GM Service Manual Online
For 1990-2009 cars only

Class 2 Serial Data Link

The Class  2 serial data link allows these modules to communicate data with each other:

    â€¢ Body Control Module (BCM)
    â€¢ Driver Information Center (DIC)
    â€¢ Electronic Brake Control Module (EBCM)
    â€¢ Inflatable Restraint Sensing and Diagnostic Module (SDM)
    â€¢ Instrument Panel Cluster
    â€¢ Powertrain Control Module (PCM)
    â€¢ Radio

In addition, the Class 2 serial data link allows a scan tool to communicate with these modules for diagnostic and testing purposes. The Class 2 serial data link is located at the DLC connector.