Engine Oil Pressure Gage Inaccurate or Inoperative

Engine Oil Pressure Gage Inaccurate or Inoperative

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 provides an overview of each diagnostic category.

Diagnostic Fault Information






Circuit/System Description

The engine oil pressure (EOP) sensor changes voltage based on the engine oil pressure. The EOP sensor is a 3-wire sensor comprising of the signal circuit, the low reference circuit and the 5-volt reference circuit. The engine control module (ECM) or the powertrain control module (PCM) supplies 5 volts to the EOP sensor via the 5-volt reference circuit and provides ground via the EOP low reference circuit. The ECM/PCM monitors the signal circuit of the EOP sensor to determine the engine oil pressure sensor voltage is within the normal operating range of approximately 1-4 volts. When the engine oil pressure is high, the EOP sensor voltage is high and the ECM/PCM senses a high signal voltage. When the engine oil pressure is low, the EOP sensor voltage is low and the ECM/PCM senses a low signal voltage. The ECM/PCM sends the EOP information to the instrument panel cluster (IPC) via serial data messages.

Circuit/System Testing

Ignition ON, with the scan tool, perform the IPC Gage Sweep Test in the IPC Output Controls. Verify that the EOP gage dials moves from minimum to the maximum value and back to the EOP gage minimum value.

If the EOP gage does not perform the IPC Gage Sweep Test, replace the IPC.

Repair Instructions

Perform the Diagnostic Repair Verification

* Engine Oil Pressure Sensor and/or Switch Replacement for the 4.6L engine
* Engine Oil Pressure Sensor and/or Switch Replacement for the 4.4L engine
* Programming and RelearningProgramming and Relearning>