Scan Tool Does Not Power Up

Diagnostic Chart:

The data link connector (DLC) provides operating power for the scan tool at circuit 2140 (battery positive voltage) and at circuit 550 (ground). The DLC provides the Class II serial data signal at circuit 1807 and signal ground at circuit 151. The DLC provides the keyword signal at circuit 2960 (for ECM and TCM) and circuit 5043 (for the EBTCM). The scan tool will power up with the ignition Off.