Engine Oil Pressure Indicator Always On

Engine Oil Pressure Indicator Always On

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provide an overview of each diagnostic category.

Circuit/System Description

The engine oil pressure (EOP) switch is a normally closed switch that opens with the proper oil pressure. With the ignition switch turned ON and the engine not running, the engine control module (ECM)/powertrain control module (PCM) should detect a low signal voltage input. With the engine running, the pressure switch opens, and the ECM/PCM should detect a high signal voltage input.

Circuit/System Testing

1. Ignition ON, engine ON, verify the scan tool Low Oil Pressure Switch parameter is Closed or the scan tool Low Oil Pressure parameter is Yes.

• If not Closed or Yes, replace the instrument panel cluster (IPC).

2. Ignition OFF, disconnect the harness connector at the EOP switch.
3. Ignition ON, verify the scan tool Low Oil Pressure Switch parameter is Open or the scan tool Low Oil Pressure parameter is No.

• If not Open or No, test the signal circuit of the EOP switch for a short to ground. If the circuit tests normal, replace the ECM/PCM.

4. If all circuits test normal, test or replace the EOP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Engine Oil Pressure Sensor and/or Switch Replacement for the 2.2L engine
* Engine Oil Pressure Sensor and/or Switch Replacement for the 2.4L engine
* Engine Oil Pressure Sensor and/or Switch Replacement for the 3.5L engine
* Control Module References for ECM/PCM replacement, setup, and programming