Test Description
The numbers below refer to the step numbers on the diagnostic table.
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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.
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The symptom list in Symptoms will determine the correct diagnostic procedure to use.
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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.
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 | |||||||
3 | Attempt to communicate with the 4WAL 3 Sensor (EBCM). Does the scan tool communicate with the EBCM? | Go to Step 4 | Go to Scan Tool Does Not Communicate with Electronic Brake Control Module in Data Link Communications | ||||||
Select the display DTCs function on the scan tool for the following control modules:
Does the scan tool display any DTCs for the control modules listed above? | Go to Step 5 | ||||||||
Does the scan tool display any DTCs which begin with a "U"? | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications and to Scan Tool Does Not Communicate with Electronic Brake Control Module in Data Link Communications | Go to Step 6 | |||||||
6 | Does the scan tool display DTC B1000, B1004, or B1009? | Go to Diagnostic Trouble Code (DTC) List in Body Control Systems | Go to Step 7 | ||||||
7 | Does the scan tool display DTC P0562, P0563, P1637, or P1638? | Go to Diagnostic Trouble Code (DTC) List in Engine Electrical |
