Rear A/C-Heater Control Module Illumination Inoperative
Possible Causes:
- Check for HVAC DTCs.
- Inoperative Bulb.
- Fused Panel Lamp Dimmer Switch Signal circuit open.
- Rear A/C-Heater Control Module.
CAUTION:
Always turn ignition off before disconnecting or connecting any control module connector. Failure to do so could result in damage to control module.
NOTE:
Ensure vehicle being tested has a fully charged battery. If it does not, false symptoms may occur.
NOTE:
For component location, see appropriate illustration under COMPONENT LOCATIONS
. For terminal identification, see appropriate illustration under CONNECTOR IDENTIFICATION
. For circuit and wire color identification, see WIRING DIAGRAMS
. For component removal and installation procedures, see appropriate component under REMOVAL & INSTALLATION
.
Testing:
- Turn ignition off. Connect DRBIII(R) to DLC. Turn ignition on. Using DRBIII(R), read HVAC DTCs. Does DRBIII(R) display any HVAC DTCs? If yes, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go to next step.
- Remove the bulb from the Rear A/C-Heater Control Module. Measure the bulb's resistance. Is resistance less than 5 ohms? If yes, go to next step. If no, replace bulb. Perform BODY VERIFICATION TEST under VERIFICATION TESTS.
- Disconnect Rear A/C-Heater Control Module harness connector. Turn the Headlamp switch on. Rotate the Cargo Dome Switch to the full brightness setting. Measure voltage on Rear A/C-Heater Control Module harness connector terminal No. 1. Is voltage more than 4.9 volts? If yes, replace Rear A/C-Heater Control Module. Perform BODY VERIFICATION TEST under VERIFICATION TESTS. If no, repair open in Fused Panel Lamp Dimmer Switch Signal circuit. Perform BODY VERIFICATION TEST under VERIFICATION TESTS.