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Navigation Communication Line Circuit Troubleshooting




Navigation Communication Line Circuit Troubleshooting

1. Operate the climate control system in several modes.

Is the climate control system OK?

YES -

Go to step 2.

NO -

Do the Self-Diagnostic Function with the HDS or the climate control unit.

2. Do the system links.

Is the A/C or Mic icon red?

YES -

- If A/C icon is red, go to step 3.
- If Mic icon is red, go to "voice control does not work/respond" in the navigation system symptom troubleshooting Symptom Troubleshooting.

NO -

Go to step 8.

3. Turn the ignition switch to LOCK (0).

4. Disconnect audio-navigation unit connector D (20P).

5. Disconnect climate control unit connector B (12P).

6. Check for continuity between the following terminals of climate control unit connector B (12P) and audio-navigation unit connector D (20P).









Is there continuity?

YES -

Go to step 7.

NO -

Repair an open in the wire(s) between the climate control unit and the audio-navigation unit.

7. Check for continuity between body ground and climate control unit connector B (12P) terminals No. 7, No. 8, and No. 9 individually.





Is there continuity?

YES -

Repair a short to body ground in the wire(s) between the climate control unit and the audio-navigation unit.

NO -

Reconnect the climate control unit connector B (12P), then go to step 9.

8. Turn the ignition switch to LOCK (0).

9. Connect the audio-navigation unit connector D (20P) terminals No. 4, No. 5, and No. 14 with jumper wires.





10. Turn the ignition switch to ON (II).

11. Press and hold the AUTO and ON/OFF buttons, then turn the ignition switch to ON (II).

12. Check the mode indicator displaying in the audio-navigation switch panel display.





Is the HEAT/VENT indicator solid with the remaining icons blinking?

YES -

Substitute a known-good audio-navigation unit (including the HDD), and recheck. If the symptom goes away, replace the audio-navigation unit Audio-Navigation Unit Removal/Installation.

NO -

Substitute a known-good climate control unit, and recheck. If the symptom goes away, replace the original climate control unit Climate Control Unit Removal/Installation.