GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Instrument Cluster Schematics

Connector End View Reference: Instrument Panel, Gages, and Console Connector End Views

1

Did you perform the Instrument Cluster Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

  1. Install a scan tool.
  2. Start the engine.
  3. With the scan tool, observe the Engine Speed parameter in the IPC Data 1 data list.

Does the Engine Speed parameter match the tachometer display?

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

Go to Step 3

3

Test the engine speed signal circuit for a high resistance between the IPC and PCM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 6

Go to Step 4

4

Inspect for poor connections at the harness connector of the instrument cluster. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 6

Go to Step 5

5

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

Go to Step 6

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6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2