Inspection Procedure 27: Oil pressure switch system

OPERATION

Battery voltage is applied to the oil pressure switch (terminal No. 1) from the engine-ECU <M/T> or engine-A/T-ECU <A/T> (terminal No. 27).

FUNCTION

Detect the engine oil pressure conditions and enter the result into the engine-ECU <M/T> or engine-A/T-ECU <A/T>. After starting the engine if the oil pressure rises to higher than the given pressure, the engine oil pressure switch turns OFF.Under this condition the engine-ECU <M/T> or engine-A/T-ECU <A/T> sends the command of turning off the oil warning lamp to the combination meter via CAN.

PROBABLE CAUSES

Failed oil pressure switch
Open/short circuit in the oil pressure switch circuit or loose connector contact
Failed engine-ECU <M/T> or engine-A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-102 oil pressure switch connector

Q. Is the check result normal?

	Go to Step 2 .

	Repair or replace the connector.

STEP 2. Perform measurement at B-102 oil pressure switch connector

Disconnect connector and measure at the harness side.
Ignition switch: ON
Voltage between terminal No. 1 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 8 .

	Go to Step 3 .

STEP 3. Perform voltage measurement at D-243 engine-ECU <M/T> connector or D-212 engine-A/T-ECU <A/T> connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Voltage between terminal No. 27 and earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 4 .

	Go to Step 5 .

STEP 4. Connector check: D-243 engine-ECU <M/T> connector or D-212 engine-A/T-ECU <A/T> connector

Q. Is the check result normal?

	Check intermediate connector B-28, and repair if necessary.If intermediate connector is normal, check and repair harness between B-102 (terminal No.1) oil pressure switch connector and D-243 (terminal No. 27) engine-ECU <M/T> connector or D-212 (terminal No. 27) engine-A/T-ECU <A/T> connector. Check output line for open circuit.

	Repair or replace the connector.

STEP 5. Connector check: D-243 engine-ECU <M/T> connector or D-212 engine-A/T-ECU <A/T> connector

Q. Is the check result normal?

	Go to Step 6 .

	Repair or replace the connector.

STEP 6. Check harness between B-102 (terminal No. 1) oil pressure switch connector and D-243 (terminal No. 27) engine-ECU <M/T> connector or D-212 (terminal No. 27) engine-A/T-ECU <A/T> connector.

note

Before checking harness, check intermediate connector B-28, and repair if necessary.

Check output line for short circuit.

Q. Is the check result normal?

	Go to Step 7 .

	Repair the damaged harness wire.

STEP 7. M.U.T.-III data list

Refer to Data List Reference Table .

Item 90: Oil pressure switch

Q. Is the check result normal?

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

	Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.

STEP 8. Perform voltage measurement at D-243 engine-ECU <M/T> connector or D-212 engine-A/T-ECU <A/T> connector.

Disconnect connector, and measure at harness side.
Engine: Idling
Voltage between terminal No. 27 and earth.

OK:
1 V or less (ignition switch: ON)
System voltage (during idling)

Q. Is the check result normal?

	Go to Step 11 .

	Go to Step 9 .

STEP 9. Connector check: D-243 engine-ECU <M/T> connector or D-212 engine-A/T-ECU <A/T> connector

Q. Is the check result normal?

	Go to Step 10 .

	Repair or replace the connector.

STEP 10. Check harness between B-102 (terminal No. 1) oil pressure switch connector and D-243 (terminal No. 27) engine-ECU <M/T> connector or D-212 (terminal No. 27) engine-A/T-ECU <A/T> connector.

note

Before checking harness, check intermediate connector B-28, and repair if necessary.

Check output line for damage.

Q. Is the check result normal?

	Replace the oil pressure switch.

	Repair the damaged harness wire.

STEP 11. Connector check: D-243 engine-ECU <M/T> connector or D-212 engine-A/T-ECU <A/T> connector

Q. Is the check result normal?

	Go to Step 7 .

	Repair or replace the connector.