Embodiments described herein relate to a motorized door lock detection system. Some embodiments of the device include a sensor gear that meshes directly with the gear system of the motorized door lock. As the sensor gear rotates, it drives the rotating contact of a potentiometer, varying the voltage in a reference circuit that corresponds directly with an angular position of the thumb-drive used to drive the deadbolt. In some embodiments, a conducting member that rotates with the output shaft of the deadbolt contacts a plurality of electrical contacts positioned such that they are contacted when the deadbolt is in a position range that requires more precise position monitoring. When the conducting member is in contact with a deadbolt, power is supplied such the output from the potentiometer can be determined. In this way, power to the potentiometer and/or controller driving the potentiometer can be limited.