A method or system for controlling a vehicle comprises entering a programming mode or a guidance mode based on user input to a switch. The user can enter a guidance program in accordance with a predetermined sequence of inputs of the switch by the user, where readiness for each successive input is indicated by a light source. A guidance mode is managed for controlling an implement height in accordance with the entered guidance program. A height sensor can sense an observed height or elevation of an implement of the vehicle (e.g., relative to the absolute target height of the implement above the ground). The observed height is controlled in accordance with the guidance program (e.g., the target height) if the system or the data processor is operating in a guidance mode.