DTC P0657: Throttle Valve Control Servo Relay Circuit Malfunction




OPERATION



FUNCTION



TROUBLE JUDGMENT


Check Condition
Judgement Criterion

PROBALE CAUSES



DIAGNOSIS

STEP 1. Connector check: B-221 throttle valve control servo relay connector

Q. Is the check result normal?

Go to Step 2 .

Repair or replace the connector.

STEP 2. Check throttle valve control servo relay itself.

  • Check throttle valve control servo relay (Refer to ).

Q. Is the check result normal?
Go to Step 3 .
Replace the throttle valve control servo relay.

STEP 3. Perform voltage measurement at B-221 throttle valve control servo relay connector.


  • Remove relay, and measure at J/B side.
  • Voltage between terminal No. 3 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 4 .


    Check intermediate connector B-208, and repair if necessary. if intermediate connector is normal, Check and repair harness between B-221 (terminal No. 3) throttle valve control servo relay connector and battery.

    • Check power supply line for open/short circuit.

STEP 4. Perform voltage measurement at B-221 throttle valve control servo relay connector.


  • Remove relay, and measure at J/B side.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 6 .

Go to Step 5 .

STEP 5. Connector check: B-206 engine control relay connector


Q. Is the check result normal?


    Check and repair harness between B-206 (terminal No. 4) engine control relay connector and B-221 (terminal No. 1) throttle valve control servo relay connector.

    • Check power supply line for open/short circuit.

Repair or replace the connector.

STEP 6. 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. 123 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 7 .


    Check intermediate connector B-210, and repair if necessary. If intermediate connector is normal, check and repair harness between B-221 (terminal No. 2) throttle valve control servo relay connector and A-09 (terminal No. 123) engine-ECU connector or engine-A-M/T-ECU connector.

    • Check earthing line for open/short circuit.

STEP 7. Perform voltage measurement at A-09 engine-ECU connector or engine-A-M/T-ECU connector.


  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Using a jumper wire, connect A-09 (terminal No. 123) engine-ECU connector or engine-A-M/T-ECU connector end earth.
  • Voltage between terminal No. 78 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 10 .

Go to Step 8 .

STEP 8. Check harness between B-221 (terminal No. 4) throttle valve control servo relay connector and A-09 (terminal No. 78) engine-ECU connector or engine-A-M/T-ECU connector.


note Before checking harness, check intermediate connector B-212, and repair if necessary.

  • Check power supply line for open/short circuit.

Q. Is the check result normal?

Go to Step 9 .

Repair the damaged harness wire.

STEP 9. Connector check: A-09 engine-ECU connector and engine-A-M/T-ECU connector.


  • Check output line for damage.

Q. Is the check result normal?


    Replace the engine-ECU or engine-A-M/T-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service - How to Perform Variant Coding).

    • Check earthing line for open/short circuit.

Repair or replace the connector.

STEP 10. Connector check: A-09 engine-ECU connector or engine-A-M/T-ECU connector

Q. Is the check result normal?

Go to Step 11 .

Repair or replace the connector.

STEP 11. Check and repair harness between B-221 (terminal No. 3) throttle valve control servo relay connector and battery.

note Before checking harness, check intermediate connector B-208, and repair if necessary.

  • Check power supply line for damage.

Q. Is the harness connector in good condition?

Go to Step 12 .

Repair the damaged harness wire.

STEP 12. Check and repair harness between B-221 (terminal No. 1) throttle valve control servo relay connector and B-206 (terminal No. 4) engine control relay connector.



  • Check power supply line for damage.

Q. Is the harness connector in good condition?

Go to Step 13 .

Repair the damaged harness wire.

STEP 13. Check and repair harness between B-221 (terminal No. 2) throttle valve control servo relay connector and A-09 (terminal No. 123) engine -ECU connector or engine-A-M/T-ECU connector.


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

  • Check power supply line for damage.

Q. Is the harness connector in good condition?

Go to Step 14 .

Repair the damaged harness wire.

STEP 14. Check and repair harness between B-221 (terminal No. 4) throttle valve control servo relay connector and A-09 (terminal No. 78) engine -ECU connector or engine-A-M/T-ECU connector.


note Before checking harness, check intermediate connector B-212, and repair if necessary.

  • Check power supply line for damage.

Q. Is the harness connector in good condition?

Go to Step 15 .

Repair the damaged harness wire.

STEP 15. M.U.T.-III diagnosis code.

  • Reconfirmation of diagnosis code.

Q. Is the diagnosis code set?
Replace the engine-ECU or engine-A-M/T-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service - How to Perform Variant Coding ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).