Code No. U1211: Engine Parity/Toggle Bit Error



caution If diagnosis code U1211 is set from AS&G-ECU, surely perform CAN bus line diagnosis.
caution Replace ECU after certainly confirming that the communication circuits are normal.

TROUBLE JUDGMENT


Check Conditions
Judgement Criterion

COMMENTS ON TROUBLE SYMPTOM


Current malfunction
Past malfunction
FAIL-SAFE AND BACKUP FUNCTION

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


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


Use M.U.T.-III to perform CAN bus line diagnosis.

Q. Is the check result normal?

Go to Step 2.
Repair CAN bus line (Refer to GROUP 54C - Troubleshooting - CAN Bus Diagnosis Chart ). After repairing CAN bus line, go to Step 5.

STEP 2. M.U.T.-III diagnosis code for other systems


Confirm the diagnosis code is set from the engine-ECU.

Q. Is the diagnosis code set?

Perform troubleshooting of the engine (Refer to GROUP 13C - Troubleshooting - Diagnosis Code Chart ).
Go to Step 3.

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



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the AS&G-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: "LOCK" (OFF) → "ON"
  3. Confirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

After replacing the engine-ECU, go to Step 4.
Intermittent malfunction in CAN bus line between AS&G-ECU and engine-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).

STEP 4. M.U.T.-III diagnosis code



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the AS&G-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: "LOCK" (OFF) → "ON"
  3. Confirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

After replacing the AS&G-ECU, go to Step 5.
Intermittent malfunction in CAN bus line between AS&G-ECU and engine-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).

STEP 5. M.U.T.-III diagnosis code



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the AS&G-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: "LOCK" (OFF) → "ON"
  3. Confirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

Go to Step 1.
Check end.