A Diagnostic System Check - Power Door Systems

Steps 1 - 4:

Step 5:

Test Description
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 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.
3. This step determines if a Body Control Module (BCM) DTC based diagnostic path or a symptom based diagnostic path are to be followed.
4. 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.
5. This step determines if a total ECU failure exists or displays stored system related DTCs to be diagnosed.