Body Control Module is an electronic control unit that monitors and manages different electronic accessories within a vehicle’s body. The BCM’s primary function is load driver control, and it interacts with other on-board computers through the vehicle bus of the vehicle. The BCM normally regulates the air conditioning, central locking, power windows, power mirrors, and other features in an automobile. Triggering relays that then carry out functions within the car, including turning on the turn signals, locking the doors, or turning down the interior lights.