Data Link Connector: Description and Operation

You may access 2 data lines with the scan tool. The serial data line UART (circuit 800) allows the following components to communicate via serial data:
^ The scan tool
^ The powertrain control module (PCM)
^ The instrument panel cluster
^ The sensing diagnostic module (SDM)
^ The electronic brake control module (EBCM)

The serial data line class 2 (circuit 1807) allows the scan tool to access directly the PCM in order to read emissions-related information. The scan tool gains access to both data lines through the data link connector (DLC). You may then monitor or control system operations for diagnostic purposes.