1000 - 1999: 1021

1021-00 NO COMMUNICATION WITH BCM AND CENTRAL LOCKING PUMP/SECURITY SYSTEM MODULE





When Monitored and Set Condition

- When Monitored: Continuous.
- Set Condition: CAN Bus communication failure between the Body Control Module (BCM) and the Central Locking Pump/Security System Module (CLP/SSM).





For a complete Body Control Module Circuit Diagram. Body - Electrical Diagnostics.

Diagnostic Test

1. MEASURE THE RESISTANCE OF THE CAN B BUS (+) CIRCUIT




Turn the ignition off.
Disconnect the CLP/SSM harness connector.
Disconnect the BCM harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance of the CAN B Bus (+) circuit from the CLP/SSM harness connector to the BCM harness connector.
Is the resistance below 1.0 ohm?

Yes

- Go to 2

No

- Repair the CAN B Bus (+) circuit for an open.
- Perform BODY VERIFICATION TEST. Body Verification Test

2. MEASURE THE RESISTANCE OF THE CAN B BUS (-) CIRCUIT




Measure the resistance of the CAN B Bus (-) circuit from the CLP/SSM harness connector to the BCM harness connector.
Is the resistance below 1.0 ohm?

Yes

- Replace the Central Locking Pump/Security System Module. Sentry Key Remote Entry Module - Removal.
- Perform BODY VERIFICATION TEST. Body Verification Test

No

- Repair the CAN B Bus (-) circuit for an open.
- Perform BODY VERIFICATION TEST. Body Verification Test