GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Silverado - 4WD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Data Link References

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. Some 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

Body Control Module (BCM)
    • High Speed GMLAN
    • Low Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Communication Interface Module (OnStar), w/UE1
    • High Speed GMLAN - pass through only
    • Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Chime Module w/UL5

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Digital Radio Receiver (DRR), w/U2K

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Driver Door Switch (DDS)
    • Low Speed GMLAN
    • Local Interconnect
    • Network (LIN)

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 Suspension Control Module (ESCM), F45, F55

High Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Engine/Powertrain Control Module (ECM/PCM)

High Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Front and Rear Object Alarm Module

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Fuel Pump Control Module (FPCM)

High Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Glow Plug Control Module (GPCM)

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

Inside Rearview Mirror

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

Inflatable Restraint Sensing and Diagnostic Module (SDM)

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Inflatable Restraint Roll Over Sensor (ROS) w/ASF

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Memory Seat Module (MSM)/Driver Position Module (DPM)

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Passenger Door Switch (PDS)
    • Low Speed GMLAN
    • Local Interconnect
    • Network (LIN)

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Passenger Presence System (PPS)

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Power Take Off Module (PTO)

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

Rear Seat Audio (RSA) w/UK6

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device

Remote Control Door Lock Receiver (RCDLR) w/AP3, AP8

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

Trailer Brake Control Module (TBCM)

High Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Transfer Case Control Module (TCCM) w/NP8, NR3, NQH, NQF, NGQ

High Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Transmission Control Module (TCM)

High Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Ultrasonic Parking Aid (UPA) Module w/UD7

Low Speed GMLAN

Scan Tool Does Not Communicate with Low Speed GMLAN Device