Test Description

The numbers below refer to the step numbers in the test procedure.

1. 4)  - Lack of communication may be because of 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. 5)  - The SYMPTOM LIST  will determine the correct diagnostic procedure to use.
3. 6)  - The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will collect all the available information before you perform tests.