GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Check the vehicle for Diagnostic Trouble Codes (DTCs).

Are any DTCs present?

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Go to Diagnostic Trouble Code (DTC) List in Engine Controls

Go to Step 2

2

  1. Disconnect the Powertrain Control Module (PCM) connector C2.
  2. Turn the ignition switch to the RUN position.

Is the SERVICE ENGINE SOON indicator on?

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Go to Step 3

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls

3

  1. Check for a short to ground in circuit 419.
  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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