GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the instrument cluster diagnostic system check?

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Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Turn ON the ignition.

Does the ENGINE OIL PRESSURE message display?

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Go to Step 3

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

3

  1. Turn ON the ignition, with the engine OFF.
  2. Install a scan tool.
  3. With a scan tool, select the PCM IPC data list screen on the scan tool.

  4. Check the engine oil pressure data value.

Does the engine oil pressure data value indicate low?

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Go to Step 5

Go to Step 4

4

Important: Perform the set up procedure for the replacement IPC.

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement and the set up procedure?

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Go to Step 10

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5

  1. Turn OFF the ignition.
  2. Disconnect the PCM connector C1.
  3. Test for a short to ground in the signal circuit of the engine oil pressure indicator switch. Refer to Circuit Testing in Wiring Systems.

Is a short to ground present?

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Go to Step 6

Go to Step 7

6

Disconnect the engine oil pressure indicator switch.

Is a short to ground still present?

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Go to Step 8

Go to Step 9

7

Important: Perform the reprogramming procedure for the replacement PCM.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls - 3.0L.

Did you complete the replacement and the set up procedure?

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Go to Step 10

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8

Repair a short to ground in the signal circuit of the engine oil pressure indicator switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 10

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9

Replace the engine oil pressure indicator switch. Refer to engine oil pressure switch replacement.

Did you complete the repair?

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Go to Step 10

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10

Operate the system in order to verify the repair. Did you correct the condition?

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System OK

Go to Step 3