Test Description

The numbers below refer to the step numbers on the diagnostic table. See Fig 1.

1. 2
   
   Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
2. 4
   
   The Symptoms list in SYMPTOMS - INSTRUMENT PANEL, GAGES & CONSOLE  will determine the correct diagnostic procedure to use.
3. 5
   
   The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

Fig 1: Diagnostic System Check - Instrument Cluster (Steps 1-7)

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