Video event recorders are coupled to a vehicle power source via an on-board diagnostic system including its power bus, data bus, and scanner port connector. Video event recorders are provided with a power input arranged in conjunction with a standard ODBII type “D” connector. Systems further include an extension cable between the connector and the vehicle event record to accommodate mounting needs associated with each. In advanced versions, both OBD power and data networks are coupled to the vehicle event recorded such that data relating to vehicle diagnostic systems can be captured in a triggered event along with video data. In addition, some versions are provided with special detection mechanism to determine the use state of a vehicle and adjust application of power accordingly. Thus an “in-use” detector is coupled to the vehicle and/or OBD systems to provide feedback which helps to conserve power and regulate the power connections.