Code No. P1021: Inlet Oil Feeder Control Valve System

OPERATION

Power is supplied to the inlet 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 inlet oil feeder control valve (terminal No. 1).

FUNCTION

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

TROUBLE JUDGMENT

Check Condition

Operation of the inlet oil feeder control valve: OFF (ignition switch: ON, during idling etc.)

Judgement Criterion

The inlet oil feeder control valve drive terminal voltage of the engine-ECU is not normal for 2 seconds or more.

FAIL-SAFE AND BACKUP FUNCTION

V.V.T. phase angle (inlet) becomes most retarded angle.

PROBABLE CAUSES

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

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-22 inlet oil feeder control valve connector

Q. Is the check result normal?

	Go to Step 2.

	Repair or replace the connector.

STEP 2. Check inlet oil feeder control valve itself.

Check inlet oil feeder control valve itself (Refer to ).

Q. Is the check result normal?

	Go to Step 3.

	Replace the inlet oil feeder control valve.

STEP 3. Perform voltage measurement at B-22 inlet 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-70, 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-22 (terminal No. 2) inlet oil feeder control valve connector. Check power supply line for open/short circuit.

	Repair or replace the connector.

STEP 5. Connector check: B-08 engine-ECU connector

Q. Is the check result normal?

	Go to Step 6.

	Repair or replace the connector.

STEP 6. Perform voltage measurement at B-08 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.

	Check and repair harness between B-22 (terminal No. 1) inlet oil feeder control valve connector and B-08 (terminal No. 1) engine-ECU connector. Check output line for open/short circuit.

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-22 (terminal No. 2) inlet oil feeder control valve connector.

note

Before checking harness, check intermediate connector A-70, 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. Check harness between B-22 (terminal No. 1) inlet oil feeder control valve connector and B-08 (terminal No. 1) engine-ECU connector.

Check output line for damage.

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.

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).