Rear Heater-A/C Control Power and Ground Circuits

Rear Heater-A/C Control Power and Ground Circuits Troubleshooting

1. Check the No. 3 (7.5 A) fuse in the driver's under-dash fuse/relay box.

Is the fuse OK?

YES - Go to step 2.

NO - Replace the fuse, and recheck.

2. Disconnect the rear heater-A/C control panel-unit 1 connector.
3. Turn the ignition switch ON (II).




4. Measure the voltage between the No. 14 terminal of the rear heater-A/C control panel-unit 14P connector and body ground.

Is there battery voltage?

YES - Go to step 5.

NO - Repair open in the wire between the No. 3 fuse in the driver's under-dash fuse/relay box and the rear heater-A/C control panel-unit.

5. Turn the ignition switch OFF.




6. Check for continuity between the No. 4 terminal of the rear heater-A/C control panel-unit 14P connector and body ground.

Is there continuity?

YES - Check for loose wires or poor connections at the rear heater-A/C control panel-unit 14P connector. If the connections are good, substitute a known-good rear heater-A/C control panel-unit, and recheck. If the symptom/indication goes away, replace the original rear heater-A/C control panel-unit.

NO - Check for an open in the wire between the rear heater-A/C control panel-unit and body ground. If the wire is OK, check for poor ground at G501.