CAN Bus Communication General Malfunction

CAN BUS COMMUNICATION GENERAL MALFUNCTION





When Monitored and Set Condition
^ When Monitored: With the ignition on.
^ Set Condition: CAN Bus communication failure between the Controller Antilock Brake (CAB) and the CAN Bus network.





For a complete Brake Assist System (BAS) Circuit Diagram refer to Diagrams; Electrical
Diagnostic Test
1. MEASURE THE RESISTANCE OF THE CAN C BUS (+) CIRCUIT
Turn the ignition off.
Disconnect the CAB harness connector.
Disconnect the harness connectors of the other modules on the CAN Bus network.

Note: Check connectors - Clean/repair as necessary.





Measure the resistance of the CAN C Bus (+) circuit from the CAB harness connector to the harness connectors of the other modules on the CAN Bus network.
Is the resistance below 1.0 ohm?
Yes >> Go to 2
No >> Repair the CAN C Bus (+) circuit for an open. Perform ABS VERIFICATION TEST. ABS Verification Test

2. MEASURE THE RESISTANCE OF THE CAN C (-) BUS CIRCUIT
With the ignition off.





Measure the resistance of the CAN C Bus (-) circuit from the CAB harness connector to the harness connectors of the other modules on the CAN Bus network.
Is the resistance below 1.0 ohm?
Yes >> Replace the Controller Antilock Brake. Perform ABS VERIFICATION TEST.
No >> Repair the CAN C Bus (-) circuit for an open. Perform ABS VERIFICATION TEST.