GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Disconnect the powertrain control module (PCM) connector C1.
  2. Turn the ignition switch to the RUN position.

Does the coolant temperature warning indicator light?

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Go to Step 2

Go to Step 3

2

  1. Repair the short to ground in CKT 35.
  2. Inspect the system.

Is the repair complete?

--

System OK

--

3

  1. Turn the ignition switch to RUN position.
  2. Connect a fused 3 amp jumper between the PCM harness and ground.

Does the coolant temperature warning indicator light?

--

Go to Step 4

Go to Step 5

4

  1. Replace the powertrain control module. Refer to one of the following procedures:
  2. •  Powertrain Control Module Replacement/Programming in Engine Controls - 3.1L (LG8)
  3. Inspect the system.

Is the repair complete?

--

System OK

--

5

  1. Inspect for a poor connection or an open in CKT 35 between the instrument cluster harness connector C1 terminal 75.
  2. If the connection is OK, replace the instrument cluster. Refer to Instrument Cluster Replacement .
  3. Inspect the system.

Is the repair complete?

--

System OK

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