GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Start the vehicle.

Does the engine coolant temperature gauge read hot with the engine cold?

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

Go to Step 3

3

  1. Connect a scan tool to the vehicle data link connector (DLC).
  2. Using the scan tool, attempt to perform the engine coolant temperature gage sweep test.

Does the engine coolant temperature gage sweep from cold to hot and return to cold?

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Go to Powertrain On Board Diagnostic (OBD) System Check (3.8L) or Powertrain On Board Diagnostic (OBD) System Check (5.7L)

Go to Step 4

4

Replace the instrument cluster. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

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Go to Step 5

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5

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3