Operation CHARM: Car repair manuals for everyone.

Audio Communication Line Circuit Troubleshooting

Audio Communication Line Circuit Troubleshooting

1. Turn the ignition switch to LOCK (0).
2. Disconnect the climate control unit connector B (16P) and audio unit connector C (28P).
3. Check for continuity between the climate control unit connector B (16P) No. 11 terminal and the audio unit connector C (28P) No. 15 terminal.






Is there continuity?

YES - Go to step 4.

NO - Repair open in the wire between the climate control unit connector B (16P) and the audio unit connector C (28P).

4. Check for continuity between the body ground and the climate control unit connector B (16P) No. 11 terminal.






Is there continuity?

YES - Repair short to body ground in the wire between the climate control unit connector B (16P) and the audio unit connector C (28P).

NO - Go to step 5.

5. Reconnect the climate control unit connector B (16P).
6. Disconnect the in-car temperature sensor 2P connector.
7. Connect the climate control unit connector B (16P) No. 11 and No. 14 terminals with a jumper wire.






8. Turn the ignition switch ON (II).
9. Press and hold the DEF button and OFF button.

Is the DEF button LED blinking?

YES - Audio unit is faulty, replace the audio unit.

NO - Climate control unit is faulty, replace the climate control unit.