Common wiper fault?

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Bear in mind that I'm using the same Haynes diagram as you - which could be wrong, but...

Whichever pin or colour it is, the 12V that's permanently live when the ign is on is the wire that is for the park function. The way it works is this. Some of the other wires start the wipers moving for the once or wash&wipe functions, and are only connected while you hold the stalk switch. The rest of the others feed 12V to the motor while the switch is on, but feed it to different brushes in the motor. The brush opposite the earth brush makes it run fast, and other brushes at various angles make it rum more slowly. Whenever the wheel that drives the wiper moves from the park position the switch turns on the power to the motor and keeps it running until the wheel returns to the park position. For some reason LR make it look more complicated by running the 12V permanent from the wiper switch - most other cars I've looked at this on run it directly from 12V at the fuse box.

If you take the park switch off the motor gearbox and operate it while connected electrically, the wipers should move until you turn it off (with the ign switched on). if they do the switch is not being operated by the wheel. If they don't try shorting across the switch. If the wipers move, the switch is dead.
 
So I guess the most likely fault is a problem with the brushes/motor that run off the perm live bearing in mind i have a new park switch and the other functions run fine?
 
When fitting the gear/crank assembly into the motor did you first fit on the shaft the cupped spring washer?
Without it the gear would be too close to the switch causing the wipers to park at the point you switch them off.
 
Yup spring washer fitted.

I'm kind of assuming now that when the wheel boxes seized the motor perm 12v supply to the brushes cooked them? Had to drive home (200miles) with the perm supply on with seized wheel boxes.
 
Some clarity. With the new switch removed but connected the motor runs with the perm supply, and stops if i depress the switch. So alls working correctly except the switch plunger or the bit the pushes it. i only have to move the switch plunger 1mm or less for it to function, would this assume its too long or contacts inside at fault?

Also checked with the old switch which does bugger all so assume contacts are past it.
 
Very little movement is required to activate the switch 1mm is about it.
It sounds like the position of the cam in relation to the switch is the issue.
The cam too close to the switch would stop the feed so that they park at any point the wipers are switched off at the stork.
 
Agree that does appear to be the issue, what could have changed from pre wheel box failure to now i wonder, there doesn't appear to be any float on the gear spindle and the switch pusher appears fully home on the back gear wheel.
 
Not that i can tell by comparing it to an old wiper motor i have.
Striping down the motor again later to have a better look inside at the back of the gear wheel.
 
Ok so the gear wheel has the spring washer under it. so no float in the spindle position, did get a moment of the correct function then it stopped doing what it should, back to no drive to the park position.
Do get 12v on the return wire when the switch if removed from the motor body which suggests still have an issue with the plunger pusher being too near the plunger tip all the time. The plastic part on the back of gear wheel seems to be in contact properly with the gear wheel itself.

So what else could it be? I'm at a lose now.

Time to bite the bullet and get a new motor or just the gear wheel and a switch?

I hate being beaten by a simple mechanical thing! so bloody annoying!
 
The only thing I can think of trying now is shortening the plunger until I t works properly (do it in small increments).
I know it is not really the done thing but as I see it you will not lose out, other than a switch that will not be interchangeable with another motor.
 
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