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HVAC Communication Line Circuit Troubleshooting (Without Navigation)




HVAC Communication Line Circuit Troubleshooting

Without Navigation

1. Disconnect audio and HVAC switch panel connector A (20P).

2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

3. Measure the voltage between audio and HVAC switch panel connector A (20P) terminals No. 11 and body ground.





Is there any voltage?

YES -

GO to step 4.

NO -

Repair an open in the wire between the No. 16 (7.5 A) fuse in the driver's under-dash fuse/relay box and the audio and HVAC switch panel.

4. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

5. Disconnect climate control unit connector A (32P) and audio and HVAC switch panel connector B (32P).

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









Is there continuity?

YES -

Go to step 7.

NO -

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

7. 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 and HVAC switch panel connector B (32P).

NO -

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