GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Turn the ignition switch to the RUN position.
  2. Disconnect the engine coolant temperature (ECT) sensor.

Does the temperature gauge move to COLD?

--

Go to Step 2

Go to Step 3

2

Replace the engine coolant temperature sensor. Refer to Engine Coolant Temperature Sensor Replacement , Engine Coolant Temperature Sensor Replacement 5.7L, Engine Coolant Temperature Sensor Replacement 6.5L (L57), Engine Coolant Temperature Sensor Replacement 6.5L (L65), or Engine Coolant Temperature Sensor Replacement 7.4L in Engine Controls.

Is the repair complete?

--

System OK

--

3

Using a test light, backprobe the instrument cluster connector from cavity 13 to B +.

Did the test light illuminate?

--

Go to Step 4

Go to Step 5

4

Repair the short to ground in CKT 35 (DK GRN) between the instrument cluster connector, cavity 13 and the ECT sensor connector, cavity A.

Is the repair complete?

--

System OK

--

5

Using a test light, backprobe the instrument cluster from cavity 31 to B +.

Does the test light illuminate?

--

Go to Step 7

Go to Step 6

6

Repair the open in CKT 451 (BLK/WHT) between the instrument cluster connector, cavity 31 and G 108.

Is the repair complete?

--

System OK

--

7

Replace the instrument cluster.

Is the repair complete?

--

System OK

--