The numbers below refer to the step numbers on the diagnostic table.
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.
The symptom list in Symptoms will determine the correct diagnostic procedure to use.
Step | Action | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|
1 | Install a scan tool. Does the scan tool power up? | Go to Step 2 | Go to Scan Tool Does Not Power Up in Data Link Communications | ||||||
Does the scan tool communicate with the control modules listed above? | Go to Step 3 | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | |||||||
Select the display DTC function on the scan tool for the following control modules:
Does the scan tool display any DTCs? | Go to Step 4 | ||||||||
4 | Does the scan tool display any DTCs that begin with a "U"? | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | Go to Step 5 | ||||||
5 | Does the scan tool display DTC B1652, B1656 or B1657? | Go to Diagnostic Trouble Code (DTC) List in Body Control Systems | Go to Step 6 | ||||||
6 | Does the scan tool display DTC B1982, B1983, P0560 or P0620? | Go to Diagnostic Trouble Code (DTC) List in Engine Electrical |