Test Description

WARNING: This page is about a different car, the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, and 2002 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table:

2. Lack of communication with the PCM may be due to a partial or total malfunction of the class 2 serial data circuit. Lack of communication with the EBCM may be due to a malfunction of the UART serial data circuit. The specified procedure will determine the particular condition.
4. The presence of DTCs which begin with "U" indicate some other module is not communicating or that the EBCM is not communicating with the PCM on the class 2 serial data circuit. The specified procedure will compile all the available information before tests are performed.

Fig 1: Diagnostic System Check - ABS (1 Of 2)

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Fig 2: Diagnostic System Check - ABS (2 Of 2)

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Fig 3: Scan Tool Output Controls

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Fig 4: Scan Tool Data List

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