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Audio System: Other Honda S2000 AP1

Entertainment Systems 21 illustrations ~4278 words

Audio Unit Connector Inputs and Outputs

When replacing an audio unit connector, match the wires to the cavities listed in the following table.

Scheme 11

Scheme 11: Audio Unit Connector Inputs and Outputs
Scheme 11: Audio Unit Connector Inputs and Outputs

Audio unit 20P connector

CavityWireConnects to
1YEL/GRNAM/FM antenna amplifier
2WHT/REDACC (Main stereo power supply)
3GRN/REDAudio remote switch
5 (2)RED/YELDriver's rear right speaker (+), Passenger's rear right speaker (+)
6 (2)BLU/YELDriver's rear left speaker (+), Passenger's rear left speaker (+)
7GRN/BLKPassenger's door speaker (+), Right tweeter (+) (1)
8GRN/YELDriver's door speaker (+), Left tweeter (+) (1)
9RED/BLKLights-on signal
10WHT/BLUConstant power
14YEL/BLUAudio remote switch (MUTE)
15 (2)BRN/WHTDriver's rear right speaker (-), Passenger's rear right speaker (-)
16 (2)GRY/REDDriver's rear left speaker (-), Passenger's rear left speaker (-)
17LT GRNPassenger's door speaker (-), Right tweeter (-) (1)
18GRY/REDDriver's door speaker (-), Left tweeter (-) (1)
19 (1)REDDash lights brightness controller
20BLKGround (G502)
(1) '02-09 models (2) '06-09 models
(1)'02-09 models
(2)'06-09 models

AUDIO UNIT 20P CONNECTOR REFERENCE

Note. All items may not apply to this vehicle. See the owner's manual for more information.

Audio Glossary

ItemDefinition
Active noise cancellationThe active noise cancellation system cancels some of the vehicle noise. This occurs in the 1,500-2,400 rpm range. Microphones detect the low frequency sound, and the system outputs a canceling sound from the audio speaker.
AM (Amplitude Modulation)The type of transmission used in the standard radio broadcast band from 530 to 1710 kHz.
AmplifierA device that increases the level of a signal by increasing the current or voltage.
AntennaA device used to send or receive electromagnetic waves through the air.
ATA (PC Card)A type of card that has been tested for use in playing WMA, and MP3 music files in the PC Card slot. Sizes of up to 1 GB have been tested.
Audio remote switchThe switches on the steering wheel that control the audio system.
Auxiliary jackAllows the customer to use a portable audio device to input audio recordings.
BalanceA control that changes the relative volume of the left and right channels.
BandA range of frequencies between two definite limits. Bands are assigned by the Federal Communications Commission for specific uses.
BassAn adjustment for the low frequency sounds of around 160 Hz and below.
ByteA unit of storage for computer files and memory. A CD holds approximately 700 million bytes.
CassetteAudio or video magnetic tape container having two reels. Customers can insert it for play back
Compact flashA standard for small-size (3x4 cm), memory cards used in mobile computers, PDAs, digital cameras. Compact flash memory cards are available in size of 32 MB up to 4 GB or more and can be played in the audio PC slot. Sizes above 1 GB have not been tested.
CD (Compact Disc)A 4.5-inch plastic disc containing digital audio recording that is played optically on a laser equipped player. Never use discs with a paper label. In a hot vehicle, labels can curl up and jam the unit.
CD (audio disc) changerCD player that can store and play more than one CD. Two types are available. Some units accept CDs fed into the changer one at a time, and others accept a magazine (with CDs stacked in a container).
CD playerA component designed to play compact disc recordings using a laser optical pickup. The signal from a CD player usually requires amplification.
Decibels (db)A method of measuring sound or radio signal strength received by the audio unit antenna.
DistortionInexact reproduction of an audio signal caused by playing music at levels the audio system cannot handle.
Dolby (noise reduction)A processing system developed by Dolby Laboratories that reduces the background noise on recording media. The result is a cleaner playback from the audio system.
DUETA serial data communication line used for sub display.
DVD (Digital Versatile Disc)A 4.5-inch CD-like format used for storing movies with digital audio and video features. The DVD-A format is a DVD format designed for DVD audio systems. Some vehicles can play DVD and DVD-A formats.
EqualizerA device that changes the relative volume of individual frequency bands to suit personal tastes of the listener.
FaderThe control that adjusts the relative volume levels of front and rear speakers in a four-speaker system.
FormatTo prepare a PC Card to receive files this function is done on a PC. Always choose either FAT or FAT32, as the NTFS format is not accepted by the system. Pick the default sectors for the format method selected.
FM (Frequency Modulation)The form of modulation used for radio and television sound transmission in most of the world. Less prone to interference than AM. The FM broadcast band in North America covers roughly 87.7 to 107.9 MHz.
GA-NetThe GA-Net allows the audio unit to communicate with all the audio and navigation components in a vehicle. If there is an open in the GA-Net or components, the entire audio and navigation system may appear inoperative.
GB (Gigabyte)A unit of memory or disk storage equal to one billion bytes (1000 million bytes).
HDDAbbreviation for hard disc drive. They are sensitive to heat and it is not recommended that they be used in the PC card slot for playing audio files.
Hertz (Hz)The unit of frequency equal to one cycle per second (cps). One kilohertz (kHz) equals 1,000 cps; one megahertz (MHz) equals 1 million cps.
Integrated amplifierA component that combines a pre amp and a power amp into a single unit. A receiver combines an integrated amp and a tuner into a single unit.
Jewel caseThe hard plastic case that contains a compact disc or DVD. Always use a jewel case to prevent scratches on the underside of a CD or DVD.
LCD (Liquid Crystal Display)A type of digital display that changes reflectance or transmittance when an electrical field is applied to it.
MemoryCircuitry or devices that hold information in electrical or magnetic form, such as the AM/FM radio presets.
MB (Megabyte)One million bytes. Written as 1 MB. Megabytes are used as a measure of digital storage space. For example, a CD can hold 650 MB.
MicAn abbreviation for microphone. For vehicles with navigation, the microphone accepts navigation voice commands to control audio and navigation functions.
MP3 music filesMP3 is an audio coding format. MP3 is a popular audio compression format on the Internet and computers. CDs and PC Cards with these files can be played on some vehicle's audio system.
MuteWhen the navigation gives guidance, the front speakers are muted (no music). When you use the voice control system, all of the speakers are muted.
NoiseUnwanted random sounds like buzzing, hiss, pops, static, whine, etc.
PC cardThe slot used for playing MP3 and WMA music files. The PC Card is usually a combination of a small flash card in a PCMCIA adaptor that slides into the slot. The ATA, SD, and compact flash types of cards have been tested up to 1 GB.
PCMCIAA computer standard for the slot that the PC card slides into. Another term for the PC card slot.
ProcessorThe part of an audio device that performs tasks/calculations. In the audio unit, the processor handles muting to allow the navi to speak its voice commands, and the decoding/playback of the sound files etc.
RadioA head unit that combines a tuner, a preamplifier, and often a power-amplifier.
Route guidance (RG)Spoken voice used for turn-by-turn navigation from the audio speakers.
SCF (Cold Start Fix) screensThese screens are displayed if the system requires a GPS initialization. The vehicle should be moved outside into an open area away from buildings/power lines.
StereoA recording of at least two channels where you can hear sound or music from the left or right side.
SD (Secure Digital) cardThis compact type of memory card allows for fast data transfer and has built-in security functions. SD cards have a small write-protection switch on the side.
ShieldA metallic foil or braided wire layer surrounding conductors which are designed to prevent electrostatic or electromagnetic interference (noise) from external sources such as buzzing, or popping sounds heard on the speakers.
Speaker (Loudspeaker)A device that converts electrical energy into acoustical energy (sound).
Speed-sensitive volume compensation (SVC)The SVC increases the audio volume to compensate for increased interior noise when the vehicle drivers at freeway speeds.
SubwooferA loudspeaker made to reproduce the lowest audio frequencies, about 25 Hz to 125 Hz.
TrackA sound recording on a CD, tape, or PC Card.
TrebleAn adjustment to control the volume of the high frequency sounds.
TunerA component (or part of a component) that receives radio signals and selects one broadcast from many.
TweeterA speaker designed to reproduce the higher frequencies (treble) only.
USBUniversal Serial Bus. The USB is used for playing the compressed audio files (MP3, WMA, and AAC) on an external device through the audio unit.
Voice coilA coil of wire wrapped around a tube and then attached to the speaker cone or diaphragm. When an audio signal is applied, the coil becomes an electromagnet and interacts with the permanent magnet causing the come or diaphragm to vibrate. We interpret these vibrations as sound.
Volume controlAllows you to control the loudness of the music.
WMA music fileWindows Media Audio File. This is an accepted format for music files to be played on either a CD-R, a CD-RW or a PC Card.
WooferA speaker that is designed to reproduce low (bass) frequencies only.
XM radioSatellite based radio transmission, which also uses a ground based repeater network to ensure seamless reception. The channels originate from XM's broadcast center, in Washington, DC, and uplink to two satellites. These satellites transmit the signal across the entire continental United States.
XM receiverThe external component that receives and processes the XM signals from the XM satellites, and terrestrial (land) stations. The audio unit communicates to the XM receiver over the GA-Net bus.

AUDIO GLOSSARY CHART

Scheme 12

Scheme 12: Circuit Diagram
Scheme 12: Circuit Diagram

Scheme 13

Scheme 13
Scheme 13

How to Obtain the Audio Unit Serial Number

Note. You can only do this procedure when the battery power has been disconnected from the audio unit and the audio unit displays CODE when the radio is turned on.

Scheme 14

Scheme 14: How to Obtain the Audio Unit Serial Number
Scheme 14: How to Obtain the Audio Unit Serial Number

Scheme 15

Scheme 15
Scheme 15
  1. Turn the ignition switch to ON (II).
  2. Make sure the audio system is turned off.
  3. Push and hold the preset No. 1 (A) and No. 6 (B) buttons.
  4. While holding the buttons, push the VOL PUSH PWR knob (C) to ON.
  5. Release the buttons and the self-diagnosis begins.
  6. The audio unit displays a U and a 4 digit number (A) (example U1234). These are the first 4 digits of the serial number. The display then changes to a L and a 4 digit number (B) (example L5678). These are the last 4 digits of the serial number.
  7. Use all 8 numbers as the serial number when using the Interactive Network ( i N) to retrieve the 5 digit anti-theft code.
  8. To end the self-diagnostic function, turn the audio unit off, or turn the ignition switch to LOCK (0).

Poor AM or FM radio reception or interference

Note. Check the vehicle battery condition first. Check for aftermarket accessories. Check the connectors for poor connections or loose terminals. Check the radio reception in an open area. Poor reception/interference can be caused by the following

  1. The radio station is far away.
  2. Atmospheric conditions are unfavorable.
  3. Tail buildings, mountains, or high-voltage power lines are nearby.

Scheme 16

Scheme 16
Scheme 16

Scheme 17

Scheme 17
Scheme 17

Scheme 18

Scheme 18
Scheme 18

Scheme 19

Scheme 19
Scheme 19

Scheme 20

Scheme 20
Scheme 20
  1. Turn the ignition switch to ON (II).
  2. Do the seek stop test (see «SEEK STOP TEST»(ref-351956-S25072752302009122900000) ). Is the number of stations the same or within 10 % of the known-good vehicle? YES -Multipath interference or weak station. Operation is normal. NO -Go to step 3.
  3. Check if the radio reception/interference is the same in several locations. Is the reception/interference the same as a known-good vehicle in several different locations? YES -Go to step 4. NO -Multipath interference or weak station. Operation is normal.
  4. Start the engine.
  5. Check the reception/interference while the engine is running. Is there noise (static or whine) only with the engine running? YES -Check all of the AM/FM antenna connections and the AM/FM antenna and radio grounds. If OK, check the charging system and the ignition system. NO -Go to step 6.
  6. Turn the ignition switch to LOCK (0).
  7. Check the antenna mast for cracks, or other damage. Make sure that the AM/FM antenna mast isn't loose. NOTE: Do not use any tools to tighten the antenna mast. Is there any damage? YES -Replace the AM/FM antenna mast (see «AM/FM ANTENNA REPLACEMENT»(ref-351956-S38641610122009122900000) ). NO -Go to step 8.
  8. Turn the ignition switch to ON (II).
  9. Turn on the audio unit.
  10. Measure the voltage between AM/FM antenna 2P connector terminal No. 2 and body ground. Is there battery voltage? YES -Go to step 11. NO -Go to step 18 .
  11. Turn the ignition switch to LOCK (0).
  12. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ), and disconnect the AM/FM antenna lead.
  13. Disconnect the AM/FM antenna lead from the AM/ FM antenna.
  14. Check for continuity between the AM/FM antenna lead center pin at the audio unit side and body ground. Is there continuity? YES -Replace the AM/FM antenna lead. NO -Go to step 15.
  15. Check for continuity between the AM/FM antenna lead center pin and the surface of the AM/FM antenna lead. Is there continuity? YES -Replace the AM/FM antenna lead. NO -Go to step 16.
  16. Check for continuity between the AM/FM antenna lead center pin at the audio unit side and the AM/ FM antenna lead center pin at the AM/FM antenna side. Is there continuity? YES -Go to step 17. NO -Replace the AM/FM antenna lead.
  17. Substitute a known-good AM/FM antenna lead, and check the radio reception. Is the reception normal? YES -Replace the AM/FM antenna lead. NO -Substitute a known-good audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ), and recheck. If the reception is still poor, replace the AM/FM antenna (see «AM/FM ANTENNA REPLACEMENT»(ref-351956-S38641610122009122900000) ).
  18. Turn the ignition switch to LOCK (0).
  19. Remove the audio unit, and disconnect the audio unit 20P connector. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism.
  20. Check for continuity between audio unit 20P connector terminal No. 1 and AM/FM antenna 2P connector terminal No. 2. Is there continuity? YES -Substitute a known-good audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ), and retest. NO -Repair open in the wire between the audio unit and the AM/FM antenna.

Audio unit power switch will not turn on (No information display and no sound)

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals.

Scheme 21

Scheme 21: Audio unit power switch will not turn on (No information display and no sound)
Scheme 21: Audio unit power switch will not turn on (No information display and no sound)

Scheme 22

Scheme 22
Scheme 22
  1. Turn the ignition switch to ON (II).
  2. Push the power switch ON to see if audio unit turns ON. Does the power turn ON? YES -Operation is normal. If the display turns ON, but no sound is heard or if the display does not turn ON, but the sound is OK. Go to audio system sound is weak or distorted (see «AUDIO SYSTEM SOUND IS WEAK OR DISTORTED (DISPLAY IS NORMAL)»(ref-351956-S08478844822009122900000) ), or no sound is heard from the speaker(s) (see «AUDIO UNIT POWER SWITCH WILL NOT TURN OFF»(ref-351956-S29686801232009122900000) ). NO -Go to step 3.
  3. Turn the ignition switch to LOCK (0).
  4. Check the No. 22 (15 A) fuse and the No. 9 (10 A) fuse in the under-dash fuse/relay box. Are the fuses OK? YES -Go to step 5. NO -Replace the fuse, and recheck.
  5. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ). Check that the audio unit connector is properly connected. Is it connected properly? YES -Go to step 6. NO -Reconnect the connector, and recheck the function.
  6. Disconnect the audio unit 20P connector. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism.
  7. Turn the ignition switch to ON (II).
  8. Measure the voltage between body ground and audio unit 20P connector terminals No. 2 and No. 10 individually. Is there battery voltage? YES -Go to step 9. NO -Repair open in the wire(s) between the No. 22 (15 A) fuse and the No. 9 (10 A) fuse in the under-dash fuse/relay box and the audio unit.
  9. Turn the ignition switch to LOCK (0).
  10. Reconnect the audio unit 20P connector.
  11. Turn the ignition switch to ON (II).
  12. Measure the voltage between audio unit 20P connector terminal No. 20 and body ground while pressing and releasing the audio unit power switch several times. Is there less than 0.1 V? YES -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ). NO -Repair open in the wire between the audio unit connector A (20P) terminal No. 20 and body ground (G502).

Audio unit power switch will not turn off

Note. Check for aftermarket accessories plugged into the vehicle accessory power sockets. Check the vehicle battery condition first.

Scheme 23

Scheme 23: Audio unit power switch will not turn off
Scheme 23: Audio unit power switch will not turn off
  1. Turn the ignition switch to ON (II).
  2. Push the power switch OFF or turn the ignition switch to LOCK (0) to see if the audio unit turns OFF. Is the audio unit OFF? YES -Operation is normal. NO -Go to step 3.
  3. Turn the ignition switch to LOCK (0).
  4. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ). Disconnect the audio unit 20P connector. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism.
  5. Measure the voltage between audio unit 20P connector terminal No. 2 and body ground. Is there battery voltage? YES -Check for short to power on the WHT/RED wire. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

No sound is heard from the speaker(s) (display is normal)

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals. Set the fader and balance positions to the center. Before doing symptom troubleshooting, check for power switch will not turn on troubleshooting (see AUDIO UNIT POWER SWITCH WILL NOT TURN ON (NO INFORMATION DISPLAY AND NO SOUND) ).

Scheme 24

Scheme 24: No sound is heard from the speaker(s) (display is normal)
Scheme 24: No sound is heard from the speaker(s) (display is normal)

Scheme 25

Scheme 25
Scheme 25
  1. Turn the ignition switch to ON (II).
  2. Turn on the audio unit and check that the volume button is not set to the MIN level. Is it at the MIN level? YES -Raise the volume level, and recheck the function. NO -Go to step 3.
  3. Check the MUTE mode. Is the MUTE mode set? YES -Cancel the MUTE mode by pressing the mute button, and recheck the function. NO -Go to step 4.
  4. Check to see if there is a specific speaker that has no sound. Is there a specific speaker? YES -Go to step 7 . NO -Go to step 5.
  5. Turn the ignition switch to LOCK (0).
  6. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ). Check that the audio unit connector is properly connected. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism. Is it connected properly? YES -Go to step 11 . NO -Reconnect the connector, and recheck the function.
  7. Turn the ignition switch to LOCK (0).
  8. Check the speaker with no sound for any damage. Is there any damage? YES -Substitute the speaker (see «Door Speaker Replacement»(ref-351956-S01290712972009122900000) ) and recheck. NO -Go to step 9.
  9. Remove the speaker(s) with no sound. Door speaker (see «Door Speaker Replacement»(ref-351956-S01290712972009122900000) ), Rear speaker (see «REAR SPEAKER REPLACEMENT»(ref-351956-S18158082052009122900000) ), Tweeter (see «Tweeter Replacement»(ref-351956-S04693515302009122900000) ), and disconnect its connector.
  10. Check the speaker connector for a loose or poor connection. Reconnect the speaker connector and recheck the symptom; does it still fail? YES -Go to step 11. NO -Operation is normal.
  11. Disconnect the speaker connector.
  12. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ), and disconnect the audio unit 20P connector. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism.
  13. Check for continuity between both pairs of speaker wires (+) and (-) at audio unit 20P connector. Then check each wire for continuity to body ground according to the table. SPEAKER TERMINAL CHART Speaker Terminal Wire color Driver's door speaker A8(+) GRN/YEL A18(-) GRN/RED Left tweeter A8(+) GRN/YEL A18(-) GRN/RED Front passenger's door speaker A7(+) GRN/BLK A17(-) LT GRN Right tweeter A7(+) GRN/BLK A17(-) LT GRN Left rear speaker A6(+) BLU/YEL A16(-) GRY/RED Right rear speaker A5(+) YEL A15(-) BRN/WHT Is there continuity? YES -Repair short in the wire(s) between the audio unit and the speaker(s). NO -Go to step 14.
  14. Connect each of the speaker connector terminals (+) and (-) with a jumper wire.
  15. Check for continuity between both pairs of speaker wires (+) and (-) at the audio unit 20P connector according to the table. SPEAKER TERMINAL CHART Speaker Terminal Wire color Driver's door speaker A8(+) GRN/YEL A18(-) GRN/RED Left tweeter A8(+) GRN/YEL A18(-) GRN/RED Front passenger's door speaker A7(+) GRN/BLK A17(-) LT GRN Right tweeter A7(+) GRN/BLK A17(-) LT GRN Left rear speaker A6(+) BLU/YEL A16(-) GRY/RED Right rear speaker A5(+) YEL A15(-) BRN/WHT Is there continuity? YES -Go to step 16. NO -Repair open in the wire(s) between the audio unit and the speaker(s).
  16. Substitute a known-good speaker(s) (see «Door Speaker Replacement»(ref-351956-S01290712972009122900000) ), and recheck the symptom. Does the symptom goes away? YES -Replace the faulty speaker(s). NO -Substitute a known-good audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ), and recheck. If the symptom/indication goes away, replace the original audio unit.

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals. Check for aftermarket accessories plugged into the vehicle accessory power sockets (including cell phones and cell phone chargers).

  1. Turn on the audio unit and check for sound in each mode (AM, FM, and CD). Is there sound from the speakers, and is the sound quality normal in each mode? YES -Intermittent failure. The system is OK at this time. Check for loose connections at the audio unit, and each speaker. NO -Speakers all work, sound quality is poor. If the sound is poor only with AM or FM, go to poor AM or FM radio reception or interference (see «SYMPTOM TROUBLESHOOTING»(ref-351956-S19539684602009122900000) ). If sound is poor in all modes, go to sound quality diagnosis (see «SOUND QUALITY DIAGNOSIS»(ref-351956-S05529040092009122900000) ).

Audio unit button illumination does not work

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals.

Scheme 26

Scheme 26: Audio unit button illumination does not work
Scheme 26: Audio unit button illumination does not work

Scheme 27

Scheme 27
Scheme 27

Scheme 28

Scheme 28
Scheme 28
  1. Turn the ignition switch to ON (II).
  2. Turn the headlight switch to the parking light position.
  3. Check the illumination of the audio unit buttons. Are the buttons illuminated? YES -Intermittent problem: the audio unit is OK at this time. Check for loose or poor connections at the audio unit 20P connector. NO -Go to step 4.
  4. Check the illumination of several other buttons not related to the audio system. Are the buttons illuminated? YES -Go to step 5. NO -Troubleshoot the interior lights.
  5. Turn the ignition switch to LOCK (0).
  6. Disconnect the audio unit 20P connector. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism.
  7. '00-03 models: Disconnect gauge assembly connector B(12P). '04-09 models: Disconnect gauge assembly connector A (22P).
  8. '00-03 models: Check for continuity between audio unit 20P connector terminal No. 19 and gauge assembly connector B (12P) terminal No. 10. '04-09 models: Check for continuity between audio unit connector A (20P) terminal No. 19 and gauge assembly connector A (22P) terminal No. 19. '00-03 models '04-09 models Is there continuity? YES -Go to step 9. NO -Repair open in the wire between the gauge assembly and the audio unit.
  9. Turn the ignition switch to ON (II).
  10. With the headlight switch still on, measure the voltage between audio unit 20P connector terminal No. 9 and body ground. Is there battery voltage? YES -Check the connections at the audio unit 20P connector. If all connections are OK, replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ). NO -Repair open in the wire between the under-dash fuse/relay box and the audio unit.

Radio preset memory is lost

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals.

Scheme 29

Scheme 29: Radio preset memory is lost
Scheme 29: Radio preset memory is lost
  1. Turn on the audio unit and set each of the radio station preset buttons. Does each button set properly? YES -Go to step 5 . NO -Go to step 2.
  2. Make sure the ignition switch is in LOCK (0).
  3. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).
  4. Measure the voltage between audio unit 20P connector terminal No. 10 and body ground. Is there battery voltage? YES -Go to step 5. YES -Repair open in the wire between the No. 22 (15 A) fuse and under-dash fuse/relay box and audio unit 20P connector terminal No. 10.
  5. Turn the ignition switch to LOCK (0) for 1 minute, then turn it back to ON (II).
  6. Test the preset buttons for proper recall operation. Do the preset buttons recall the set radio stations? YES -System is normal at this time. Check connections at the audio unit. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Audio disc does not eject

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals. Disc labels should not be used in the audio unit. They may damage the player mechanism.

  1. Turn on the audio unit. Does the system turn on? YES -Go to step 2. NO -Go to power switch will not turn on (see «AUDIO UNIT POWER SWITCH WILL NOT TURN ON (NO INFORMATION DISPLAY AND NO SOUND)»(ref-351956-S04528972332009122900000) ).
  2. Check to see if the disc ejects correctly with no binding by pushing the EJECT button. Is it normal? YES -Operation is normal. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Volume does not change

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals. Set the fader and balance positions to the center.

  1. Turn on the audio unit and listen to sound from the speakers. Is the sound normal? YES -Go to step 2. NO -Go to audio system sound is weak or distorted (see «AUDIO SYSTEM SOUND IS WEAK OR DISTORTED (DISPLAY IS NORMAL)»(ref-351956-S08478844822009122900000) ), or no sound is heard from speakers (see «AUDIO UNIT POWER SWITCH WILL NOT TURN OFF»(ref-351956-S29686801232009122900000) ).
  2. Operate the volume knob to see if the volume changes. Does the volume change? YES -Operation is normal. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Radio tuner does not change stations

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals.

  1. Turn on the audio unit and check the audio information on the display panel. Does the audio information display properly? YES -Go to step 2. NO -Go to power switch will not turn ON (see «AUDIO UNIT POWER SWITCH WILL NOT TURN ON (NO INFORMATION DISPLAY AND NO SOUND)»(ref-351956-S04528972332009122900000) ).
  2. Operate the tuning knob to see if the radio station changes. Does the radio station change? YES -Intermittent failure: the tuning knob is OK at this time. Check for loose or poor connections. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Audio disc does not load

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals. Disc labels should not be used in the audio unit. They may damage the player mechanism. Make sure the disc is compatible with the system (see the owner's manual for more information).

  1. Insert a known-good disc to see if the symptom can be duplicated. Does the disc load? YES -Operation is normal. If the disc loads normally, but will not play, go to audio disc does not play (see «AUDIO DISC DOES NOT PLAY»(ref-351956-S39549927662009122900000) ). NO -Go to step 2.
  2. Insert another disc. Does the disc load? YES -The original disc is faulty. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Special Tools Required

Diagnostics CD 07AAZ-SDBA100

Audio disc does not play

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals.

  1. Turn the ignition switch to ON (II).
  2. Try loading a disc. Does the disc load? YES -Go to step 3. NO -Go to audio disc does not load (see «Audio disc does not load»(ref-351956-S31662254732009122900000) ).
  3. Insert another disc to see if the symptom can be duplicated. Does the disc play? YES -Operation is normal. NO -Go to step 4.
  4. Insert audio diagnostic CD (T/N 07AAZ-SDBA100) in the audio unit. Does the disc play? YES -The original disc is faulty or has an unreadable format. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ). Special Tools Required Diagnostics CD 07AAZ-SDBA100 Skip test CD 07AAZ-SDBA200 or 07AAZ-SDBA300

Audio disc skips

  1. Confirm the vehicles tires are properly inflated.
  2. Check the customers CD for scratches, fingerprints, and marks. NOTE: The following test should be done with audio unit bass and treble set to customers listening performance. When comparing to known-good vehicles, the comparison should be done on same model and trim level.
  3. Test drive the vehicle to identify when customers CD skips. The audio diagnostic CD (T/N: 07AAZ-SDBA100) can be used if customers CD is not available. Use tracks 10 to 12. Does the disc skip? YES -Go to step 4. NO -Operation is normal.
  4. Compare the customers CD that is skipping to a known-good vehicle under the same conditions. Does the CD skip in the known-good vehicle under the same conditions? YES -Operation is normal. NO -Go to step 5. NOTE: The following test should be done with the vehicle parked and the engine running.
  5. Insert the diagnostic skip test CD (07AAZ-SDBA300). Play tracks 2 to 11 and note the track number(s) when the CD starts skipping. Do the same test on a known-good vehicle. Does the CD skip on same track number(s) as the known-good vehicle? YES -Operation is normal. NO -Go to step 6.
  6. Insert the diagnostic skip test CD (07AAZ-SDBA200). Play tracks 7 to 11 and tracks 13 to 15 and note the track number(s) when the CD starts skipping. Do the same test on a known-good vehicle. Does the CD skip on same track number (s) as known-good vehicle? YES -Operation is normal. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Audio remote switch does not work properly

Note. Check the vehicle battery condition first. Check the connectors for poor connections or loose terminals.

Scheme 30

Scheme 30: Audio remote switch does not work properly
Scheme 30: Audio remote switch does not work properly

Scheme 31

Scheme 31
Scheme 31
  1. Test the audio remote switch (see «AUDIO REMOTE SWITCH REPLACEMENT»(ref-351956-S37555081942009122900000) ). Is the audio remote switch OK? YES -Go to step 2. NO -Replace the remote switch (see «AUDIO REMOTE SWITCH REPLACEMENT»(ref-351956-S37555081942009122900000) ).
  2. Check the audio unit operation (volume, channel, and mode). Is the audio unit operation OK? YES -Go to step 3. NO -Substitute a known-good audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ), and recheck. If the problem goes away, replace the audio unit.
  3. Remove the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).
  4. Measure the resistance between audio unit 20P connector terminal No. 3 and audio remote switch 6P connector terminal No. 5 as specified in the table. AUDIO REMOTE SWITCH TABLE AUDIO REMOTE SWITCH REFERENCE Button held down VOL DOWN VOL UP CHANNEL UP MODE (No button pressed) Resistance about 512 ohms about 263 ohms about 1.1 Kohms about 2.5 Kohms about 10 Kohms Is the resistance OK? YES -Go to step 5. NO -Repair open or high resistance in the circuit between the audio unit and the audio remote switch. If the wires are OK, check audio remote switch ground (G501).
  5. Disconnect the audio unit 20P connector and audio remote switch 6P connector. NOTE: Eject the disc before removing the audio unit to prevent damaging the CD player's load mechanism.
  6. Check for continuity between audio unit 20P connector terminal No. 3 and body ground. Is there continuity? YES -Repair short to body ground in the wire between the audio unit and the audio remote switch. NO -Replace the audio unit (see «AUDIO UNIT REMOVAL/INSTALLATION»(ref-351956-S28419735862009122900000) ).

Left/Right Channel ID

Do this test to confirm proper channel routing.

  1. Insert audio diagnostic CD (T/N 07AAZ-SDBA100) into the CD player.
  2. Play track No. 1 (left, both, right channel ID) at a normal, or slightly higher than normal, volume level.
  3. The voice should be audible only from the channel or channels when indicated. If the channel ID is correct for each side, go to phase test. If the channel ID is not correct, check for: Shorted speaker wire Faulty audio unit Special Tools Required Diagnostics CD 07AAZ-SDBA100

Frequency sweep

Do this test to find rattles or reverberation that may cause a perception of poor sound quality.

  1. Insert audio diagnostic CD (T/N 07AAZ-SDBA100) into the CD player.
  2. Play track No. 13 (sweep from 500 Hz to 35 Hz) at a normal, or slightly higher than normal, volume level.
  3. Listen to each speaker for poor sound quality or vibrations caused by specific frequencies. Use the voice-over to estimate the frequency that causes the vibration. Use the audio unit's fader and balance settings to help isolate the channel with the problem. If vibrations or poor sound quality is heard, go to step 4. If no vibrations or poor sound quality is heard, go to sound judging (see «FREQUENCY SWEEP»(ref-351956-S12581862402009122900000) ).
  4. Choose the appropriate track from No. 14 to 25 (small range frequency sweep) or 26 to 53 (single frequencies) to recreate the frequency that caused the poor sound quality or vibration located in step 3: this aids in diagnosis of the cause. NOTE: When you get to the track that recreates the problem, select the repeat function on the audio unit; this will help you isolate the cause.
  5. Replace or insulate the source of the vibration or, if the speaker is the source of the poor sound quality, replace it.

Special Tools Required

Diagnostics CD 07AAZ-SDBA100

Sound judging

Do this test to compare overall sound quality, imaging, and dynamics between the customer's vehicle and a known-good vehicle. Only use a vehicle of the same model and trim level for this test.

  1. In the customer's vehicle, set the bass, treble, fader, and balance settings to the customer's normal settings that were written down before beginning testing.
  2. Insert audio diagnostic CD (T/N 07AAZ-SDBA100) into the CD player.
  3. Play tracks No. 7 to 12 (sound quality, midland, dynamics, and imaging demonstration tracks) at a normal, or slightly higher than normal, volume level. Write down the volume setting being used.
  4. Listen to areas of the track that stand out as being either very clear or poorer than other areas of the track.
  5. Insert audio diagnostic CD (T/N 07AAZ-SDBA100) into the CD player of a known-good vehicle.
  6. Play the tracks at the same volume level and the same bass, treble, balance, and fader settings as used in step 3 in the customer's vehicle.
  7. Listen to the same area of the track that stood out as being either very clear or poorer than other areas of the track.
  8. Compare the customer's vehicle's sound quality results to the known-good vehicle's results. If the sound quality in the customer's vehicle is comparable to the sound quality in the known-good vehicle, then the customer's vehicle is operating as designed. If the sound quality is not comparable, check these items in order. Loose or improperly installed speakers or other hardware that may become excited by the vibrations generated by the speakers Poor power or ground to the audio unit Damaged speaker(s) Faulty audio unit

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