Class 2 Data Line

Class 2 communication system is used for most vehicle system controllers that exchange data and commands. Class 2 data is pulse width modulated and prioritized. This allows better utilization of data line and ensures messages of higher priority override messages of lesser importance. Control modules on the class 2 serial data circuit are:

• Body Control Module (BCM).
• Cellular telephone.
• Radio receiver.
• Integrated Radio Chassis (IRC).
• CD player.
• OnStar(R) Vehicle Integration Unit (VIU).