How Does A Relay Switch Work In A Car

Record the measured voltage and if it is not the right amount then your relay switch is working poorly.

How does a relay switch work in a car. If the component still does not work it is faulty. If one of your accessories doesn t come on and you suspect the relay is bad you can perform a few simple tests. Whenever you operate a switch to an accessory in your car that carries a lot of current such as the lights wipers or horn you run a small amount of current through a relay which in turn closes contacts to operate the accessory. Relays in general are used to enable a low amperage circuit to switch on or off a higher amperage circuit like turning on your headlights.

A changeover relay is built with two circuits instead of one and five pins rather than four. Automotive relays of all shapes and sizes can be found in just about every car truck and even boats. When power flows through the first circuit 1 it activates the electromagnet brown generating a magnetic field blue that attracts a contact red and activates the second circuit 2. Remove your car s dashboard as this is the main site of the relay switches and then turn your car on.

Here are two simple animations illustrating how relays use one circuit to switch on a second circuit. Typically the relay is switched manually using push or toggle switch an everyday example of this is the car ignition switch used to start the engine. If a component that is fed with electricity through a relay see how car electrical systems work terminal of the battery to the feed terminal on the component thereby bypassing the relay and supply wiring. Firstly using a relay means the switching circuit does not require a high current rated switch or cable which reduces cost and weight.

Secondly relays can be positioned anywhere in the vehicle to provide efficient power transfer to the electrical accessory you are controlling.