Automotive Relays, Relay Control Modules
Relays are used in many ways for many different components of an engine and the engine itself. At the basic level, relays transmit something from one place to another. Most relays operate through electricity or magnetism. It may be a switch that is electromagnetically operated and connects or disconnects a flow of current that then operates a mechanical device. Relays often take a current and allow it to be amplified to a greater current in another line to accomplish a mechanism. This saves the switch from having to handle the heavy loads of current heavy applications, such as headlights or a horn. The relay may also function as the device between a signal and an action like opening or shutting a valve or throwing a switch. In these cases, the relay is connected to a solenoid or motor that it uses to translate energy into action. All relays transmit messages and accomplish actions whether they are mechanical or otherwise.