Tests BK: DTC U0073 - Control Module Communication Bus Off
PINPOINT TEST BK: DTC U0073 - CONTROL MODULE COMMUNICATION BUS OFFBK1-BK3:
BK3-BK5:
BK6:
NOTE: DTC U0073 can only be retrieved as a continuous fault.
Normal Operation
This vehicle utilizes a communication system called a high-speed controller area network (HS-CAN). The HS-CAN consists of a twisted pair of wires connected to various modules on the vehicle.
The restraints control module (RCM) checks the HS-CAN circuits for faults. If the RCM detects a fault on the HS-CAN circuits, it will store diagnostic trouble code (DTC) U0073 in memory.
Fault Conditions
The RCM monitors the HS-CAN circuits for the following fault conditions:
- Open circuit
- Short to ground
- Short to voltage
Possible Causes
A control module communication bus off fault can be caused by:
- damaged wiring, terminals or connectors.
- a faulted ABS module.
- a faulted generic electronic module (GEM).
- a faulted instrument cluster module.
- a faulted powertrain control module (PCM).
- a faulted RCM.