GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Engine Cooling Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check

2

Start the engine.

Does the ENGINE OVERHEATED message illuminate?

--

Go to Step 3

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

3

  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool select instrument panel cluster, then data, and observe the monitored coolant temperature.

Is the monitored coolant temperature an accurate representation of the engine temperature gauge?

--

Go to Step 4

Go to Engine Coolant Temperature Gage Inaccurate or Inoperative in Instrument Panel, Gauges and Console

4

With a scan tool select instrument panel cluster, and command the engine overheated message ON and OFF.

Does the ENGINE OVERHEATED message turn ON and OFF when commanded?

--

Go to Engine Overheating

Go to Step 5

5

Replace the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.

Is the replacement complete?

--

Go to Step 6

--

6

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3