Operation CHARM: Car repair manuals for everyone.

A/T

DTC U0001: Can Bus Off

DESCRIPTIONS OF MONITOR METHODS
^ Open circuit or short circuit occurs in the CAN communication line (CAN_H, CAN_L).
^ The communication becomes impossible with all the control modules for a specified time.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
^ Malfunction of the CAN circuit
^ Malfunction of the TCM
^ Damaged harness or connector
^ Malfunction of the CAN system module

DIAGNOSIS

STEP 1. Check the CAN communication system malfunction.
^ Check that the CAN system-related DTC code other than U0001 is set.
^ Check that the CAN-related DTC is set with other relevant modules.

Q:Is the check result normal?
YES: Go to Step 2.
NO: Repair or replace the failure section.

STEP 2. Check the CAN communication lines.
[C-38 TCM connector (vehicle side, disconnected)]

Between C-38 terminal No. 10, 11 and the CAN communication lines of other ECU: Continuity exists.

When the continuity check result is OK, check that the wiring harness is not shorted to the body and other wiring harness. Also, check for a short circuit between the twisted pair cables.

Q:Is the check result normal?
YES: Go to Step 3.
NO: Repair or replace the failure section.

STEP 3. Check the relevant ECUs and the TCM connector pin terminal, and the connection status.

Q:Is the check result normal?
YES: Repair or replace the failure section.
NO: Replace the TCM.