Low Oil Pressure Indicator Circuit Troubleshooting - Short

Low Oil Pressure Indicator Circuit Troubleshooting - Short

1. Connect the HDS to the DLC.

2. Turn the ignition switch to ON (II).

3. Make sure the HDS communicates with the vehicle and the ECM. If it does not communicate, troubleshoot the DLC circuit Testing and Inspection.

4. Check for DTCs Initial Inspection and Diagnostic Overview. If a DTC is present, diagnose, and repair the cause before continuing with this test.

5. Start the engine, and check the OIL PRESSURE SWITCH in the PGM-FI DATA LIST with the HDS.

Is OFF indicated?

YES -

Replace the gauge control module (tach).�

NO -

Go to step 6.

6. Turn the ignition switch to LOCK (0).

7. Check the oil pressure switch Testing and Inspection.

Is the oil pressure switch OK?

YES -

Go to step 8.

NO -

Do the oil pressure test Testing and Inspection. If the oil pressure is OK, replace the oil pressure switch Service and Repair.�

8. Turn the ignition switch to ON (II), and jump the SCS line with the HDS, then turn the ignition switch to LOCK (0).

NOTE: This step must be done to protect the ECM from damage.

9. Disconnect ECM connector B (44P) and the oil pressure switch connector.

10. Check for continuity between the oil pressure switch connector and body ground.





Is there continuity?

YES -

Repair a short to ground in the wire between the oil pressure switch and ECM connector terminal B7.�

NO -

Update the ECM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM Service and Repair.�