Back Lighting Inoperative (ATC)

*BACK LIGHTING INOPERATIVE (ATC)

For a complete wiring diagram Consult Diagrams/Electrical





Diagnostic Test

1. CHECK FOR INSTRUMENT CLUSTER DTCs
Turn the ignition on.
With the scan tool, read Instrument Cluster DTCs.
Does the scan tool display any DTCs?

Yes

- Diagnose and repair the DTC(s).

No

- Go To 2

2. CHECK FOR BCM DTCs
With the scan tool, read BCM DTCs.
Does the scan tool display any DTCs?

Yes

- Diagnose and repair the DTC(s).

No

- Go To 3

3. CHECK (E12) PANEL LAMPS DRIVER CIRCUIT VOLTAGE
Turn the ignition off.
Rotate the Panel Lamps Dimmer switch to the off position.
Disconnect the A/C Heater Control harness connector.
Turn the park lamps on.
Measure the voltage of the (E12) Panel Lamps Driver circuit while rotating the Panel Lamps Dimmer switch from the off position to the full brightness position.
Does the voltage change from approximately 4.5 volts to 11.5 volts?

Yes

- Go To 4

No

- Go To 5

4. INSPECT INOPERATIVE BULB(S)
Remove the inoperative bulb(s) from the A/C Heater Control.
Inspect the inoperative bulb(s).
Is each inoperative bulb okay?

Yes

- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Replace the inoperative bulb(s).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

5. CHECK (E12) PANEL LAMPS DRIVER CIRCUIT FOR AN OPEN
Disconnect the Instrument Cluster C1 harness connector.
Measure the resistance of the (E12) Panel Lamps Driver circuit between the A/C Heater Control harness connector and the Instrument Cluster C1 harness connector.
Does the ohm meter read open circuit?

Yes

- Repair the (E12) Panel Lamps Driver circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Replace the Instrument Cluster.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.