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Test Description

WARNING: This page is about a different car, the 2004 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

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

  1. 2:  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.
  2. 3:  The symptoms list in Symptoms will determine the correct diagnostic procedure to use.
  3. 4:  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.
Diagnostic System Check - Remote Keyless Entry

Step Action Yes No
Schematic Reference: Keyless Entry Schematics 
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. Attempt to establish communication with the following modules:
    • Driver's Door Module (DDM)
    • Passenger
    • Left Rear Door Module (LRDM)
    • Right Rear Door Module (RRDM)
    • The Dash Integration Module (DIM)
    • The Instrument Panel Cluster (IPC)
    • The Rear Integration Module (RIM)
    • The Radio Antenna module
Does the scan tool communicate with all of the listed modules?		 Go to Step 3  Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications
3  Select the display DTC function on the scan tool for the following modules:
  • Driver's Door Module (DDM)
  • Passenger
  • Left Rear Door Module (LRDM)
  • Right Rear Door Module (RRDM)
  • The Dash Integration Module (DIM)
  • The Instrument Panel Cluster (IPC)
  • The Rear Integration Module (RIM)
  • The Radio Antenna module

Does the scan tool display any DTCs?		 Go to Step 4  Go to Symptoms - Keyless Entry 
4  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 Go to Step 5 
5 Does the scan tool display DTC B1000, B1001, B1004, B1007, B1009, B1013, or B1014? Go to Diagnostic Trouble Code (DTC) List in Body Control System Go to Step 6 
6 Does the scan tool display DTC B1327 or B1328? Go to Diagnostic Trouble Code (DTC) List in Engine Electrical Go to Symptoms - Keyless Entry 
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