As electrical and electronic systems are increasingly used in the automobile, the number of relays involved in the circuits of new models is steadily growing. Many relays are located on the relay board and fuse board under the dashboard or in the engine bay. However, many relays are located inside the vehicle in close proximity to the controlled component. When checking an electrical circuit, a faulty relay is often suspected as the cause of a breakdown until another cause is found. Sometimes a hard blow with a screwdriver handle on the relay releases the jammed parts and the system starts working. It doesn't happen often, but if you succeed, you'll probably brag about it for weeks.