GM Service Manual Online
For 1990-2009 cars only

Engine Coolant Temperature Gage Inaccurate or Inoperative 1

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

Inspect the system.

Are any instrument cluster DTCs stored in memory?

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Go to Diagnostic Trouble Code (DTC) List/Type

Go to Step 3

3

  1. Install a scan tool.
  2. Turn the ignition switch to the RUN position.
  3. Select the temperature gauge sweep test under the output control menu.

Does the temperature gauge perform a full sweep when commanded?

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Go to Powertrain On Board Diagnostic (OBD) System Check (RPO 3.1L) or Powertrain On Board Diagnostic (OBD) System Check (RPO 3.8L) in Engine Controls

Go to Step 4

4

  1. Replace the instrument cluster. Refer to Instrument Cluster Replacement .
  2. Inspect the system.

Is the repair complete?

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Go to Diagnostic System Check - Instrument Cluster

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