The PLC universal automatic car alarm system is an electronic device installed in vehicles in an attempt to discourage theft of the vehicle itself and its contents or both. PLC universal alarm system typically consists of sensors, a control unit, and an alarm system, which can include a siren, flashing lights, and in some cases, a remote notification to the owner. These systems are designed to deter theft and provide a warning if someone tries to break into the vehicle. Car alarms work by emitting high-volume sound constantly creating attention or awareness to any form of unauthorized approach to the car is detected. Such alarms may also cause the vehicle's headlights to flash and notify the car's owner of the incident via a paging system and also interrupt one or more electrical circuits necessary for the car to start.