GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Turn the ignition switch to the RUN position.

Is the SERVICE ENGINE SOON indicator on?

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Go to Step 2

Go to Instrument Cluster Indicators and Gauges Inoperative

2

  1. Disconnect the engine oil pressure indicator switch connector.
  2. Connect a (3 amp) fused jumper between the engine oil pressure indicator switch connector terminal A and ground.
  3. Turn the ignition switch to the RUN position.

Is the Oil Pressure warning indicator on?

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Go to Step 3

Go to Step 4

3

  1. Check for a poor connection at the engine oil pressure indicator switch connector.
  2. If OK, replace the engine oil pressure switch. Refer to Engine Oil Pressure Sensor and/or Switch Replacement in Engine Mechanical.

Has the repair been made and the system rechecked?

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System OK

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4

Check for a poor connection or open in circuit 31 between the instrument cluster harness connector C1 terminal A and the engine oil pressure indicator switch harness connector terminal A.

Is there a poor connection or open in circuit 31?

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Go to Step 5

Go to Step 6

5

Repair the poor connection or open in circuit 31.

Has the repair been made and the system rechecked?

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System OK

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6

  1. Check the oil pressure warning indicator bulb and bulb connection.
  2. If OK, replace the instrument cluster. Refer to Instrument Cluster Replacement .

Has the repair been made and the system rechecked?

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System OK

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