GM Service Manual Online
For 1990-2009 cars only

Powertrain Control Module Inputs Diagnosis Engine Oil Pressure Switch

Refer to

IAC Valve, Generator, TR, Oil, and Coolant Switches


Object Number: 184694  Size: FS
Engine Controls Components
Information Sensors/Switches Description
VSS and Cruise Control
Oxygen Sensors
OBDII Symbol Description Notice
Handling Electrostatic Discharge Sensitive Parts Notice
schematic.

Circuit Description

The Engine Oil Pressure Indicator is controlled by the Instrument Panel Cluster (IPC) via serial data from the Powertrain Control Module (PCM) . The Oil Pressure Indicator will also light when the engine is running if the engine oil pressure drops below approximately 13.8 kPa. (2 psi.).

As a bulb check procedure, the IPC will command this telltale ON when the IPC and PCM are powered up.

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Are any PCM DTC(s) stored?

--

Go to applicable DTCs

Go to Step 3

3

Is the Engine Oil pressure Indicator ON?

--

Go to Step 4

Go to Step 12

4

Check the engine for correct oil level. Refer to Fluid and Lubricant Recommendations in Maintenance and Lubrication.

Is the Correct engine oil level indicated?

--

Go to Step 5

Go to Step 10

5

Check the engine oil pressure with a manual pressure gauge.

Refer to Oil Pressure Diagnosis and Testing in Engine Mechanical.

Is proper engine oil pressure indicated?

--

Go to Step 6

Go to Step 11

6

Disconnect the PCM harness connector and the Engine Oil Pressure Sensor Connector and check the oil pressure sensor input circuit for the following:

    •  Open circuit
    •  Shorts to ground
    •  Short to battery positive voltage
    •  Check for poor or corroded connections.

If a problem is found repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a Problem Found?

--

Go to Step 12

go to step 7

7

Check the Communication circuit for correct operation.

Was a problem Found?

--

Go to Step 12

go to step 8

8

Check engine oil pressure sensor indicator for correct operation. Refer to Instrument Cluster System Check in Instrument Panel, Gauges and Console.

If a problem is found repair as necessary.

Was a problem found?

--

Go to Step 12

Go to Step 9

9

Replace Engine Oil Pressure Sensor.

Is the action complete?

--

Go to Step 12

--

10

Determine cause of low oil. Refer to Oil Consumption Diagnosis Engine Mechanical.

Is the action complete?

Go to Step 12

--

11

Determine cause of low oil pressure. Refer to Oil Pressure Diagnosis and Testing in Engine Mechanical.

Is the action complete?

Go to Step 12

--

12

Check for the proper operation of Oil Pressure Indicator. Refer to Instrument Cluster System Check in Instrument Panel, Gauges and Console.

Is the correct operation indicated?

System OK

go to step 2