Data Link References

This table identifies which serial data link that a particular control module uses for in-vehicle data transmission. Some control modules may use more than one data link to communicate. Some control modules may have multiple communication circuits passing through them without actively communicating on that data link. This table is used to assist in correcting a communication malfunction. 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 Communication Schematics
Audio Amplifier	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Auxiliary Body Control Module (XBCM)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Body Control Module (BCM)	High Speed GMLAN Low Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Low Speed GMLAN Device
Door Lock/Window Switch - Driver	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Door Lock/Window Switch - Passenger	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Electronic Brake Control Module (EBCM)	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Electronic Compass Module	Local Interconnect Network (LIN)	DTC U1500, U1511, U1512, or U1513
Electronic Suspension Control (ESC) Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Engine Control Module (ECM)	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Fuel Pump Flow Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Headlamp Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
HVAC Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Inflatable Restraint Sensing and Diagnostic Module (SDM)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Inflatable Restraint Front Passenger Presence System (PPS) Sensor	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Inside Rearview Mirror (ISRVM)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Instrument Panel Cluster (IPC)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Keyless Entry Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Liftgate Module (LGM)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Memory Seat Module (MSM)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Parking Brake Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Pedestrian Impact Detection Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Radio	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Radio/HVAC Control	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Rear Object Sensor Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Remote Control Door Lock Receiver (RCDLR)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Side Object Sensor - Left	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Side Object Sensor - Right	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Theft Deterrent Module (TDM)	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Transfer Case Shift Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Transmission Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Vehicle Communication Interface Module (VCIM)	High Speed GMLAN Low Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Low Speed GMLAN Device
Window Motor - Driver	Local Interconnect Network (LIN)	DTC U1500, U1511, U1512, or U1513
Window Motor - Passenger	Local Interconnect Network (LIN)	DTC U1500, U1511, U1512, or U1513