CCD Bus Circuit Operation

CCD BUS OPERATION
Various modules exchange information through a communications port called the CCD Bus. The powertrain control module (PCM) transmits the Malfunction Indicator Lamp (Check Engine) On/Off signal and engine RPM on the CCD Bus. The PCM receives the Air Conditioning elect input, transaxle gear position input and speed control engage inputs over the CCD Bus. The PCM also receives the air conditioning evaporator temperature signal from the CCD Bus.

The bus wires are a twisted pair. There are two different circuits used for the bus.

The positive side of the bus wire is accomplished on the D1 circuit, and the negative is on the D2 circuit.`

The following components access or send information on the CCD Bus.
- Instrument Panel
- Body Control Module
- Air Bag System Diagnostic Module
- Full A/C Display Head
- ABS Module
- Transmission Control Module
- Powertrain Control Module
- Overhead Travel Module

CIRCUIT OPERATION
The CCD Bus is used to supply all of the communications between the Body Control Module (BCM) and the instrument cluster. The bus wires are a twisted pair. There are two different circuits used for the bus.

The positive side of the bus wire is accomplished on the D1 circuit. and the negative is on the D2 circuit.