Abstract: A pane washing appartus for a motor vehicle comprises a pressure source to drive a cleaning fluid which in turn activates a valve and a jet nozzle associated with a jet-nozzle carrier which is movable from a pulled-back rest position to an operational, deployed position. The valve is first opened once the jet-nozzle carrier has moved the jet nozzle to the deployed position. The valve includes a cap which loosely covers a passage opening in the jet-nozzle carrier leading to the jet nozzle but which follows movement of the jet-nozzle carrier until its peripheral area contacts a fixed stop thereby uncovering the passage opening immediately before the jet nozzle reaches its deployed position. The cap is pressed against the jet-nozzle carrier by cleaning fluid pressure, a spring or a permanent magnet.