CCD Bus Circuit

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Chrysler Collision Detection (CCD) bus circuit is a pair of twisted wires traveling from module-to-module receiving and delivering coded information. Code identifies message and its importance. When multiple messages attempt to access CCD bus at once, code assigns priority and ranking.

Twisted wires used by CCD bus system are called CCD bus plus (+) and CCD bus minus (-). Both wires carry approximately 2.5 volts. Network consists of some modules with "bias" and some with "termination".

Bias is part of voltage divider network which places both bus positive and bus negative at 2.5 volts. Termination is part of circuitry required to complete voltage divider network and also provide some electromagnetic protection for CCD bus. All CCD termination applications have approximately 120 ohms resistance.