Inspection Procedure 39: Engine Oil Level Sensor System








OPERATION



  • A power voltage of 5 V is applied to the engine oil level sensor output terminal (terminal No. 1) from the engine-ECU (terminal No. 54).
  • The power voltage is earthed to the engine-ECU (terminal No. 95) from the engine coolant temperature sensor (terminal No. 3).

FUNCTION



  • The engine oil level sensor converts the engine oil level into the voltage, and outputs the information to the engine-ECU.

PROBABLE CAUSES



  • Failed engine oil level sensor
  • Open/short circuit or harness damage in engine oil level sensor circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-112 engine oil level sensor connector

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

STEP 2. Perform resistance measurement at B-112 engine oil level sensor connector.

  • Disconnect connector, and measure at the harness side.
  • Voltage between terminal No. 3 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 6 .
Go to Step 3 .

STEP 3. Connector check: B-17 engine-ECU connector

Q. Is the check result normal?
Go to Step 4 .
Repair or replace the connector.

STEP 4. Check harness between B-112 (terminal No. 3) engine oil level sensor connector and B-17 (terminal No. 95) engine-ECU connector.

  • Check earthing line for open circuit and damage.

Q. Is the check result normal?
Go to Step 5 .
Repair the damaged harness wire.

STEP 5. Check the trouble symptoms.

Q. Does trouble symptom persist?

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

STEP 6. Perform voltage measurement at B-112 engine oil level sensor connector.

  • Disconnect connector, and measure at the harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
OK: 4.5 - 4.9 V

Q. Is the check result normal?
Go to Step 9 .
Go to Step 7 .

STEP 7. Connector check: B-17 engine-ECU connector

Q. Is the check result normal?

Go to Step 8 .
Repair or replace the connector.

STEP 8. Check harness between B-112 (terminal No. 1) engine oil level sensor connector and B-17 (terminal No. 54) engine-ECU connector.

  • Check output line for open/short circuit.

Q. Is the check result normal?
Go to Step 5 .
Repair the damaged harness wire.

STEP 9. Connector check: B-17 engine-ECU connector

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

STEP 10. Check harness between B-112 (terminal No. 1) engine oil level sensor connector and B-17 (terminal No. 54) engine-ECU connector.

  • Check output line for damage.

Q. Is the check result normal?
Go to Step 11 .
Repair or replace the connector.

STEP 11. Replace the engine oil level sensor.

  • After replacing the engine oil level sensor, re-check the trouble symptoms.

Q. Does trouble symptom persist?

Replace the engine-ECU.
The check is end.