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Information Bus: Description and Operation

[1][2]DATA LINK COMMUNICATIONS DESCRIPTION AND OPERATION

CLASS 2 SERIAL DATA
The Class 2 serial data link allows modules to transmit, receive, or exchange data:
^ Electronic Climate Control Module (ECCM)
^ Transfer Case Shift Control Module (TCSCM)
^ Electronic Brake Control Module (EBCM)
^ Powertrain Control Module (PCM)
^ Vehicle Interface Unit (VIU)
^ Body Control Module (BCM)
^ Instrument Panel Cluster (IPC)
^ Driver Information Center (DIC)
^ Memory Seat Module (MSM)
^ Inflatable Restraint Sensing And Diagnostic Module (SDM)

The Class 2 serial data link allows a scan tool to communicate with these modules for testing purposes, checking for DTCs, and to activate/enable/disable functions. These communication circuits are bussed together via SP201 which ensures a connection between the Class 2 communication circuits.

The data link connector has a signal return circuit for the serial data signal exiting the scan tool.

The scan tool is also supplied battery positive voltage and ground at the DLC.