GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 DeVille 🢒 Body and Accessories 🢒 Body Control System 🢒 Diagnostic System Check - Door Systems

Test Description

The Number(s) below refer to the step number(s) on the diagnostic table.

  1. 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.

    2.

  2. The symptom list in Symptoms will determine the correct diagnostic procedure to use.

    3.

  3. 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.

    4.

  4. 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

2

  1. Turn ON the ignition, with the engine OFF.
  2. Turn ON the headlamp switch.
  3. Attempt to establish communication with the following modules:
    4. • All door modules (DDM, PFDM, LMDM, RMDM, LRDM, RRDM)
    • Driver Door Switch Assembly (DDSA)
    • Instrument Panel Cluster (IPC)
    • Memory Seat Module (MSM)
    • Powertrain Control Module (PCM)
    • Rear Integration Module (RIM)
    • Remote Function Actuator (RFA)

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 Lin 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.

  1. Access the Class 2 Power Mode in the Diagnostic Circuit Check on the scan tool.
  2. Rotate the ignition switch through all positions while observing the ignition switch power mode parameter.

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

4

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 Diagnostic Trouble Code (DTC) List

Go to Step 6

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 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 Diagnostic Trouble Code (DTC) List