Pinpoint Test Be: Can Bus Failure: Notes

Refer to appropriate Supplemental Restraint System in OEM Wiring Diagrams article, for schematic and connector information.

Normal Operation and Fault Conditions

The RCM communicates with other modules on the HS-CAN. When the ignition is first turned ON, the RCM will attempt to initialize itself on the HS-CAN.

If the RCM cannot initialize on the HS-CAN, or if it cannot communicate with any other module, the RCM stores DTC U0001:88 or U1A14:55 in memory and sends a message to the IPC to illuminate the airbag warning indicator.

PPT BE RCM DTC FAULT TRIGGER CONDITIONS

DTC	Description	Fault Trigger Conditions
U0001:88	High Speed CAN Communication Bus: Bus Off	Sets when the RCM cannot communicate on the HS-CAN with any module.
U1A14:55	CAN Initialisation Failure: Not Configured	Sets when the RCM cannot initialize on the HSCAN when the module receives ignition voltage.

Possible Causes

Wiring, terminals or connectors
RCM

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.

NOTE: SRS components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.

NOTE: Always make sure the correct SRS component is being installed. Parts released for other vehicles may not be compatible even if they appear physically similar. Check the part number listed in the Ford parts catalog to make sure the correct component is being installed. If an incorrect SRS component is installed, DTCs may set.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

Restraint Control Module-B (RCM-B) Connector - C310B

Circuit	Pin
HS-CAN1 - (High Speed Controller Area Network 1-) - VDB05	47(WHITE)
HS-CAN1 + (High Speed Controller Area Network 1+) - VDB04	48(WHITE/BLUE)

Data Link Connector (DLC) Connector - C251

Circuit	Pin
HS-CAN1 - (High Speed Controller Area Network 1-) - VDB05	14(WHITE)
HS-CAN1 + (High Speed Controller Area Network 1+) - VDB04	6(WHITE/BLUE)