Data Link References

WARNING: This page is about a different car, the 2005 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

This table identifies which serial data link that a particular module uses for in-vehicle data transmission. Some modules may use more than one data link to communicate. This table is used to assist in correcting a communication malfunction between the control module and the scan tool. For the description and operation of these serial data communication circuits, refer to Data Link Communications Description and Operation .

Control Module	Data Link Type	Diagnostic Procedure
Schematic Reference: Data Link Connector (DLC) Schematics
Audio Amplifier (AMP)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Dash Integration Module (DIM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Digital Radio Receiver (DRR), w/U2K	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Driver Door Module (DDM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Driver Door Switch Assembly (DDSA)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Electronic Brake Control Module (EBCM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Engine/Powertrain Control Module (ECM/PCM)	Class 2 (LS6, LY7, LP1) High Speed GMLAN (LY7, LP1)	Refer to: Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD) (LS6) Scan Tool Does Not Communicate with High Speed GMLAN Device (LY7, LP1)
Front Passenger Door Module (FPDM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Instrument Panel Cluster (IPC)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Inflatable Restraint Sensing and Diagnostic Module (SDM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Headlamp - Left, w/TR7	Keyword 2000	Refer to Scan Tool Does Not Communicate with Keyword Data Line
Headlamp - Right, w/TR7	Keyword 2000	Refer to Scan Tool Does Not Communicate with Keyword Data Line
HVAC Control Module	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Left Rear Door Module (LRDM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Memory Seat Module (MSM), w/A45	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Radio	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Radio Antenna Module	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Rear Integration Module (RIM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Right Rear Door Module (RRDM)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Transmission Control Module (TCM), w/M82	High Speed GMLAN	Refer to Scan Tool Does Not Communicate with High Speed GMLAN Device
Theft Deterrent Control Module (VTD)	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
TV Antenna Module, wU2Y	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)
Vehicle Communication Interface Module (VCIM), w/UE1	Class 2	Refer to Scan Tool Does Not Communicate with Class 2 Device (LHD) or Scan Tool Does Not Communicate with Class 2 Device (RHD)