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. Not all control modules listed will be applicable to all vehicles. Refer to the schematics to determine which control modules apply. 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
Battery Energy Control Module	High Speed GMLAN Powertrain Expansion Bus	Scan Tool Does Not Communicate with High Speed GMLAN Device DTC U0074 (Mid Speed or Chassis Expansion Bus) , DTC U0074 (Powertrain Expansion Bus)
Body Control Module	High Speed GMLAN Low Speed GMLAN Local Interconnect Network (LIN)	Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U1500-U15BF
Compass Module	Local Interconnect Network (LIN)	DTC U1500-U15BF
Electronic Brake Control Module	High Speed GMLAN Chassis High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device
Engine Control Module	High Speed GMLAN Powertrain Expansion Bus	Scan Tool Does Not Communicate with High Speed GMLAN Device DTC U0074 (Mid Speed or Chassis Expansion Bus) , DTC U0074 (Powertrain Expansion Bus)
Fuel Pump Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Headlamp Horizontal Motor - Left	Local Interconnect Network (LIN)	DTC U1500-U15BF
Headlamp Horizontal Motor - Right	Local Interconnect Network (LIN)	DTC U1500-U15BF
Headlamp Control Module	High Speed GMLAN Local Interconnect Network (LIN)	Scan Tool Does Not Communicate with High Speed GMLAN Device DTC U1500-U15BF
Head-Up Display	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
HVAC Control Module	Low Speed GMLAN Local Interconnect Network (LIN)	Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U1500-U15BF
Immobilizer Control Module	Local Interconnect Network (LIN)	DTC U1500-U15BF
Inflatable Restraint Sensing and Diagnostic Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Info Display Module	Local Interconnect Network (LIN)	DTC U1500-U15BF
Instrument Cluster	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
Multi-axis Acceleration Sensor	Chassis High Speed GMLAN	Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device
Multimedia Player Interface Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Outside Rearview Mirror Switch	Local Interconnect Network (LIN)	DTC U1500-U15BF
Parking Brake Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Passenger Presence Detection Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Power Steering Control 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 Controls	Local Interconnect Network (LIN)	DTC U1500-U15BF
Rear Differential Clutch Control Module	High Speed GMLAN Chassis High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device
Rear Parking Assist Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Seat Heating Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
Seat Memory Control Module	Low Speed GMLAN Local Interconnect Network (LIN)	Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U1500-U15BF
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
Starter/Generator Control Module	High Speed GMLAN Powertrain Expansion Bus	Scan Tool Does Not Communicate with High Speed GMLAN Device DTC U0074 (Mid Speed or Chassis Expansion Bus) , DTC U0074 (Powertrain Expansion Bus) (Powertrain Expansion Bus)
Steering Wheel Angle Sensor	Chassis High Speed GMLAN	Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device
Sunroof Control Module	Local Interconnect Network (LIN)	DTC U1500-U15BF
Sunroof Sunshade Motor Module	Local Interconnect Network (LIN)	DTC U1500-U15BF
Suspension Control Module	High Speed GMLAN Chassis High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device
Telematics Communication Interface Control Module	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
Transmission Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
Transmission Shift Lever Position Indicator	Local Interconnect Network (LIN)	DTC U1500-U15BF
Window Motor - Driver	Local Interconnect Network (LIN)	DTC U1500-U15BF
Window Motor - Passenger	Local Interconnect Network (LIN)	DTC U1500-U15BF
Window Switch - Driver	Local Interconnect Network (LIN)	DTC U1500-U15BF
Window Switch - Left Rear	Local Interconnect Network (LIN)	DTC U1500-U15BF
Window Switch - Passenger	Local Interconnect Network (LIN)	DTC U1500-U15BF
Window Switch - Right Rear	Local Interconnect Network (LIN)	DTC U1500-U15BF