Circuit Operation

There are two data lines that can be accessed by a scan tool. The Electronic Brake Control Module (EBCM) (if equipped) and the Sensing And Diagnostic Module (SDM) are accessed through the PPL/WHT wire at the Data Link Connector - On Board Diagnostics II (DLC-OBD II) at cavity 9. The Powertrain Control Module (PCM) is accessed through the PPL/GRN wire at the DLC-OBD II at cavity 7.

These communication lines are used to monitor the modules for diagnostic purposes and to check for Diagnostic Trouble Codes (DTCs). Voltage is applied at all times to the DLC-OBD II through the TAIL DOME fuse. The DLC-OBD II is permanently grounded to G202 (body ground) and G103 (engine ground).