What controls the automotive horn

The automotive horn is typically controlled by a horn button or switch located on the steering wheel or dashboard of the vehicle. When the horn button or switch is pressed, it sends a low current signal to the horn relay, which is responsible for allowing a higher current to flow through the horn assembly.

The horn relay acts as an electrical switch, closing the circuit and allowing the higher current to flow through the horn assembly, which in turn energizes the electromagnet and produces the loud warning sound. The horn relay also helps protect the electrical system of the vehicle by preventing the high current needed for the horn from flowing through the horn button or switch, which could cause damage to the switch or the electrical system.

In some cases, the horn may be controlled by an electronic control module (ECM) or a body control module (BCM) in modern vehicles. These modules may be responsible for controlling various functions in the vehicle, including the horn, and can be programmed to activate the horn under specific conditions, such as when the vehicle's alarm is triggered.

Overall, the horn is typically controlled by a simple electrical circuit that includes a horn button or switch, a horn relay, and the horn assembly, which work together to produce the loud warning sound when needed.