A glass break sensor system is provided for a vehicle having an on-board diagnostic (“OBD”) data link cable and an OBD port. The system includes a modular unit having a microprocessor, a glass break sensor, and a pass-through OBD connector including an input connector configured to mate with the vehicle OB) data link cable and an output connector configured to mate with an input to the vehicle OBD port. The input connector includes a power input configured to be coupled to a vehicle battery voltage input of the 0131 data link cable and to provide power to the glass break sensor device.