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?

--

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 in Instrument Panel, Gauges and Console.

Has the repair been made and the system rechecked?

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System OK

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