Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

TEST FOR INTERMITTENT CONDITION
NOTE:
If the scan tool is unable to identify the vehicle, a CAN C bus concern may be present. Perform the CAN C BUS NO RESPONSE diagnostic procedure. Refer to CAN C BUS NO RESPONSE .

NOTE:
Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.
1. Turn the ignition on.
  NOTE:
  Make sure the battery voltage is between 10.0 and 16.0 volts.
2. With the scan tool, read the module status.
  NOTE:
  Check the BCM for any active CAN hardware DTCs, perform DTC before proceeding. Refer to the DTC INDEX article.
  
  Does the scan tool indicate that the module is active on the bus?
  
  Yes
  - The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 2
CHECK THE (A101) FUSED B(+) CIRCUIT FOR AN OPEN OR SHORT CIRCUIT
1. Turn the ignition off.
2. Disconnect the BCM C7 harness connector.
3. Using a 12-volt test light connected to ground, check the Fused B(+) circuit.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 3
  No
  - Repair the open or short in the (A101) Fused B(+) circuit.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (Z921) GROUND CIRCUIT FOR AN OPEN
1. Disconnect the BCM C8 harness connector.
2. Using a 12-volt test light connected to 12-volts, check the (Z921) Ground circuits.
  Does the test light illuminate brightly for each circuit?
  
  Yes
  - Go To 4
  No
  - Repair the open in the (Z921) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (D65) AND (D64) CAN C BUS (+) CIRCUITS FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the BCM C4 harness connector.
3. Measure the resistance of the (D65) CAN C Bus (+) circuit between the DLC harness connector and the BCM C4 harness connector.
4. Measure the resistance of the (D64) CAN C Bus (-) circuit between the DLC harness connector and the BCM C4 harness connector.
  Are the resistances below 5.0 Ohms?
  
  Yes
  - Replace the BCM in accordance with the Service Information. Refer to MODULE, BODY CONTROL, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Repair the open in the (D65) CAN C Bus (+) or (D64) CAN C Bus (-) circuit.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .