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 a total malfunction of the class 2 serial data circuit, however, lack of communication may also be caused by an unpowered or ungrounded module. The specified procedure will determine the particular condition. Enabling the headlamps in this step verifies that a door module is not using an alternate path to ground through the switch illumination circuit, a condition which could cause the DTC or malfunction to be intermittent.
The symptom list in Symptoms will determine the correct diagnostic procedure to use.
The presence of other DTCs which begin with "U" indicate some other system control module is not communicating. The specified procedure will compile all the available information before tests are performed.
The presence of DTCs B1004, B1007, and B1009 indicate a module self diagnostic test has detected a malfunction. 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 all of the Modules? | Go to Step 3 | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | |||||||||||||||
3 |
Important: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode.
Does the ignition switch parameter reading match the ignition switch position for all switch positions? | Go to Step 4 | Go to Power Mode Mismatch in Body Control System | ||||||||||||||
With the scan tool, select the display DTCs function for each of the modules listed in step 2. Does the scan tool display any DTCs? | Go to Step 5 | Go to Symptoms - Doors | |||||||||||||||
5 | Does the scan tool display DTC U1713 or U1714? | Go to Step 6 | |||||||||||||||
Does the scan tool display any other DTCs which begin with a "U"? | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | Go to Step 6 | |||||||||||||||
Does the scan tool display DTC B1004, B1007, or B1009? | Go to Diagnostic Trouble Code (DTC) List in Body Control System | Go to Step 7 | |||||||||||||||
8 | Does the scan tool display DTC B1327 or B1328? | Go to Diagnostic Trouble Code (DTC) List in Engine Electrical |