Class 2 Serial Data Line

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Class 2 Serial Data Line
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

The class 2 serial data line on this vehicle is a star configuration. The following modules communicate on the class 2 serial data line:

  • The audio amplifier
  • The body control module (BCM)
  • The digital audio broadcast (DAB) module
  • The digital radio receiver
  • The driver door module (DDM)
  • The electronic brake control module (EBCM)
  • The front passenger door module (FPDM)
  • The HVAC control module
  • The HVAC control module-rear auxiliary
  • The inflatable restraint sensing and diagnostic module (SDM)
  • The instrument panel cluster (IPC)
  • The memory seat module (MSM)
  • The powertrain control module (PCM)
  • The radio
  • The rear seat audio (RSA) controller
  • The rear seat entertainment (RSE) assembly w/U42
  • The rear wheel steering control module
  • The remote playback device-CD player w/U1S
  • The suspension control module
  • The transfer case shift control module
  • The transmission control module (TCM) w/Allison Transmission
  • The theft deterrent control module
  • The vehicle communication interface module (VCIM) w/UE1

The class 2 serial data line allows a scan tool to communicate with these modules for testing purposes, checking for DTCs, and to activate/enable/disable functions. These class 2 serial data circuits are bussed together via splice packs and a data link connector (DLC):

  • SP205
  • SP206
  • SP207
  • DLC-connects the scan tool to the class 2 serial data circuits.

Refer to DATA LINK COMMUNICATIONS COMPONENT VIEWSΒ  for an illustrated view of the splice pack locations.

RENDER: 1.0x

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