GM Service Manual Online
For 1990-2009 cars only

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

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

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

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the IPC Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Start the engine.

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

0-73 psi (0-500 kPa)

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

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect C102.
  3. Connect the J 33431-C Signal Generator and Instrument Panel Tester (male side) between the engine oil pressure gage sensor signal circuit and ground.
  4. Turn the igntion ON with the engine OFF.
  5. Dial the signal generator to 200ohms, 140ohms, and 1.2ohms.

Important: Verify the J 33431-C resistance setting with a DMM.

Does the engine oil pressure gage display 80 psi, 40 psi, and 0 psi for each value listed above?

--

Go to Step 4

Go to Step 5

4

Test the signal circuit of the engine oil pressure gage switch for an open, a high resistance, a short to ground, or a short to voltage between C102 and the engine oil pressure gage sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

Go to Step 6

5

Test the signal circuit of the engine oil pressure gage sensor for an open, a high resistance, short to ground, or a short to voltage between the IPC and C102. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

Go to Step 7

6

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

Did you find and correct the condition?

--

Go to Step 10

Go to Step 8

7

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

Did you find and correct the condition?

--

Go to Step 10

Go to Step 9

8

Replace the engine oil pressure gage sensor. Refer to Engine Oil Pressure Sensor or Switch Replacement .

Did you complete the replacement?

--

Go to Step 10

--

9

Important: Program the replacement IPC.

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2