Abstract: A warning device for a coupling system including a non-mechanical switching device for determining whether a latching mechanism in the coupling system is locked and a signalling device. The switching device providing a first output the latching mechanism is locked and a second output when the latching mechanism is unlocked. The signalling device providing one of a plurality of unique signals to an operator based on the outputs provided by the switching device, wherein each of the plurality of unique signals indicates a unique coupling condition of the coupling system.