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:

    • The body control module (BCM)
    • The electronic brake control module (EBCM)
    • The instrument cluster
    • The powertrain control module (PCM)/vehicle control module (VCM)
    • The supplemental restraint sensing and diagnostic module (SDM)
    • The transfer case shift control module (TCSCM)

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.