Some of the electrical components in the vehicle viz., the interfacing of the fuel injection system,
Horns, starter motor, and fog lamps all use relays to pass electrical signals to the next device. A relay functions in that a low current circuit known as the control circuit opens and closes a higher current one known as the power circuit. If a relay is able to induce or cause a malfunction in the related component then it must be faulty. In general, relays are installed in the hood compartment and in interior fuses and relays' containers.