It is likely that it's a simple fix as I found out on my 1999 Scenic. Under the bonnet is a cloth sound deadening panel, carefully get access under it. You should find a pipe coupling leading to a T junction, I found that the pipe was just a bit tired and worn, hence when the bonnet was closed it gave under its own weight and kinked blocking the line. Decouple from line, cut off as little as possible but make sure enough to get to good pipe and then refit. Hopefully this will fix problem, if it doesn't it might be the jets themselves but the chances of all 4 failing simultaneously are beyond remote. Alternatively could be something wrong with washer bottle/piping further down if so:-
1. You will need to jack up your car and remove the roadwheel, it's a good idea to put it on axle stands, if you haven't got any take some precautions in case of jack failure e.g. lie spare wheel under drivers door area.
2. Free up the wheel arch liner, it'll be in 2 pieces, 1 behind the wheel and one in front. Go for the rear one first, look for some screws and there will almost certainly be some big plastic lugs that just get carefully pulled out (only remove enough fittings to enable access into the void without too much agro). For the most part the liner is just tucked behind the outer edge of the wing so just needs careful persuasion. Swing the liner out of the way as best you can (tuck it behind brake discs?)
***NOTE: At this point I found a lot of compacted sandy silt which was very easily removed. I noticed that the sunroof drain pipe fed into this area and that at the end of the pipe was a flap fitting. With all the silt the flap could not open properly which inevitably will cause poor drainage from the sunroof leading water to back up the pipe and find its way into the cars interior. If you see similar I suggest taking a look at the other side and clearing accordingly.
3. Find a clean rag and cover discs, then get a couple of carrier bags or similar to also cover discs/brakes so they don't get washer fluid on them.
4. Look under wing and see what else you need to remove, I had to free up part of the front liner as well.
5. There was just one nut up under the wing for me, however getting the plastic mounting of the tank off it was a bit awkward. The metal bracket was flimsy and just bent when pulled on so get a small flat blade screwdriver between bracket and plastic and work it off far enough to get fingers in behind and pull carefully pushing against the bracket so it doesn't bend.
6. As the tank is lowered water will spill if it is quite full, (the filler neck slides through a hole in the tank, so leaves a hole as tank is lowered)
7. Unclip wiring from tank as necessary.
8. Carefully remove pipes (way need small screwdriver to get started (be careful of puncturing/splitting pipes)
9. Decouple electrics plug (usually has a retaining lug that needs to be "activated")
10. If you need to remove washer pump get a reasonably large screwdriver under the pump and carefully prise upwards (it's just a solid pipe passing through a rubber seal with a tight fit, when refitting put some wash liquid on to help)
All the best
TheDivvy
September 2008