Code No. P1021: Intake Oil Feeder Control Valve System










OPERATION



  • Power is supplied to the intake oil feeder control valve (terminal No. 2) from the engine control relay (terminal No. 2).
  • The engine-ECU (terminal No. 1) makes the power transistor in the unit be in ON position, and that makes currents go on the intake oil feeder control valve (terminal No. 1).

FUNCTION



  • The engine-ECU controls the spool valve position of the intake oil feeder control valve corresponding to the driving condition of the engine and continuously changes the phase of the intake camshaft.

TROUBLE JUDGMENT


Check Conditions
  • Ignition switch is "ON" position.
  • Intake oil feeder control valve is OFF.
  • Battery positive voltage is more than 11 V and is less than 16.5 V.
Judgement Criterion
  • The engine-ECU terminal voltage of intake oil feeder control valve circuit is less than 4 V for 2 seconds.

PROBABLE CAUSES



  • Failed intake oil feeder control valve
  • Open/short circuit or harness damage in intake oil feeder control valve circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-35 intake oil feeder control valve connector

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

STEP 2. Check intake oil feeder control valve itself.

  • Check intake oil feeder control valve itself (Refer to ).

Q. Is the check result normal?
Go to Step 3 .
Replace the intake oil feeder control valve.

STEP 3. Perform voltage measurement at B-35 intake oil feeder control valve connector.

  • Disconnect connector and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 2 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 5 .
Go to Step 4 .

STEP 4. Connector check: A-33X engine control relay connector

Q. Is the check result normal?

    Check intermediate connector A-13, and repair if necessary.If intermediate connector is normal, check and repair harness between A-33X (terminal No. 2) engine control relay connector and B-35 (terminal No. 2) intake oil feeder control valve connector.

    • Check power supply line for open/short circuit.
Repair or replace the connector.

STEP 5. Perform voltage measurement at B-29 engine-ECU connector.

  • Disconnect connector and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 7 .
Go to Step 6 .

STEP 6. Connector check: B-29 engine-ECU connector

Q. Is the check result normal?

    Check and repair harness between B-35 (terminal No. 1) intake oil feeder control valve connector and B-29 (terminal No. 1) engine-ECU connector.

    • Check output line for open/short circuit.
Repair or replace the connector.

STEP 7. Connector check: A-33X engine control relay connector

Q. Is the check result normal?
Go to Step 8 .
Repair or replace the connector.

STEP 8. Check harness between A-33X (terminal No. 2) engine control relay connector and B-35 (terminal No. 2) intake oil feeder control valve connector.
note Before checking harness, check intermediate connector A-13, and repair if necessary.

  • Check power supply line for damage.

Q. Is the check result normal?
Go to Step 9 .
Repair the damaged harness wire.

STEP 9. Connector check: B-29 engine-ECU connector

Q. Is the check result normal?
Go to Step 10 .
Repair or replace the connector.

STEP 10. Check harness between B-35 (terminal No. 1) intake oil feeder control valve connector and B-29 (terminal No. 1) engine-ECU connector.

  • Check output line for damage.

Q. Is the check result normal?
Go to Step 11 .
Repair the damaged harness wire.

STEP 11. M.U.T.-III diagnosis code

  • Reconfirmation of diagnosis code.

Q. Is diagnosis code set?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).