Data Link Connector: Description and Operation

CIRCUIT OPERATION
Circuit M1 supplies battery voltage to the universal data link connector. This circuit is protected by a 10 Amp fuse located in cavity 5 of the junction block. Circuit M1 is the Ignition-Off Draw circuit and supplies power to the Body Control Module (BCM), radio memory, interior lamps, and other components.

A twisted pair of wires, circuits D1 and D2, connect to the data link connector. These wires are connected to the CCD Bus. The CCD Bus is used for diagnosing vehicle components and modules.

Circuits D20 and D21 from the Powertrain Control Module (PCM) connect to the data link connector. Circuit D20 connects to cavity 75 of the PCM and is the SCI receive circuit. Circuit D21 connects to cavity 65 of the PCM and is the SCI transmit.

The D21 circuit is also spliced and connects to the Transmission Control Module (TCM), and the Controller Anti Lock Brakes (CAB), if equipped.

The D6 circuit is also connected to the universal data link connector. This circuit is used as a SCI line from the TCM.

The universal data link connector is also interfaced with the CCD Bus. Circuit D1 is used for CCD (+) and D2 is used for CCD (-).

There are also two grounds used for the universal data link connector. One is a power ground and one is a regular ground.