A brake controller has a control dial with a series of full color LEDs arranged around the dial. The dial with its LEDs is in a module mounted on the dash of the towing vehicle and connected by a cable to a main module mounted out of sight. The dial is a rotary encoder pushbutton mounted on the same circuit board as the LED chips. Status information is output using the LEDs primarily based on color. Substantially all setting input is provided solely by user manipulation of the dial, pushing the dial in to change setting input mode, with the value of the input reflected in the number of LEDs being lit in a color corresponding to the brake controller setting being changed, as the user rotates the dial either clockwise or counterclockwise to change setting values.