GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Instrument Cluster Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Verify the fault is present.

Does the system operate normally?

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

Go to Step 3

3

Important: There is a flat band in the gauge where the engine temp is between 190°F (88°C) and 220°F (104°C) and gauge stays at 200°F (93°C).

  1. With the scan tool, select instrument panel cluster, data display, and data.
  2. Turn ON the ignition, with the engine ON.
  3. Let the engine idle to normal operating temperature.
  4. Select the monitored Coolant Temp display on the scan tool.
  5. With the scan tool, observe the displayed monitored Temp parameter and observe the temperature gauge reading on the cluster.

Is the temperature on the scan tool and the temperature on the gauge approximately the same outside the flat band?

Approximately 200°F (93°C) @ steady state

Go to Step 4

Go to Step 5

4

  1. If the Monitored Coolant Temp is less than 100°F (38°C), the gauge should be at or near the lowest reading.
  2. If the Monitored Coolant Temp is greater than 260°F (127°C), the gauge should be at or near the maximum reading.

Does the gauge reading properly?

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

Go to Step 5

5

Replace the instrument cluster. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

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Go to Step 6

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6

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3