Code No. P1025: Exaust Oil Feeder Control Valve System










OPERATION



  • Power is supplied to the exhaust oil feeder control valve (terminal No. 2) from the engine control relay (terminal No. 2).
  • The engine-ECU (terminal No. 17) makes the power transistor in the unit be in ON position, and that makes currents go on the exhaust oil feeder control valve (terminal No. 1).

FUNCTION



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

TROUBLE JUDGMENT


Check Condition
  • Ignition switch is "ON" position.
  • Exhaust 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 exhaust oil feeder control valve circuit is less than 4 V for 2 seconds.

FAIL-SAFE AND BACKUP FUNCTION



  • V.V.T. phase angle (exhaust) becomes most advanced angle.

PROBABLE CAUSES



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

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-17 exhaust oil feeder control valve connector

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

STEP 2. Check exhaust oil feeder control valve itself.

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

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

STEP 3. Perform voltage measurement at B-17 exhaust 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-11, 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-17 (terminal No. 2) exhaust 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. 17 and earth.
OK: System voltage

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

    Check and repair harness between B-17 (terminal No. 1) exhaust oil feeder control valve connector and B-08 (terminal No. 17) 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-17 (terminal No. 2) exhaust oil feeder control valve connector.
note Before checking harness, check intermediate connector A-11, 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-17 (terminal No. 1) exhaust oil feeder control valve connector and B-08 (terminal No. 17) 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 ).