OBD1 to OBD2 Convertor Connector Lead Cable Adapter Diagnostic Scan Tool For GM GM 12 pins to OBD2 16 pins Diagnostic Adapter Lead Cable One end for the 12 pins OBD port on a GM car. The other end for the 16 pins OBD2 diagnostic tool. OBD1 to OBD2 Convertor Connector Lead Cable Adapter Diagnostic Scan Tool For GM