Wipers Gone Wrong
 

Briefly:

• Screenwash pumps work perfectly
• Wipers, however, are getting more temperamental. The mechanism has been checked for corrosion and it's fine. Sometimes they work first time, other times they don't come on at all on any setting.

Any thoughts? Duff motor? Dodgy connection? Mischevious pixies?

Any difference between just turning on the wipers (in various modes) with the stalk vs triggering them with a wash only.
And have you tried detaching the arms before testing?
That might help narrow it down between stalk, relay, wiring, motor etc.

Sometimes they work with the wash, sometimes they don't.

Sometimes they work sans wash, sometimes they don't.

Garage checked the mechanism and said it's not corroded but gave it a good rinse with lubricant anyway. All the while they had the car the wipers behaved.
5 minutes after i drove off, they stopped working.

They said they've replaced loads on VAG group wiper mechanisms as they are metal part running through an alloy bodyshell (or the other way around) and where the two metals meet that's where they corrode. Either way, they said the problem has been on VW's / Skodas etc for years and still exists on the newer models.

Mine did this on a previous D2. The commutator in the motor was so worn that sometimes the brushes didn't make proper contact and sometimes they did.

Replacement motor from our sponsors sorted it.

That is what I wanted to hear - thank you.

I suspected something along those lines after reading a thread here and there was a photo of a worn motor; I had a hunch the wipers were being affected by movement and a lurch or bump was making a connection somewhere (or stopping a working connection). Plus it's got worse over the last year, indicating something was wearing out.

I know the switch is good; I know the mechanism isn't rusty; it had to be the motor or a connection to it.

I'll get one ordered in the morning.

That would be my guess too.

Not had it on a D2 (yet) but I have had the same fault on other cars. Sometimes it's just worn out brushes I think. When the brushes get so worn that they're close to the end of their travel, the spring tension becomes too weak to make a reliable contact with the commutator.

I can remember on one car I had the fault on (a BX I think), reaching out of the window in the pouring rain to give the wipers a nudge, which was usually enough to get them going again.

Ouch. £300 for a wiper motor from the local Audi dealer.

A8 Parts had 2 in stock at half that but I'd be replacing a 13 year old motor with... an even older motor and that doesn't make sense.

That's my Xmas present from Mrs303 sorted.