Diagnostic Test

CHECK IF THE DTC IS ACTIVE
1. Ignition on, engine running
2. With the scan tool, read Instrument Panel Cluster (IPC) DTCs.
3. Is this DTC active?
  
  Yes
  - Go To 2
  No
  - Go To 6
CHECK FOR BODY CONTROL MODULE (BCM) DTCS
1. With the scan tool, read Body Control Module (BCM) DTCs.
  Are there any dimmer DTCs set in the BCM?
  
  Yes
  - Refer to DIAGNOSIS AND TESTING and perform the appropriate diagnostic procedure.
  No
  - Go To 3
CHECK IF OTHER LIGHTS ARE DIMMING
1. While Monitoring other lights on the dimmer circuit, adjust the dimmer switch from high to low and back.
  NOTE:
  Depending on the vehicle options, this can include the cup holder, fuel door switch, media port and center console lamps.
  
  Are other lights working properly with the dimmer being adjusted?
  
  Yes
  - Go To 4
  No
  - Go To 5
CHECK THE (E12) PANEL LAMP DRIVER CIRCUIT FOR AN OPEN TO THE IPC
1. Turn the ignition off.
2. Disconnect the Headlamp Switch harness connector.
3. Disconnect the IPC harness connector.
4. Check the resistance of the (E12) Panel Lamps Driver circuit between the Headlamp Switch harness connector and the IPC harness connector.
  Is the resistance above 5.0 Ohms?
  
  Yes
  - Repair the (E12) Panel Lamps Driver circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Replace the Instrument Cluster in accordance with the Service Information. Refer to REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (E12) PANEL LAMP DRIVER CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the Headlamp Switch harness connector.
3. Disconnect the IPC harness connector.
4. Check the resistance of the (E12) Panel Lamps Driver circuit between the Headlamp Switch harness connector and the IPC harness connector.
  Is the resistance above 5.0 Ohms?
  
  Yes
  - Repair the (E12) Panel Lamps Driver circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Replace the Headlamp Dimmer Switch in accordance with the Service Information. Refer to SWITCH, DIMMER, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set the DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this module. Wiggle the wiring and connectors while checking for shorted and open circuits.
3. Check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. Check Service Bulletins for any possible causes that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Test complete.