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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 .

Reference Information 

Schematic Reference: Data Communication Schematics

Code Device Data Link Type Diagnostic Procedure
A11 Radio
  • Gateway Isolated Low Speed GMLAN
  • MOST Bus
  • Local Interconnect Network (LIN)
A26 HVAC Controls
  • Low Speed GMLAN
  • Local Interconnect Network (LIN)
A34 HVAC Controls - Auxiliary Local Interconnect Network (LIN) DTC U1500-U15FF 
B110 Battery Sensor Module Local Interconnect Network (LIN) DTC U1500-U15FF 
B165 Content Theft Deterrent Sensor Module Local Interconnect Network (LIN) DTC U1500-U15FF 
B174W Frontview Camera - Windshield
  • High Speed GMLAN
  • Low Speed GMLAN
  • Object High Speed GMLAN
B200 Rain Sensor Module Local Interconnect Network (LIN) DTC U1500-U15FF 
B218L Side Object Sensor Module - Left Low Speed GMLAN Scan Tool Does Not Communicate with Low Speed GMLAN Device 
B233B Radar Sensor Module - Long Range Object High Speed GMLAN DTC U0075 
B233LF Radar Sensor Module - Short Range Left Front Object High Speed GMLAN DTC U0075 
B233R Radar Sensor Module - Short Range Rear Object High Speed GMLAN DTC U0075 
B233RF Radar Sensor Module - Short Range Right Front Object High Speed GMLAN DTC U0075 
E13LA Headlamp Assembly - Left Local Interconnect Network (LIN) DTC U1500-U15FF 
E13RA Headlamp Assembly - Right Local Interconnect Network (LIN) DTC U1500-U15FF 
K9 Body Control Module
  • High Speed GMLAN
  • Low Speed GMLAN
  • Local Interconnect Network (LIN)
K17 Electronic Brake Control Module
  • High Speed GMLAN
  • Chassis High Speed GMLAN
K19 Suspension Control Module
  • High Speed GMLAN
  • Chassis High Speed GMLAN
K20 Engine Control Module
  • High Speed GMLAN
  • Powertrain High Speed GMLAN
  • Local Interconnect Network (LIN)
K28 Headlamp Leveling Control Module
  • Gateway Expansion High Speed GMLAN
  • Local Interconnect Network (LIN)
K29 Seat Heating Control Module Local Interconnect Network (LIN) DTC U1500-U15FF 
K29R Seat Heating Control Module - Rear Local Interconnect Network (LIN) DTC U1500-U15FF 
K33 HVAC Control Module
  • Low Speed GMLAN
  • Local Interconnect Network (LIN)
K36 Inflatable Restraint Sensing and Diagnostic Module
  • Chassis High Speed GMLAN
  • Low Speed GMLAN
K38 Chassis Control Module
  • High Speed GMLAN
  • Chassis High Speed GMLAN
  • Local Interconnect Network (LIN)
K39 Liftgate Control Module
  • Low Speed GMLAN
  • Local Interconnect Network (LIN)
K40 Seat Memory Control Module
  • Low Speed GMLAN
  • Local Interconnect Network (LIN)
K43 Power Steering Control Module
  • High Speed GMLAN
  • Chassis High Speed GMLAN
K47 Rear Differential Clutch Control Module
  • High Speed GMLAN
  • Chassis High Speed GMLAN
K56 Serial Data Gateway Module
  • Gateway Expansion High Speed GMLAN
  • Gateway Isolated High Speed GMLAN
  • High Speed GMLAN
  • Gateway Isolated Low Speed GMLAN
  • Low Speed GMLAN
  • Chassis High Speed GMLAN
K60 Steering Column Lock Module Low Speed GMLAN Scan Tool Does Not Communicate with Low Speed GMLAN Device 
K68 Trailer Lighting Control 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
K74 Human Machine Interface Control Module
  • Gateway Isolated High Speed GMLAN
  • MOST Bus
  • Local Interconnect Network (LIN)
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 
K89 Immobilizer Control Module Local Interconnect Network (LIN) DTC U1500-U15FF 
K99 Steering Column Position Control Module Local Interconnect Network (LIN) DTC U1500-U15FF 
K111 Fuel Pump Driver Control Module Powertrain High Speed GMLAN DTC U0074 
K124 Active Safety Control Module
  • Gateway Expansion High Speed GMLAN
  • Low Speed GMLAN
  • Object High Speed GMLAN
  • Chassis High Speed GMLAN
K157 Video Processing Control Module Gateway Isolated Low Speed GMLAN DTC U007D 
K171 Hands-Free Liftgate Sensor Control Module Local Interconnect Network (LIN) DTC U1500-U15FF 
K173 Transmission Range Control Module
  • High Speed GMLAN
  • Chassis High Speed GMLAN
  • Local Interconnect Network (LIN)
K182 Parking Assist Control Module
  • Chassis High Speed GMLAN
  • Low Speed GMLAN
M35D Window Motor Module - Driver Local Interconnect Network (LIN) DTC U1500-U15FF 
M35P Window Motor Module - Passenger Local Interconnect Network (LIN) DTC U1500-U15FF 
M69 Sunroof Motor Local Interconnect Network (LIN) DTC U1500-U15FF 
M101L Seat Belt Retractor Motor Module - Left Chassis High Speed GMLAN DTC U0077 
M101R Seat Belt Retractor Motor Module - Right Chassis High Speed GMLAN DTC U0077 
P16 Instrument Cluster
  • Gateway Isolated Low Speed GMLAN
  • MOST Bus
  • Local Interconnect Network (LIN)
P17 Info Display Module
  • Gateway Isolated Low Speed GMLAN
  • Local Interconnect Network (LIN)
P25 Power Sounder Content Theft Deterrent Alarm Module Local Interconnect Network (LIN) DTC U1500-U15FF 
P29 Head-Up Display Local Interconnect Network (LIN) DTC U1500-U15FF 
S3 Transmission Shift Lever Local Interconnect Network (LIN) DTC U1500-U15FF 
S70D Steering Wheel Controls Switch - Right Upper Local Interconnect Network (LIN) DTC U1500-U15FF 
S79D Window Switch - Driver Local Interconnect Network (LIN) DTC U1500-U15FF 
S79LR Window Switch - Left Rear Local Interconnect Network (LIN) DTC U1500-U15FF 
S79P Window Switch - Passenger Local Interconnect Network (LIN) DTC U1500-U15FF 
S79RR Window Switch - Right Rear Local Interconnect Network (LIN) DTC U1500-U15FF 
T3 Audio Amplifier
  • Gateway Isolated Low Speed GMLAN
  • MOST Bus
T19 Power Supply Transformer Powertrain High Speed GMLAN DTC U0074