Data Link Connector (DLC)
The DLC is a standardized 16 way connector located below the instrument panel
and close to the steering column. Both the connector design and location are dictated
by industry wide agreements. All DLC's are required to provide a B+ at all times
to Pin 16. This positive supply is used to power the scan tool. All DLC's supply
a power ground at Pin 4 and a clean signal ground at Pin 5. The Class 2 serial data
circuit is provided at pin 2 of the DLC.
Class 2 Serial Data Link
The class 2 serial data link in this vehicle is configured in a star which
means, there is no redundant path for the serial data to flow through, in the event
that the conductor feeding a modules branch develops an open condition
that module will not be able to communicate. The following modules use the Data
Link network to communicate with each other:
• | The body control module (BCM) |
• | The electronic brake control module (EBCM) |
• | The powertrain control module (PCM) |
• | The inflatable restraint sensing and diagnostic module (SDM) |
• | The vehicle theft deterrent (VTD) |
The class 2 serial data link allows a scan tool to communicate with
the above modules for diagnostic and testing purposes.