No Response From BCM (Body Control Module)

NO RESPONSE FROM BCM (BODY CONTROL MODULE)





For a complete wiring diagram, refer to the Wiring Information.






1. 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. 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.

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. Body Verification Test.

No

- Go To 2

2. CHECK THE (A903), (A904), (A905) AND (A906) FUSED B(+) CIRCUITS FOR AN OPEN OR SHORT CIRCUIT




1. Turn the ignition off.
2. Disconnect the BCM B and C harness connectors.
3. Using a 12-volt test light connected to ground, check each Fused B(+) circuit.

Does the test light illuminate brightly for each circuit?

Yes

- Go To 3

No

- Repair the open or short in the (A903), (A904), (A905) or (A906) Fused B(+) circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK THE (Z922) GROUND CIRCUIT FOR AN OPEN




1. Using a 12-volt test light connected to 12-volts, check the (Z922) Ground circuits.

Does the test light illuminate brightly for each circuit?

Yes

- Go To 4

No

- Repair the open in the (Z922) Ground circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. CHECK THE (D65) AND (D64) CAN C BUS (+) CIRCUITS FOR AN OPEN




1. Turn the ignition off.
2. Disconnect the Rear CAN C Star Connector C2 harness connector.
3. Measure the resistance of the (D65) CAN C Bus (+) circuit between the Rear CAN C Star Connector C2 harness connector and the BCM E harness connector.
4. Measure the resistance of the (D64) CAN C Bus (-) circuit between the Rear CAN C Star Connector C2 harness connector and the BCM E harness connector.

Are the resistances below 5.0 Ohms?

Yes

- Replace the BCM. Body Control Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the open in the (D65) CAN C Bus (+) or (D64) CAN C Bus (-) circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.