Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. Turn the Park Lamps on.
3. With the scan tool, read DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Go To 2
  No
  - Test complete. The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (L77) LEFT FRONT PARK LAMP DRIVER CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS
1. Turn the Park Lamps off.
2. Turn the ignition off.
3. Disconnect the Left Front Lamp Assembly harness connector.
4. Disconnect the BCM A harness connector.
5. Turn the ignition on.
6. Measure the voltage between ground and the (L77) Left Front Park Lamp Driver circuit.
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage in the (L77) Left Front Park Lamp Driver circuit.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 3
CHECK THE (L77) LEFT FRONT PARK LAMP DRIVER CIRCUIT FOR AN OPEN IN THE HARNESS
1. Turn the ignition off.
2. Measure the resistance of the (L77) Left Front Park Lamp Driver circuit between the Left Front Lamp Assembly harness connector and the BCM A harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the open in the (L77) Left Front Park Lamp Driver circuit.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (Z901) GROUND CIRCUIT FOR AN OPEN IN THE HARNESS
1. Using a 12-volt test light connected to 12-volts, check the (Z901) Ground circuit.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 5
  No
  - Repair the open in the (Z901) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE BCM FOR CORRECT OPERATION
1. Turn the ignition off.
2. Reconnect the BCM A harness connector.
3. Connect a 12-volt test light between the (L77) Left Front Park Lamp Driver circuit and the (Z901) Ground circuit at the Left Front Lamp Assembly harness connector.
4. Turn the ignition on.
5. Turn the Park Lamps on.
  Does the test light illuminate brightly?
  
  Yes
  - Replace the Left Front Lamp Assembly in accordance with the Service Information. Refer to UNIT, FRONT LAMP, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Replace the BCM in accordance with the Service Information. Refer to MODULE, BODY CONTROL, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .