GM Service Manual Online
For 1990-2009 cars only

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).