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Audio Communication Line Circuit Troubleshooting

Audio Communication Line Circuit Troubleshooting

1. Turn the ignition switch to LOCK (0).
2. Disconnect climate control unit connector A (28P) and the audio-HVAC subdisplay or display unit 12P connector.
3. Check for continuity between the following terminals of climate control unit connector A (28P) and the audio-HVAC subdisplay or display unit 12P connector.






Is there continuity?

YES - Go to step 4.

NO - Repair open in the wire between climate control unit connector A (28P) and the audio-HVAC subdisplay or display unit 12P connector.

4. Check for continuity between body ground and climate control unit connector A (28P) No. 19 and No. 20 terminals individually.






Is there continuity?

YES - Repair short to body ground in the wire between climate control unit connector A (28P) and the audio-HVAC control unit 12P connector.

NO - Go to step 5.

5. Reconnect climate control unit connector A (28P).
6. Connect the audio-HVAC subdisplay or display unit 12P connector No. 7 and No. 8 terminals with a jumper wire.






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

Is the DEF button LED blinking?

YES - Audio-HVAC subdisplay unit or display unit is faulty, replace the audio-HVAC subdisplay unit or audio-HVAC display unit.

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