Circuit Operation

There are two data lines that can be accessed with a scan tool. The 800 circuit data line (CLASS 1) is the Powertrain Control Module (PCM) Data Line. It allows the PCM, Electronic Brake Control Module (EBCM) (if equipped), and the Diagnostic Energy Reserve Module (DERM) to communicate by transmitting data through CKT 800. The other data line (CLASS 2) is CKT 1807 which also allows the PCM to communicate.

A scan tool can be connected to the Data Link Connector (DLC); this allows the scan tool to communicate with the PCM Data Line. System operations can then be monitored for diagnostic purposes.