E30 Zone

When I press the switch the motor makes some noise but no water comes out. Doesn't seem to be a blockage at the wiper end so either the motors not actually working or there is a blockage somewhere further down the pipe.

Any advice as to whats the best way to fault-find this sort of problem is?

Pipe breaks where it enters the tailgate hinge. It's probably flooding the top of the headlining!

Check where the tailgate hing covers are underneathe them.

I stripped the internal plastic inside the tailgate and can see the flow of water in the pipe moving along as far as a little white connector thing. so it appears to be either in this connector or into the main wiper motor part that it's blocked.

The white thing you mention is a check valve i think, is it fitted the right way round?

Water will only squirt out of the nozzle when the wiper arm is moving, as there is some sort of switch controlled by the movement of the arm (difficult to explain.) So if you haven't got the wiper working, the washer won't work either (although you should hear the pump buzzing.)

The wiper is moving fine, just the screen wash.

The check valve seems to be correct, or at least its all properly connected up. What does it check? Would it stop the water if it was inoperable? Does the wiper motor do anything or is that just a straight through pipe?

Grrrmachine wrote:Water will only squirt out of the nozzle when the wiper arm is moving, as there is some sort of switch controlled by the movement of the arm (difficult to explain.) So if you haven't got the wiper working, the washer won't work either (although you should hear the pump buzzing.)

If the wiper motor is in the rest position, the washer motor can work. It's when it's moving back to the rest position that the washers stop.

Something I just noticed was that the water I can see moving in the pipe seems to have a lot of air pockets, not a constant stream. Is it possible the motor at the reservoir end isn't creating a strong enough flow?

Would it be the same motor used for the front reservoir? I'm sure I have a spare somewhere...

h7fal wrote:The wiper is moving fine, just the screen wash.

The check valve seems to be correct, or at least its all properly connected up. What does it check? Would it stop the water if it was inoperable? Does the wiper motor do anything or is that just a straight through pipe?

By check i mean non return, they are fitted so that it maintains water in the tube ready for the next operation as opposed to letting all the water from the nozzle draining back to the tank.
I had a similar problem recently and it turned out to be a kink in the pipe in the hinge area behing the tailgate trim.
You could try to just wire the pump directly to a 12v power source such as a battery charger or a battery itself. These little pumps are pretty powerful, when i tested mine off the car it squirted a jet of water for about 5 meters or so.

The kink in the pipe makes sense - I'll trace it right round the tailgate. The water is definitely not being maintained for the next spray, you can see it slide back away from the check valve.