Code No. U0100: Engine-ECU Time-out


DIAGNOSIS CODE SET CONDITIONS
  • Open circuit or short circuit occurs in the CAN communication line (CAN_H, CAN_L).
  • Reception from engine-ECU becomes impossible for a specified time or more.

PROBABLE CAUSES



  • Damaged harness or connector
  • Malfunction of the CAN communication
  • Malfunction of the engine-ECU
  • Malfunction of the A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check the CAN communication system malfunction.

  • Check that the CAN system-related diagnosis code other than U0100 is set.

  • Check if the CAN-related diagnosis code is set with engine-ECU.

  • Check if the failure related to the engine occurs.

Q. Is the check result normal?
Go to Step 2.
Repair or replace the failure section.

STEP 2. Check the CAN communication lines.
[C-138 A/T-ECU connector (vehicle side, disconnected)]
Between C-138 terminal No. 10, 11 and the CAN communication lines of engine-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?
Go to Step 3.
Repair or replace the failure section.

STEP 3. Check engine-ECU, the A/T-ECU connector pin terminal, and the connection status.

Q. Is the check result normal?
Repair or replace the failure section.
Replace the A/T-ECU.