Chassis High Speed GMLAN Circuit Description
WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
The high speed GMLAN chassis expansion bus functions the same as the high speed GMLAN bus, and the two buses operate in parallel. The expansion chassis bus was added to reduce message congestion on the primary high speed bus. Since the high speed GMLAN chassis bus and primary high speed GMLAN bus operate in the same manner, the diagnostics for each are the same.