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HVAC Communication Line Circuit Troubleshooting




HVAC Communication Line Circuit Troubleshooting

1. Disconnect climate control unit connector A (32P) and audio-navigation and HVAC switch panel connector B (32P) or audio and HVAC switch panel connector B (32P).

2. Check for continuity between the following terminals of climate control unit connector A (32P) and audio-navigation and HVAC switch panel connector B (32P) or audio and HVAC switch panel connector B (32P).









Is there continuity?

YES -

Go to step 3.

NO -

Repair an open in the wire between climate control unit connector A (32P) and audio-navigation and HVAC switch panel connector B (32P) or audio and HVAC switch panel connector B (32P).�

3. Check for continuity between body ground and climate control unit connector A (32P) terminals No. 3 and No. 4 individually.





Is there continuity?

YES -

Repair a short to body ground in the wire between climate control unit connector A (32P) and audio-navigation and HVAC switch panel connector B (32P) or audio and HVAC switch panel connector B (32P).�

NO -

Substitute a known-good audio-navigation and HVAC switch panel Audio-Navigation and HVAC Switch Panel Removal/Installation or the audio and HVAC switch panel Audio and HVAC Switch Panel Removal/Installation, and recheck. If the symptom goes away, replace the original audio-navigation and HVAC switch panel or the audio and HVAC switch panel. If the symptom still present, replace the climate control unit Service and Repair.�