CCD Bus
WARNING: This page is about a different car, the 1992 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
The CCD bus is a twisted pair of wires traveling from module to module receiving and delivering coded information. The code identifies the message and its importance. When multiple messages attempt to access CCD bus at once, code assigns priority ranking. The 2 twisted wires used by the CCD bus system are called Bus "+" and Bus "-". Both wires carry approximately 2.5 volts.