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Climate Control Switch Communication Line Circuit Troubleshooting




Climate Control Switch Communication Line Circuit Troubleshooting

1. Operate the climate control system with the passenger's climate control switch in all modes.

Does the climate control system operate?

YES -

Intermittent failure.

NO -

Go to step 2.

2. Operate the climate control system with the driver's climate control switch in all modes.

Does the climate control system operate?

YES -

Go to step 3.

NO -

Go to step 11.

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

4. Disconnect the passenger's climate control switch 12P connector.

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

6. Measure the voltage between body ground and passenger's climate control switch 12P connector terminal No. 12 .





Is there battery voltage?

YES -

Go to step 7.

NO -

Repair an open in the wire between the passenger's climate control switch and the No. 36 (10 A) fuse in the under-dash fuse/relay box. If wires are OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.

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

8. Disconnect the driver's climate control switch 16P connector.

9. Check for continuity between the passenger's climate control switch 12P connector and the driver's climate control switch 16P connector as shown.









Is there continuity?

YES -

Go to step 10.

NO -

Repair an open in the wires between the driver's climate control switch and the passenger's climate control switch.

10. Check for continuity between body ground and the passenger's climate control switch 12P connector terminals as shown.





Is there continuity?

YES -

Repair a short to body ground in the wire(s) between the driver's climate control switch and the passenger's climate control switch.

NO -

Substitute a known-good passenger's climate control switch, and recheck. If the symptom goes away, replace the original passenger's climate control switch Climate Control Switch Removal/Installation.

11. Press and hold the FAN UP switch, then press the OFF switch.

Is the REC button LED blinking?

YES -

Substitute a known-good driver's climate control switch, and recheck the function. If the symptom is still present, replace the climate control unit Climate Control Unit Removal/Installation.

NO -

Go to step 12.

12. Check the driver's climate control switch LEDs.

Are the REC button and AUTO button LEDs blinking?

YES -

Driver's climate control switch is faulty, replace the driver's climate control switch Climate Control Switch Removal/Installation.

NO -

Go to step 13.

13. Check the driver's climate control switch LEDs.

Are the REC button and DUAL button LEDs blinking?

YES -

Substitute a known-good driver's climate control switch, and recheck the function. If the symptom is still present, replace the climate control unit Climate Control Unit Removal/Installation.

NO -

Go to step 14.

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

15. Disconnect the driver's climate control switch 16P connector.

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

17. Measure the voltage between body ground and driver's climate control switch 16P connector terminal No. 9.





Is there battery voltage?

YES -

Go to step 18.

NO -

Repair an open in the wire between the driver's climate control switch and the No. 36 (10 A) fuse in the under-dash fuse/relay box. If wires are OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.

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

19. Check for continuity between body ground and driver's climate control switch 16P connector terminal No. 14.





Is there continuity?

YES -

Go to step 20.

NO -

Check for an open in the wire between the driver's climate control switch and body ground. If the wire is OK, check for poor ground at G502.

20. Disconnect climate control unit connector B (16P).

21. Check for continuity between climate control unit connector B (16P) terminal No. 6 and driver's climate control switch 16P connector terminal No. 13 .





Is there continuity?

YES -

Go to step 22.

NO -

Repair an open in the wire between the driver's climate control switch and the climate control unit.

22. Check for continuity between driver's climate control switch 16P terminals No. 13 and No. 14 .





Is there continuity?

YES -

Repair a short to another wire.

NO -

Substitute a known-good driver's climate control switch, and recheck. If the symptom is still present, replace the climate control unit Climate Control Unit Removal/Installation.