This potentiometer converts the mechanical position of the header into an electrical signal for the combine’s control system. It is mounted on the header assembly and provides feedback that governs header height and tilt response. A failing potentiometer produces erratic header movement or a loss of height control, as the control unit no longer receives a consistent position signal. The manufacturer machines the internal resistive track and wiper to match the original assembly’s output curve, so the control unit interprets the voltage range correctly without recalibration.