High Speed GMLAN Serial Data Line

The GMLAN serial data communications circuit on this vehicle is in a linear topology. The following modules are connected to the link, in order from data link connector (DLC) to the end of the linear configuration:

• The instrument panel module (IPM)
• The electronic suspension control (ESC) module, with F85
• The communication interface module (OnStar), with UE1
• The dynamic headlamp leveling (DHL) device, with TR7
• The electronic brake control module (EBCM)
• The transmission control module (TCM)
• The engine control module (ECM)

The distance sensing and cruise control (DSCC) module, with K59 option, it is connected to the high speed GMLAN bus through splice pack SP100. Refer to Data Communication Schematics  for more information.

The OnStar module doesn't functionally communicate on the high speed GMLAN bus. It is connected to high speed GMLAN bus for remotely diagnostic purposes.