Test Description

WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

The number(s) below refer to the step number(s) on the diagnostic table.

2. Lack of communication may be due to a partial malfunction or a total malfunction of the class 2 serial data circuit. The specified procedure will determine the condition.
5. The presence of DTCs which begin with "U" indicate some other system control module is not communicating.

Fig 1: Identifying Diagnostic System Check - Cellular Communication Diagnostic Table
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