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Circuit Operation

There are two data lines that can be accessed with a scan tool. The UART data line (800 CKT) allows the scan tool (when connected), Powertrain Control Module, (PCM) Instrument Cluster (I/P), Diagnostic Energy Reserve Module (DERM), and the Electronic Brake Control Module (EBCM) to communicate via serial data. The OBDII data line (1807 CKT) allows a scan tool to directly access the Powertrain Control Module to read emissions related information. A scan tool can gain access to both data lines through the Data Link Connector (DLC). System operations can then be monitored or controlled for diagnostic purposes.