This gearbox position sensor reports the rotational state of the transmission output shaft to the electronic control unit. It is threaded into the gearbox housing and uses a two-pin connection to send a signal that the ECU interprets for functions such as PTO engagement and speed-dependent hydraulic response. A failing sensor produces erratic or missing speed readings, which can cause the transmission to behave unpredictably or enter a safe mode. As an original AGCO part, the sensor body and thread geometry match the housing bore exactly, so no adapter or thread sealant is required beyond the standard O-ring.