GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Did you perform the Engine Cooling Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Engine Cooling

2

Start the engine.

Does the hot coolant indicator illuminate?

Go to Step 3

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

3

  1. Install a scan tool.
  2. Select instrument panel cluster (IPC) inputs Menu.

Does the scan tool indicate that the Coolant Hot Lamp is ON?

Go to Engine Overheating

Go to Step 4

4

Test the hot coolant indicator control circuit from the PCM to the IPC for a short to ground.

Did you find and correct the condition?

Go to Step 6

Go to Step 5

5

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

Did you complete the repair?

Go to Step 6

--

6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2