RAM 3500 Van V8-5.9L VIN Z LDC (1998)
Body Control Module: Description and Operation
System Description and Functional Operation
The body system on the 1998 AB HIGH LINE consists of three modules that communicate over the CCD bus (Chrysler Collision Detection multiplex
system). There are two additional modules, the Powertrain Control Module (PCM) and the Controller Anti-Lock Brake (CAB) that are not part of the
body system, but do utilize the CCD bus for communication. The CAB also utilizes the bus for diagnostics. The PCM sends and receives messages on
the CCD bus, however diagnostics are performed through the Serial Communication Interface of SCI, the same as previous years. All of the information
about the functioning of all the system is organized, controlled, and communicated by the CCD bus, which is described in Section 3 (CCD Bus) of this
general information section.
Through the CCD bus, information about the operation of vehicle components and circuits is relayed quickly to the appropriate module(s). All modules
receive all the information transmitted on the bus even though a module may not require all the information to perform it's function. It will only respond
to messages "addressed" to it through a binary coding process. This method of data transmission significantly reduces the complexity of the wiring in the
vehicle and the size of wiring harnesses.
