Abstract: An electronic brake control for trailers utilizing solenoid operated electric brakes wherein trailer braking is controlled by sensing the rate of deceleration of the towing and towed vehicle producing an electric signal controlling a voltage controlled oscillator having a fixed frequency output and a variable pulse width, the pulse width increasing proportional to the rate of deceleration. The pulse signals are amplified and energize the towed vehicle electric brakes in an oscillating or pulsed manner to minimize skidding and brake locking. A light sensing circuit selectively shielded by a pendulum produces the automatic deceleration responsive signal, and manual apparatus are employed to produce trailer braking without braking of the towing vehicle. Additionally, the automatic electric brake system control through the brake light circuit is by-passed and isolated by actuation of the emergency warning brake light system.