Data Link References

This table identifies which serial data link that a particular device uses for in-vehicle data transmission. Some devices may use more than one data link to communicate. Some devices 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 devices listed will be applicable to all vehicles. Refer to the schematics to determine which devices apply. For the description and operation of these serial data communication circuits, refer to Data Link Communications Description and Operation .

Code	Device	Data Link Type	Diagnostic Procedure
Schematic Reference: Data Communication Wiring Schematics
A11	Radio	Gateway Isolated Low Speed GMLAN	DTC U007D
B99	Steering Wheel Angle Sensor	Chassis High Speed GMLAN	DTC U0077
B174W	Frontview Camera - Windshield	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
K9	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-U15FF
K17	Electronic Brake Control Module	High Speed GMLAN Chassis High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device DTC U0077
K20	Engine Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
K29	Seat Heating Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
K33	HVAC Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
K36	Inflatable Restraint Sensing and Diagnostic Module	Chassis High Speed GMLAN Low Speed GMLAN	DTC U0077 Scan Tool Does Not Communicate with Low Speed GMLAN Device
K38	Chassis Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
K43	Power Steering Control Module	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
K56	Serial Data Gateway Module	High Speed GMLAN Gateway Isolated High Speed GMLAN Low Speed GMLAN Gateway Isolated Low Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device DTC U007C Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U007D
K60	Steering Column Lock Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
K71 / Q8 / T12	Transmission Control Module / Control Solenoid Valve Assembly / Automatic Transmission Assembly	High Speed GMLAN	Scan Tool Does Not Communicate with High Speed GMLAN Device
K73	Telematics Communication Interface Control Module	Gateway Isolated High Speed GMLAN Gateway Isolated Low Speed GMLAN	DTC U007C DTC U007D
K84	Keyless Entry Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
K85	Passenger Presence Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
K182	Parking Assist Control Module	Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device
M74D	Window Motor - Driver	Local Interconnect Network (LIN)	DTC U1500-U15FF
M74P	Window Motor - Passenger	Local Interconnect Network (LIN)	DTC U1500-U15FF
P16	Instrument Cluster	Low Speed GMLAN Gateway Isolated Low Speed GMLAN	Scan Tool Does Not Communicate with Low Speed GMLAN Device DTC U007D
S79LR	Window Switch - Left Rear	Local Interconnect Network (LIN)	DTC U1500-U15FF
S79RR	Window Switch - Right Rear	Local Interconnect Network (LIN)	DTC U1500-U15FF