GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Did you review the Instrument Cluster Circuit Description and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Instrument Panel, Gages and Console

2

Verify that the engine coolant temperature (ECT) gauge is inoperative.

Does the ECT gauge operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Turn the ignition switch to LOCK.
  2. Disconnect the ECT sending unit connector.
  3. Connect the red lead from the J 33431-C

Does the ECT gauge indicate the appropriate readings within the specified values?

Go to Step 4

Go to Step 5

4

Replace the ECT sending unit.

Did you complete the repair?

Go to Step 10

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5

Test for a short to ground condition from the instrument cluster connector C3, cavity 4 and the ECT sending unit cavity 2.

Does a short to ground condition exist?

Go to Step 6

Go to Step 7

6

Repair the open in the YEL/WHT wire between the instrument panel cluster assembly and the ECT sending unit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

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7

Inspect for damage or loose connections in the instrument panel cluster printed circuit.

Does damage or loose connections exist?

Go to Step 8

Go to Step 9

8

Replace the instrument panel cluster printed circuit. Refer to Printed Instrument Cluster Circuit Replacement .

Did you complete the repair?

Go to Step 10

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9

Replace the ECT gauge. Refer to Fuel/Temperature Gage Replacement .

Did you complete the repair?

Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3