Information Bus: Description and Operation

Data Link Communications Description and Operation

The scan tool accesses the following data lines:

- The brake pressure control valve (BPMV), on vehicles with antilock brake systems.
- The powertrain control module (PCM).
- The Inflatable Restraint Sensing and Diagnostic Control Module (SDM).

The BLU/RED wire at cavity 7 of the data link connector (DLC) OBD 2 provides access to the BPMV, SDM, and to the PCM. The RED/BLK wire at cavity 16 provides voltage to the scan tool. The WHT/BLK wire at cavity 4 and the BRN/RED wire at cavity 5 provides ground to the scan tool.

The data lines monitor the module for diagnostic purposes and for diagnostic trouble codes (DTCs).