Abstract: A brake monitoring and warning system is intended for use on a motor vehicle (110), and more particularly is intended for use on tractor-trailer combinations. The vehicle includes plural, powered brakes. Each brake includes a brake activation arm (18) and a mechanism (16) for shifting the brake activation arm between a brake-off position and a brake-applied position, such as an air-driven cylinder. The monitoring and warning system includes a sensor (26) which is connected to the brake-activation arm (18) and monitors the position of the brake-activation arm. The sensor generates and transmits a brake condition signal which is representative of a safety condition of the brake associated with a particular brake activation arm. A logic mechanism is connected to the sensors and receives and interprets the brake condition signal. Visual (160, 162) and auditory (164) warning devices are connected to the logic mechanisms for warning the vehicle operator of the safety condition of the brakes on the vehicle.