A washer system that sprays weakly or not at all usually has a blocked nozzle or a failed pump, in that order.
Pumps are listed by their fitment and by whether they serve the windscreen or the rear glass; the two are separate pumps on most vehicles. A pump that runs but does not spray usually has a blocked filter screen rather than a dead motor.
Nozzles clog with fluid residue and with wax. They can often be cleared with a pin, but a nozzle that has been cleared repeatedly is usually a sign of fluid that has been mixed or left to sit.
Heated nozzles are listed separately and are fitted to vehicles with a cold-weather package. The heating element fails before the nozzle does.
