U0001

DTC U0001 CAN COMMUNICATION BUS OFF





COMPONENT LOCATION

GENERAL DESCRIPTION
The TCM can either receive data from the Engine Control Module or ABS control module, or it can send data to the ECM and ABSCM by using CAN communication. The CAN communicator is one of the vehicle communications method, which is now widely used to transfer the vehicle data.

DTC DESCRIPTION
When the TCM cannot read the data from the ECM through the CAN-BUS line, the TCM sets this code. CAN-BUS circuit malfunctioning or ECM can be a possible cause of this DTC.





DTC DETECTING CONDITION

MONITOR SCANTOOL DATA
1. Connect scantool to data link connector (DLC).
2. Engine "ON".
3. Monitor the "CAN COMMUNICATION SERVICE DATA (ENGINE RPM, VEHICLE SPEED SENSOR, THROTTLE P. SENSOR)" parameters on the scantool.





4. Compare it with reference data as below.
5. Does "CAN BUS LINE DATA" follow the reference data?
YES >>
^ Fault is intermittent caused by poor contact in the sensor's and/or PCM/TCM's connector or was repaired and PCM/TCM memory was not cleared. And go to Verification of Vehicle Repair procedure.
NO >>
^ Substitute with a known-good PCM/TCM and check for proper operation. If the problem is corrected, replace PCM/TCM as necessary and then go to "Verification of Vehicle Repair" procedure.

VERIFICATION OF VEHICLE REPAIR
Refer to DTC P0560. P0560