GM Service Manual Online
For 1990-2009 cars only

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for a short to ground in the signal circuit.

  2. This step tests for an open, for a high resistance, or for a short to voltage in the signal circuit.

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Start the engine.

Does the engine oil pressure gage display within the specified range?

10-70 psi (69-483 kPa)

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn the ignition OFF.
  2. Disconnect the engine oil pressure sensor.
  3. Start the engine.

Does the engine oil pressure gage display at or above the specified value?

80 psi (550 kPa)

Go to Step 4

Go to Step 6

4

  1. Turn the ignition OFF.
  2. Connect a 3 ampere fused jumper between the signal circuit of the engine oil pressure sensor and a good ground.
  3. Start the engine.

Does the engine oil pressure gage display at or below the specified value?

0 psi (0 kPa)

Go to Step 7

Go to Step 5

5

Test the signal circuit of the engine oil pressure sensor for an open, for a high resistance, or for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

6

Test the signal circuit of the engine oil pressure sensor for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

7

Inspect for a high resistance or for a poor connection at the case ground of the engine oil pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 8

8

Inspect for poor connections at the harness connector of the engine oil pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 10

9

Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 11

10

Replace the engine oil pressure sensor. Refer to the appropriate procedure:

    •  Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical - 4.3 L
    •  Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical - 5.0 L and 5.7 L
    •  Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical - 6.5 L
    •  Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical - 8.1 L

Did you complete the replacement?

--

Go to Step 12

--

11

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 12

--

12

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2