Wipers wont turn off!

[megadethmaniac]

Went to wash the salt off the front screen of the daily, wipers came on and now wont go off! They`ll go faster but won`t quit.

Where to start? Wiper stalk?

What would you guess

[JPB]

Self parking switch sticking closed.

[that bloke]

I'd agree, probably the self park switch. If you can get the motor apart, you'll probably find the mechanisms jammed up with old grease (and about a pint of water in the case of the last one I took apart ), take it all apart, clean and regrease and it should probably work.

[Luxobarge]

Yep - that, or the relay stuck on.

[Raymk]

Yes, the self-park switch is usually part of the wiper motor. On more modern cars, god knows : They have probably found a way to use a few black boxes, a handful of sensors and a magnificant wiring harness that meanders towards a diagnostic socket. All you will need then, is a friendly electronics technician, a diagnostic computer driver and a wallet full of notes. You could just scrap it like many do. Cynical? Me? What makes you think that? I hope it is easily and cheaply fixable.

[Wicksy]

You don't say what car but as you have experienced the problem after dousing the windscreen area it is a good idea to look at the electrics that could be affected by that action i.e.wiper motor, associated wiring, connectors and relays. The stalk feeds can be checked with a meter but I guess that would come lower on the list of things to check.
Many Brit makers used standard relays in the 70's and subbing them can sometimes be a "quick fix" One of my classics, for example has identical relays for starter and rear screen and guess where they are situated. Only in the plenum chamber just below the windscreen thats all:!:
Some makers also put the wiper motor there with only a sort of plastic sock to protect it, water gets in and plays havoc - as you would expect

[Luxobarge]

At least your wipers are working after a fashion - even though you can't switch them off. Unlike the Polish driver of a Hyundai I saw last night, driving in thick mucky salty spray and rain, who had no working wipers at all. Every time he stopped at lights he got out and gave them a helping hand, which temporarily cleared the screen, but they wouldn't work on their own. In those kind of conditions he must have been driving virtually blind - he was driving like a loony too, overtaking on the inside and generally carving people up. I hope he got pulled.

You can see why wipers are very much an MoT item, with idiots like him on the road. (not that he'd be subject to a UK MoT but you know what I mean....)

Let us know how you get on with your problem.

Cheers

[SlipDiff]

modern wiper motors generally have a 'park' section on the motor commutator (or somewhere similar). for constant wiping, this 'park' section is given a live feed, therefore when the motor has completed a full revolution, it can not park as the circuit is still live; the wipers will operate continuously, even if wiper stalk is switched off.

for the wipers to 'park', the live feed to this part of the motor has to be switched off. a role which is now being fulfilled by the ECU but, as others have said, sometimes relays.

check feeds to the wiper motor: you should have an earth, a number of lives of different voltages (for different wiper speeds), and an earth that will briefly switch to a live when the intermittant wipe/ one touch wipe is requested. the live should switch off before the wiper motor completes one revolution, then the wipers will park again. if it stays live, then wipers will continuously operate.

you didn't say what car you have (it mustn't be french, cos they never go wrong) but i hope this might help a bit. I'm no auto electrician; but i have a bit of an idea how these modern things work. as i say, hope it helps.

[megadethmaniac]

Thanks to all that commented.

My initial guess was the stalk (switch) and it proved to be correct. The garage, a local Mot Station that are the kind that try to pass your car rather than fail it, that looked at it for me, guessed that that was the case (well I can get them to stop if i hold the switch in exactly the right spot..) but checked it out before ordering the part as the switch was in their view a bit expensive... £90 The guy there expected £20-40 but not being the case wanted to be 100% sure which was good. How many of us have been led up the Garden Path by the..... Well we think its this, then that, then the other and fobbed off with the answer, well each played their part in fixing it! (and clearing your bank balance!!!!)

They couldn`t confirm that it was the switch by selecting varied wires on the loom side of the switch and therefore ended up discussing the matter with the local marque dealer in Basildon who were apparently very helpful. They suggested running a live wire to varied points on the wiper motor and checking that way. You don't commute from Hertford to Basildon do you Slipdiff?

The Car is an 04 Hyundai Matrix, quite the least reliable car I`ve ever owned... and I`ve owned Fiats!!!!!!! Fiat = Fix it again Tom or fix it again tomorrow. I know the Jokes.

Anyway it appears that did the trick. One new switch was the order of the day, that and a new pump for the washers as apparently in the switch giving up the will to live it fried the pump.

Sorted and without a laptop in sight!