Inspection Procedure 34: Oil Pressure Switch System




OPERATION



FUNCTION



PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Perform voltage measurement at A-08 engine-ECU connector.


  • Engine-ECU connector, and connect special tool power plant ECU check harness (MB991987), and then measure the voltage on the check connector.
  • Voltage between terminal No. 50 and earth.
OK:
    System voltage (Idling after warming up)
    0.5 V or less (Ignition switch: ON)

Q. Is the check result normal?

Check combination meter (Refer to GROUP 54A - Combination Meter - Check Chart for Trouble Symptoms <COLT>, <COLT CZ3>).

Go to Step 2 .

STEP 2. Connector check: A-08 engine-ECU connector

Q. Is the check result normal?

Go to Step 3 .

Repair or replace the connector.

STEP 3. Check harness between A-120 (terminal No. 1) Oil pressure switch connector and A-08 (terminal No. 50) engine-ECU connector.



  • Check output line for open/short circuit and damage.

Q. Is the check result normal?

Go to step 4 .

Repair.

STEP 4. Connector check: A-120 Oil pressure switch connector

Q. Is the check result normal?

Go to step 5 .

Repair.

STEP 5. Oil pressure check

  • Oil pressure check (Refer to GROUP 12 - On-Vehicle Service - Oil Pressure Check ).

Q. Is the check result normal?
Go to Step 6 .
Repair the oil pressure.

STEP 6. Replace the oil pressure switch

  • After replacing the oil pressure switch, re-check the trouble symptoms.

Q. Does trouble symptom persist?
Replace the engine-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service - How to Perform Variant Coding ).
Check end.