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 the passenger's climate control switch 12P connector No. 1 terminal.

Is there battery voltage?
YES - Go to step 7.

NO - Repair 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 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 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 the driver's climate control switch 16P connector No. 11 terminal.

Is there battery voltage?
YES - Go to step 18.

NO - Repair 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 the driver's climate control switch 16P connector No. 14 terminal.

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. Dashboard Wire Harness (View of Middle Section) Connector and Harness Locations






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

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

Is there continuity?
YES - Go to step 22.

NO - Repair open in the wire(s) between the driver's climate control switch and the climate control unit.






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

Is there continuity?
YES - Repair 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