An automotive relay is an electromechanical switch that uses a low voltage signal to control a high voltage circuit. It typically consists of a coil, contacts, and an armature. When an electric current passes through the coil, it generates a magnetic field that pulls the armature, closing the contacts and allowing current to flow through the circuit. This action enables the relay to control large electrical devices like motors, lights, and other high-powered components without needing a large, cumbersome switch.

    Relays are used extensively in automotive applications because they are compact, reliable, and can handle high currents with low control power. This makes them particularly useful in a vehicle, where many systems need to be activated remotely or automatically without overloading the car's control circuits.