Code No. U1073: Bus Off


caution If diagnosis code U1073 is output from engine-A/T-ECU, surely perform CAN busline diagnosis.
caution Replace ECU after certainly confirming that the communication circuits are normal.

TROUBLE JUDGMENT


Check Condition
Judgment Criterion
COMMENT ON TROUBLE SYMPTOM

PROBABLE CAUSE



DIAGNOSIS

STEP 1. M.U.T.-III CAN bus diagnosis

  • Using M.U.T.-III, perform CAN busline diagnosis.

Q. Is the check result normal?
Go to Step 2 .
Correct CAN busline (Refer to 54F - Diagnosis - Can Bus Diagnostics Chart ), and then go to Step 3 .

STEP 2. M.U.T.-III diagnosis code

  • Reconfirm whether the diagnosis code is output from engine-A/T-ECU.

  1. Erase the diagnosis code being output.
  2. Ignition switch: LOCK (OFF) to ON
  3. Confirm whether the diagnosis code is output.

Q. Is the diagnosis code set?
Replace engine-A/T-ECU, then go to Step 3 .
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points ).

STEP 3. M.U.T.-III diagnosis code

  • Reconfirm whether the diagnosis code is output from engine-A/T-ECU.

  1. Erase the diagnosis code being output.
  2. Ignition switch: LOCK (OFF) to ON
  3. Confirm whether the diagnosis code is output.

Q. Is the diagnosis code set?
Go to Step 1 .
Check end.