DTC P0606: Engine-ECU or Engine-A-M/T-ECU Main Processor Malfunction




OPERATION




FUNCTION




TROUBLE JUDGMENT


Check Condition
Judgement Criterion

PROBABLE CAUSE




DIAGNOSIS PROCEDURE


STEP 1. Check battery.



  • Battery check (Refer to GROUP 54A - Battery - On-vehicle Service - Battery Test ).

Q. Is the check result normal?

Go to Step 2 .
Replace the battery.

STEP 2. Connector check: A-09 engine-ECU or engine-A-M/T-ECU connector



Q. Is the check result normal?

Go to Step 3 .

Repair or replace the connector.

STEP 3. Perform voltage measurement at A-09 engine-ECU or engine-A-M/T-ECU connector.




  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 122 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 5 .

Go to Step 4 .

STEP 4. Connector check: B-240 ignition switch connector




Q. Is the check result normal?


    Check intermediate connectors B-210 and B-229, and repair if necessary. If intermediate connectors are normal, check and repair harness between B-240 (terminal No. 2) ignition switch connector and A-09 (terminal No. 122) engine-ECU or engine-A-M/T-ECU connector.

    • Check signal line for open/short circuit.

Repair or replace the connector.

STEP 5. Connector check: B-240 ignition switch connector



Q. Is the check result normal?

Go to Step 6 .

Repair or replace the connector.

STEP 6. Check harness between B-240 (terminal No. 2) ignition switch connector and A-09 (terminal No. 122) engine-ECU or engine-A-M/T-ECU connector.




note Before checking harness, check intermediate connectors B-210 and B-229, and repair if necessary.

  • Check signal line for damage.

Q. Is the check result normal?

Go to Step 7 .

Repair the damaged harness wire.

STEP 7. Connector check: B-206 engine control relay connector



Q. Is the check result normal?

Go to Step 8 .

Repair or replace the connector.

STEP 8. Check engine control relay itself.



  • Check engine control relay itself (Refer to ).

Q. Is the check result normal?

Go to Step 9 .
Replace the engine control relay.

STEP 9. Check harness between B-206 (terminal No. 2) engine control relay connector and A-09 (terminal No. 107) engine-ECU or engine-A-M/T-ECU connector.





  • Check signal line for short circuit.

Q. Is the check result normal?

Go to Step 10 .

Repair the damaged harness wire.

STEP 10. M.U.T.-III diagnosis code



  • Reconfirmation of diagnosis code.

Q. Is diagnosis code set?

Replace the engine-ECU or engine-A-M/T-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).