A screenwasher jet is the mechanism by which screenwash is squirted onto the vehicle windscreen to aid clear visibility and safe driving. Screenwash is pumped from the screenwash reservoir by means of a stick-lever on the steering column. It’s carried by plastic tubing from the reservoir to two small jets which lie just below the exterior of the windscreen. On the rear windscreen there may be only one jet. These jets can be angled to get the optimum direction onto the windscreen. The use of windscreen wipers during operation of the jets will obtain the best results in thoroughly cleaning the windscreen.
There will usually be a setting on the steering column lever that will cause the windscreen wipers to activate automatically with a spray of screenwash from the jets.
Poor jet spray is likely to be caused by the jet nozzles becoming blocked by debris in which case the screenwash is not able to escape from the jets. If the jets are inoperative the wipers will generally smear the windscreen making visibility poor. If the screenwasher jets are not angled correctly they will not spray the screenwash onto the correct portion of the windscreen. In extreme cold weather the screenwasher jets may freeze up and not allow water to be sprayed onto the windscreen. It’s also possible for the plastic tubes which carry the screenwash to perish and leak which will prevent fluid reaching the jets. Pools of water under or even inside the vehicle may be apparent if this is the case.