the present invention relates to a system for use in motorized vehicles to provide a vehicle back - up alarm system , intended for mounting on a vehicle , that also incorporates an apparatus for detecting and alarming low battery conditions . preferably incorporated into a main housing are the electronic components that perform power regulation , system control , voltage sensing , timing , alarm tone generation , sound emitting and , optionally , light emitting . the housing serves to securely fix and retain these components and to protect them from moisture and dirt . the circuitry is connected to the vehicle upon which it is installed by preferably three connection terminals situated on the housing . distinctive tones and / or lamp sequences alert the operator and those by - standers within proximity to the vehicle to different alarm conditions .