The number(s) below refer to the step number(s) on the diagnostic table.
Enabling the headlamps in this step verifies that a door module is not using an alternate path to ground through the switch illumination circuit.
Lack of communication may be due to a partial or 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.
The presence of DTCs U1161, U1162, U1163 or U1170 indicate one or more of the door modules is not communicating on the power door serial data circuits.
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.
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 listed modules? | Go to Step 4 | 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 | ||||
Select the display DTCs function on the scan tool. Does the scan tool display any DTCs? | Go to Step 5 | Go to Symptoms - Doors | |||||
Does the scan tool display DTCs U1161, U1162, U1163 or U1170? | Go to DTC U1161-U1163 or U1170 | 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 7 | |||||
7 | Does the scan tool display DTC B1000, B1004, B1007, or B1009? | Go to Diagnostic Trouble Code (DTC) List in Body Control System | Go to Step 8 | ||||
8 | Does the scan tool display DTC B1327 or B1328? | Go to Diagnostic Trouble Code (DTC) List in Engine Electrical | Go to Step 9 | ||||
9 | Does the scan tool display B0490? | Go to Diagnostic Trouble Code (DTC) List in HVAC-Automatic | Go to Step 10 | ||||
10 | Does the scan tool display B2757, B2762 or B2772? | Go to Diagnostic Trouble Code (DTC) List in Seats | Go to Step 11 | ||||
11 | Does the scan tool display any DTC that begin with a "P"? | Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 3.8 L |