or grill e The Delco Audio System Diagnostic Kit Kent Moore J39916 A can be used to diagnose speaker buzz or rattle A test CD and cassette tape will provide the technician with test tones for speaker testing The stereo receiver must be eguipped with a CD player or cassette tape player to use this test kit See Diagnostic Test Kit page 48 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 35 49 Noise RFI Ouestionnaire To begin diagnosing RFI conditions it is important to understand the nature of the condition and the elements that may be involved The following guestionnaire will help determine vital pieces of information for the diagnostic process Question Yes No Is the vehicle equipped with any non factory installed electronics This includes radar detectors scanners and hand held communications devices If the condition occurs with a non factory installed radio have the radio installation guidelines been followe
28. ea 2 RSA Control Rear Seat Audio 3 N C 4 N C 5 N C 6 N C 7 N C 8 Test Pin for manufacturing use only 29 N C 3 N C 32 N C 34 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 10 49 Volvo Trucks North America Inc Service Bulletin W3006208 Rear of Radio 20 Pin Terminal Layout W3006209 Rear of Radio 36 Pin Terminal Layout Date 4 2004 Group No 392 09 Page 11 49 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 12 49 Uplevel Sound System Uplevel Cassette and CD Pin Connections N C Dim 8 Co RR Speaker RE Speaker RF Speaker Fe Speaker LE Speaker Re Speaker LA Speak 21 ASWC Analog Steering Wheel Control 2 RSA Control Rear Seat Audio z 2 z z 2 2 Test Pin for manufacturing use only 5 3 E amp C I O x ean ja exam k e Joas p Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 13 49 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 XTA Family Radio Display Codes Radio Errors Radio receiver error codes when problems are detected relating to the Radio operation FAULT Radio mutes the outputs anytime the radio is ON until either the amplifier PIN 18 Cavity C2 senses either 5 Volts DC or an Open fault is displayed 1 If the AMPSENSE line is shorted to ground either at the Ra
29. eaning cassette into the tape player and play for 20 seconds engage the auto reverse feature and clean for another 20 seconds 3 Remove the cleaning cassette Now allow 2 3 minutes of drying time before proceeding Note It is recommended that the cleaning cassette is used every 15 hours of play time Replace cleaning cartridges when the felt pads look dirty Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 26 49 CD Player Error Messages HP Family Note The premium stereo receiver equipped with a CD player can identify and display the following error codes Error Message Cause Display Message Code No Type Description Optic focus error upside FOCUS a CD Focus down CD moisture etc ERROR 21 21 CD Tracking poss ol opic tracking control Mechanism unable to ERROR 22 22 CD Load Eject complete load unload within specified time frame There is a communication ERROR 23 23 CD Communication problem with the CD mechanism Error Messages XTA Family FOCUS Optics focus error or Disc is upside down in CD player LOAD Load Unload motor problem NO CD No CD inserted or Communication Problem TRACKING Optics loss of tracking control or Disc is upside down in CD Player CD Skips or Mutes e CD Changer Mounts Check for loose Stereo Receiver mounts Secure as necessary e Vibration Skip The CD player has been designed with a shock absorbing susp
30. ension much like that of a car Only under extreme operating temperatures and severe shock or vibration should the music be temporarily muted The temporary muting is considered normal and should not cause damage to the player or compact disc The player will resume normal playing when the vibration or shock subsides e Dew Point Operation Under certain cold temperature and humidity conditions moisture in the air will condense on the surrounding surfaces This most commonly occurs in the spring and fall when moisture accumulates on the windshield and body of the vehicle if it is left out at night The heart of the CD player is a laser lens assembly reading a shiny digital encoded disc If this lens or disc becomes fogged up with moisture the mechanism will have difficulty reading the disc and reproducing the music When this condition exist the player may intermittently mute This type of reaction is considered normal and will clear as soon as the CD or the player has warmed up enough to evaporate the moisture e Hot Operation Additional heat generated from the heater ducts during humid conditions when combined with that generated from the integral compact disc player can create temperatures in excess of normal operating conditions If the CD player encounters theses conditions it may produce distorted audio and temporarily mute These reactions are normal and if these conditions occur remove the CD until the operating temperature has returned to
31. ent being activated is direct switch activated or relay activated Check for switch pop If pop is still present install a second capacitor C2 as shown above Check for switch pop If pop still present install a third capacitor C3 as shown above Check for switch pop If pop still present install a feed through capacitor P N 176009 between the switch and The Delco Audio System Diagnostic Kit Kent Moore J39916A can be used to diagnose noise complaints See Diagnostic Test Kit page 48 W3003473 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 46 49 Antenna No AM Signal Weak FM Signal Usually symptoms of a broken center conductor of a lead in cable will result in no AM signal and weak FM signal Depending on the type antenna system used the lead in cable may be tested with an ohmmeter The multiplex antenna system with its electronic circuitry and no removable connection at the electronic module cannot be effectively tested Also due to the inaccessibility of the antenna end connection it may not be practical to test the lead in cables on ribbon and mast type systems If both ends of the lead in cable can be accessed the chart below can be used as a guide to determine if the lead in cable is OK When checking resistance cautiously wiggle the lead in tip and cable and watch for intermittent readings Note Zero the meter to avoid a false reading
32. er System 6 Speaker System Cavity Circuit Function Cavity Circuit Function 1 499RF RHS Dash 1 499RF RHS Dash Speaker Speaker 2 499LF LHS Dash 2 499LF LHS Dash Speaker Speaker 3 490 A 12 V Supply 3 490 A 12 V Supply Accessory Accessory 141R Dimmer Control 141R Dimmer Control 497R RHS Door 498RR RHS Rear Speaker Speakers 6 497L LHS Door 6 498LR LHS Rear Speaker Speakers 7 497L LHS Door 7 498LR LHS Rear Speakers Speaker 8 497R RHS Door 8 498RR RHS Rear Speaker Speakers 9 0C F Ground 9 0C F Ground 10 90A Light Control 10 90A Light Control 11 492 12 V Supply 11 492 12 V Supply Battery Battery 12 499LF LHS Dash 12 499LF LHS Dash Speaker Speaker 13 499RF RHS Dash 13 499RF RHS Dash Speaker Speaker Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 5 49 Note The following checks are valid for both non amplified and amplified sound systems However always check the amplifier system before replacing the stereo receiver Refer to Amplifier page 28 No Stereo Receiver Operation e Confirm no operation of receiver or playback devices If the receiver operates but the playback device does not refer to Cassette Tape Player page 24 or CD Player page 26 e Check for power supply Ignition key must be in ON or ACC position Back probe the wiring harness connector to the
33. he above test if no faults were found replace the stereo receiver Test operation after replacement 2See Harness Connectors page 4 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 7 49 No Stereo Receiver Display Illumination The stereo receiver display should illuminate when the ignition key is in the ON or ACC position Additionally the premium stereo receiver display should illuminate in the sleep mode e Check for power supply Ignition key must be in ON or ACC position Back probe the wiring harness connector to the stereo receiver Measuring Points Expected Value Pin 3 amp Alternate ground B If not correct check for blown fuse or damage incorrect truck wiring and take appropriate corrective action e Check for proper ground Ignition key must be in OFF position Back probe the wiring harness connector to the stereo receiver Measuring Points Expected Value Pin 9 Alternate ground less than 1 Q If not correct check damage incorrect truck wiring and take appropriate corrective action After performing the above test if no faults were found replace the stereo receiver There are no field replaceable lamps in the stereo receiver assembly Test operation after replacement No Stereo Receiver Face Illumination The stereo receiver face should illuminate when the headlight switch is on and also the display background light should au
34. nd Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 42 49 Conductive Shielding Tape Aluminum Tape P N 176005 This tape is used in the audio system to create a shield around a wiring harness in the vehicle or a component in the vehicle This tape will only suppress RFI conditions The tape must also be grounded using a braided ground strap to obtain optimum results see Braided Grounds page 41 Nickel Tape P N 176006 The purpose of this tape is to shield or suppress wiring harnesses and components from EMI RFI disturbances that affect the electrical functions in the vehicle The nickel tape is better able to shield magnetic interferences than aluminum tape However the nickel tape is very expensive compared to the aluminum tape 1 Conductive shielding tape 1 Conductive shielding tape 2 Antenna coaxial lead 2 Connect braided ground strap to a good chassis 3 In line connector ground 4 Connectground strap to a good chassis ground Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 43 49 Capacitors Capacitors are used to shunt AC noise to ground or to slow changes in voltage on a circuit Any capacitor that will be installed must be rated for 50 V operating voltage minimum The capacitor C should be placed as close to the noise as possible in order to be most effective W3003068 Capacitors are connected in parallel to a DC circuit because the capacitor will
35. nnections in noisy circuits Side Way Noise W3003059 1 Radio receiver 2 Speaker Side way noise is any noise that enters stereo receiver by a radiated field through the stereo receiver case Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 37 49 Possible Cause e Auxiliary electrical components monitors cell phones notebook computers etc e Noisy wiring or harness too close to the stereo receiver e Strong magnetic fields reaching the cassette tape player pickup head e High current wiring too close to the stereo receiver Troubleshooting Hints e f noise is present with the stereo receiver on but goes away when the receiver is moved out of its mounting location it is likely that sideway noise is the problem e Disconnect any auxiliary electrical components If noise goes away change the mounting location of the auxiliary electrical components and or of their wiring harness routing e Suppress or shield the noisy harness or wire or reroute it Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 38 49 Back Way Noise Back way noise is noise that enters the audio system through its wiring harness Back way noise is most commonly conducted through the power or ground circuits Some interference or noise is always present in the power and ground circuits When the unwanted signals overcome the ability of the audio system to suppress them they become
36. nts too close to the speaker or audio wires e Broken shorted or intermittent audio signal or speaker wires e Faulty shield wires Troubleshooting Hints e Noise induced into individual speakers is likely harness noise However if the noise is induced into harnesses between audio system components stereo receiver to amplifier etc all soeakers may be affected e Temporary speaker wires may be connected between the stereo receiver and noisy speaker to confirm harness noise entry e Check for improper component mounting or wire routing e Make sure all shield wiring is properly connected in mating connectors Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 40 49 Noise Sniffer Sniffer Construction The noise sniffer can be used along with the vehicle s radio to locate hot spots which are generating radio noise interference These hot spots will be found in the harnesses The sniffer can be made from an old piece of antenna lead in from a mast or power antenna The longer lead in the better since it will make the sniffer more flexible as a diagnostic tool W3003061 1 Center conductor wire 2 50mm 2 in of coax shield cut away 3 Antenna lead in with antenna base connector removed Construct sniffer per above graphic The 50 mm 2 in section with the outer coating and braided shield stripped back becomes the antenna when the sniffer is plugged into the radio s antenna socket It
37. onstructed to help isolate reception or noise problems To use the technician must gain access to the antenna input connection at the radio disconnect the vehicle antenna and connect the test antenna Connect the test antenna ground wire to a good vehicle ground If radio reception improves it is likely that the antenna mast or lead in is at fault see No AM Signal Weak FM Signal page 46 If radio noise improves the vehicle lead in cable may need to be moved away from electrically noisy devices see Noise Sniffer page 40 Note Do not hold the antenna mast by hand This will decrease the capability of the antenna to receive a station Test Antenna Construction A test antenna can be constructed from any old antenna lead in assembly Volvo antenna P N 1586621 and lead in base assembly P N 1082185 make an excellent test antenna due to convenient size of the antenna and a long lead in cable Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 47 49 W3003386 Fabricate a sheet metal plate per the drawing above Mount the plate on a 150 x 100 x 50 mm 6 x 4 x 2 in piece of wood Install the ground wire attach an alligator clip in the other end of the ground wire Install the antenna assembly 75 mm 3 in 100 mm 4 in Mounting holes 6 25 mm 1 4 in Ground wire hole 6 25 mm 1 4 in Antenna hole 18 75 mm 3 4 in O s W N W3003385 Volvo Trucks North America Inc Date Group No
38. ower Supply or Battery B on DIM Headlight switch must be ON Back probe the radio wiring harness connector with VOM set Ohms Measure between pin B 0 VDC variable with A6 DIM and A8 Ground Dimmer control Note If not correct check for blown fuse or damaged incorrect wiring and take the appropriate corrective action Page 22 49 Volvo Trucks North America Inc Date Group No Service Bulletin 4 2004 392 09 Steps to Verify USA Freguency 1 Turn vehicle ignition ON and radio OFF Radio displays current time 2 Press and hold DSPL TM SET button on radio until the hour digit on the time display begins flashing 3 Immediately press BAND button once If the radio displays USA DO NOT PRESS ANY BUTTONS UNTIL RADIO DISPLAY RETURNS TO CURRENT TIME Steps to Change Radio to USA Frequency 1 Turn vehicle ignition ON and Radio OFF Radio displays current time 2 Press and hold DSPL TM SET button on radio until the hour digit on the time display begins flashing 3 Press BAND button several times until the radio displays USA DO NOT PRESS ANY BUTTONS UNTIL RADIO DISPLAY RETURNS TO CURRENT TIME Page 23 49 Volvo Trucks North America Inc Service Bulletin Cassette Tape Player Date Group No Page 4 2004 392 09 24 49 Error Messages High Performance Family Note The premium stereo receiver equipped with a cassette player can identify and display the following error codes The basic ste
39. reo receiver does not have the ability to display error codes Error Message Cause Display Message Code No Type Description BAD TAPE 10 The player is unable to turn Tight Tape tape spindles and the tape is ejected BAD TAPE 11 The spindles of the tape are not turning proportionally and the tape is ejected Broken Tape ERROR 13 13 There is a communication Communication problem with the tape player The radio receiver displays error codes when problems are detected relating to the Tape Player operation BAD TAPE BAD TAPE conditions that are detected 3 Pinched tape roller NO TAPE No cassette tape inserted or Eject Audio Mute selected TP CLEAN Tape Cleaner Indicator Clean the tape 1 Cut tape player and then press and hold EJECT button until 2 Tape wound too tight CLN RST appears and then disappears Dirty Head For optimal audio performance the tape heads should be cleaned after every 15 hours of playback The cleaning should take place every 50 hours to prevent damage to the playback unit Symptoms of a dirty tape path include e Incorrect tape speed e Tape won t eject e Tape won t play in one direction e Muffled sound no high freguency response e Leftorright channel dead or plays at a lower volume e Tape deck eats tape Use a cleaning kit to clean the tape head The Diagnostic Test Kit Kent More J39916 A contains a tape head cleaning kit
40. rtionately with volume Pin F15 amp F16 AC voltage changing proportionately with volume Pin F4 amp F5 AC voltage changing proportionately with volume Pin F6 amp F7 AC voltage changing proportionately with volume See Harness Connectors page 28 If not correct check the radio receiver outputs and wiring harness If correct check speakers and wiring harness If all are correct replace the amplifier Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 34 49 Speakers No Sound From Speaker With the speaker removed from its mounting location and wiring harness disconnected the following checks can be performed e Visually inspect for obvious damage such as a torn cone or wiring from the connector to the voice coil broken e With a multimeter Kent More J39200 check the resistance value of the speaker The specified resistance value should be printed on the speaker generally 2 4 6 8 or 10 2 ohms The speaker may be tested with a 1 5 volt flashlight battery by connecting one speaker terminal to the battery negative post and momentarily touching the other speaker terminal to the positive post The speaker should produce a pop when connected If the speaker contains a capacitor it will only pop once Do not leave the battery connected With the speaker removed from its mounting location and wiring harness connected th
41. see Diagnostic Test Kit Cassette Head Cleaning page 25 A cleaning kit will generally contain e Tape head cleaner e Cleaning solvent e Extra cleaning pads Internal Faults If the radio on the stereo receiver works properly but the cassette tape player does not there is likely an internal fault in the cassette tape player There are no field repairs available for the cassette tape player Replace if necessary Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 25 49 Diagnostic Test Kit The Delco Audio System Diagnostic Kit Kent Moore J39916A can be used to diagnose cassette player complaints See Diagnostic Test Kit page 48 Diagnostic Test Kit Cassette Head Cleaning Note The audio system s equipped with a Bad Tape detector which must be turned off when cleaning the cassette player Inspection of the player must take place before using the cleaning and diagnostic cassette Using a light source carry out a visual check through the cassette entry flap and ensure that there is no debris inside the player and that the tape is not wrapped around the capstan Before proceeding with the diagnostic cassette the tone head pinch wheel s and capstan s must be cleaned To do this use the head cleaning cassette as follows 1 Auto reverse tape drive 2 Tape head 3 Capstan 4 Pinch roller 1 Put two drops of the cleaning solution on each felt pad w3003505 2 Insertthe cl
42. stereo receiver Measuring Points Expected Value Pin 3 amp Alternate ground B If not correct check for blown fuse or damage incorrect truck wiring and take appropriate corrective action e Check for proper ground Ignition must be in OFF position Back probe the wiring harness connector to the stereo receiver Measuring Points Expected Value Pin 9 Alternate ground less than 1 Q If not correct check for damage incorrect truck wiring and take appropriate corrective action e Check speaker outputs from the receiver Ignition must be in ON or ACC position Back probe the wiring harness connector to the stereo receiver Measuring Points Expected Value Pin 1 amp Pin 13 AC voltage changing proportionately with volume Pin 2 amp Pin 12 AC voltage changing proportionately with volume Pin 8 Pin 5 AC voltage changing proportionately with volume Pin 6 amp Pin 7 AC voltage changing proportionately with volume If correct check speakers or wiring harness After performing the above tests if no faults were found replace the stereo receiver Test operation after replacement See Harness Connectors page 4 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 6 49 The Receiver Will Not Maintain Pre Sets e The stereo receiver should maintain preset stations and the time even with the ignition key in the OFF posi
43. te check the radio receiver harness or speakers Measure between pin B1 RR Speaker and B2 RR Speaker Measure between pin B1 RR Speaker and A8 Ground Measure between pin B2 RR Speaker and A8 Ground Measure between pin B3 RF Speaker and B4 RF Speaker Measure between pin B3 RR Speaker and A8 Ground Measure between pin B4 RR Speaker and A8 Ground Measure between pin B5 LF Speaker and B6 LF Speaker Measure between pin B5 RR Speaker and A8 Ground Measure between pin B6 RR Speaker and A8 Ground Measure between pin B7 LR Speaker and B8 LR Speaker Measure between pin B7 RR Speaker and A8 Ground Measure between pin B8 RR Speaker and A8 Ground Note If the outputs are not correct check for speakers and the wiring harness that is shorted to the ground or battery Note If the outputs are correct replace the radio receiver Test the radio receiver operation after replacement Date Group No 4204 392 09 Page 19 49 AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to 8 VDC 1 2 B 5 25 to 8 VDC AC Voltage changing proportionally with Volume and Music 1 2 B 5 25 to
44. tion If the preset stations are not maintained check the constant power source and ground Ignition key must be in OFF position Back probe the wiring harness connector to the stereo receiver M ring Points E Val pasting reins xpected valle If not correct check for blown fuse or damage incorrect Pin 11 gt Alternate ground B truck wiring and take appropriate corrective action Pin 9 Alternate ground less than 1 Q After performing the above test if no faults were found replace the stereo receiver Test operation after replacement No Sound From Some Speakers Note If equipped with an amplifier only the upper two rear bunk speakers will play in the sleep mode Also if there is a failure in the power supply or the ground of the amplifier only the upper two rear bunk speakers will play e Check for AC voltage at suspect speakers see Speakers page 34 e Check speaker outputs from the stereo receiver Ignition key must be in ON or ACC position Back probe the wiring harness connector to the stereo receiver Measuring Points Expected Value Pin 1 amp Pin 13 AC voltage changing proportionately with volume Pin 2 amp Pin 12 AC voltage changing proportionately with volume Pin 8 amp Pin 5 AC voltage changing proportionately with volume Pin 6 amp Pin 7 AC voltage changing proportionately with volume If correct check speakers or wiring harness After performing t
45. tomatically dim to reduce glare The dimmer switch should raise and lower the brightness of the face illumination and the display background light e Check for power supply Headlight switch must be on Back probe the wiring harness connector to the stereo receiver 3 V l Measuring Points Expected Value If not correct check for blown fuse or damage incorrect Pin 4 gt Alternate ground B to O volts variable truck wiring and take appropriate corrective action with dimmer control 3See Harness Connectors page 4 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 8 49 e Check for proper ground Ignition key must be in OFF position Back probe the wiring harness connector to the stereo receiver Measuring Points Expected Value Pin 9 Alternate ground less than 1 Q If not correct check damage incorrect truck wiring and take appropriate corrective action After performing the above test if no faults were found replace the stereo receiver There are no field replaceable lamps in the stereo receiver assembly Test operation after replacement 4See Harness Connectors page 4 Volvo Trucks North America Inc Date Group No Page Service Bulletin 4 2004 392 09 9 49 Receiver Diagnostics Basic Sound System N C Dim 5 0 Ee lo RR Speaker AR Spat AF peat AF Seater iF Spat Spee TA paa TR Spent ee 3 E J s
46. und different The three basic tones used to test and evaluate base level speakers or other complex speaker systems are a bass 50 Hz sine tone a mid 500 Hz warble tone and a tweeter 9 000 Hz spectral tone The combination tone is a blend of the above three tones Bass Speaker Test The 50 Hz tone is used to evaluate the bass response of an audio system This tone is also helpful in evaluating audio systems witch have separate subwoofer amplifiers and speakers Mid Range Speaker Test The 500 Hz warble tone is used for the evaluation of range speaker response This tone is qualified as a warble tone because it has different audio characteristics than a sine tone This tone produces a warble sound At these mid range frequencies it is better to use a warble tone than a sine wave because the location of warble tone source such as a speaker is easier to identify A normal sine tone can set up a standing wave within a vehicle which can make it difficult to determine its source location Volvo Trucks North America Inc Date Group No Page Service Bulletin 4204 392 09 49 49 Tweeter Test The 9 000 Hz spectral tone is used for tweeter or high freguency evaluation This tone sounds like a group of crickets chirping This type of tone is used for two reasons one much like the warble tone to locate its source and two this type of tone is easier to identify for those people with high end hearing loss problems All Speaker Test With
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