Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. Turn the Park Lamps on.
3. With the scan tool, read the Body Control Module (BCM) DTCs and record on the repair order.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - 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. If no problems are found, test complete.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (L3) LICENSE PLATE LAMP CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the Park Lamps off.
2. Turn the ignition off.
3. Disconnect the License Plate Lamp harness connector.
4. Turn the ignition on.
5. Measure the voltage between ground and the (L3) License Plate Lamp Control circuit at the License Plate Lamp harness connector.
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage in the (L3) License Plate Lamp Driver circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (L3) LICENSE PLATE LAMP CONTROL CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the BCM C5/E harness connector.
3. Measure the resistance of the (L3) License Plate Lamp Control circuit between the License Plate Lamp harness connectors and the BCM C5/E harness connector.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open in the (L3) License Plate Lamp Control circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (Z922) GROUND CIRCUIT FOR AN OPEN
1. Check for continuity between ground and the (Z922) Ground circuit at the License Plate Lamp harness connector.
  Is there continuity between ground and the (Z922) Ground circuit?
  
  Yes
  - Repair the open in the (Z922) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK THE BCM FOR CORRECT OPERATION
1. Turn the ignition off.
2. Reconnect the BCM C5/E harness connector.
3. Turn the ignition on.
4. Turn the Park Lamps on.
  NOTE:
  The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery
5. Connect a 12-volt test light between the (L3) License Plate Lamp Control circuit and the (Z922) Ground circuit at the License Plate Lamp harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Replace the bulb or lamp causing the short to voltage or open in accordance with the Service Information. Refer to LAMP, LICENSE PLATE, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .