fast wipe problems...

[chrism]

Hi All. Anybody got ideas?

Washer, intermittent wipe and slow wipe all work ok and return, but fast wipe doesn't even start

My thoughts are wiper switch, wiper relay or bad earth - but I haven't a clue where to look first. Anyone had similar symptoms, please? (A few months ago I remember a singular 'hesitation' and I reckon they're connected.)

ps I should have thought to look at the voltmeter when the fast wipe didn't work to see if it was an ailing motor, but everything works on the other speeds...

[Tuga2112]

i would start by taking the relay out (under the steering wheel relay box) and make sure the contacts are not rusty.

i have the same problem. but its intermitent.
the realy in there is both the relay and the control unit with the delay if i remember correctly

[chrism]

Thanks Tuga. The in-car voltmeter dips very slightly when stationary and ign ON when the intermittent and slow wipe are switched, but absolutely no dip when switched to fast wipe.

It's probabably easier to look at the switch first? In either case the lower shroud will have to come off...

Edit:- well, I've established that the switch is okay using a multimeter and I've found (by touch) the relevant relays (I think) close to the UK driver right knee, but being in a single garage with the inability to open the door more than 1/4 out I've found an unimaginable lack of comfort (so 'pain stopped play' ) - MInd you I wouldn't know how to test the relay - other than by substitution (at £70 a pop? )

[Fredjohn]

Chris. The relay can be cheap.
Get one from a Golf Mk 3 (new or from a scrappie!)

This will give you a variable intermittent wipe. It was one of the first mods I did when I got my car.

I'm sure there's a thread or post or something on here that gives the info.

Found it. viewtopic.php?t=8716&postdays=0&postorder=asc&start=97

[chrism]

Update:- Yay

I found the relay by touch and pulled it around a bit to see if it would easily come out.

Of course it didn't - so I transferred my attention to the plastic shroud under the steering wheel that I'd removed to get the switch out. I couldn't fix that either, so I despairingly tried the wiper switch and all the speeds worked .

Tuga's rusty relay must have been right and it needed 'scragging' - but I'm hoping that this 'fix' stays permanent; I shan't tempt fate...

Now - does anyone know where I can replace this plastic part? I think it's too far gone to glue a washer or some other kind of spacer to it:-

[peteoddcar]

Hi Chaps
Sorry to contradict, but the fast speed wiper not functioning will not be as a result of a poor relay connection. The supply to the 3rd brush ( high speed ) is feed direct from the switch to the motor ( orange wire ). If you took the relay out the high speed would still work - it wouldn’t park or delay though.
Cause would have been most likely a poor switch contact, poor connection on switch or motor or a sticky brush.
My money is one the switch contact. Give a spray with Electrical Switch Cleaner give the switch a good wiggle (not and never WD40 on electrics). Allow the switch cleaner time to properly evaporate before testing or you may just need the fire extinguisher ( yep been there done that )

[chrism]

Aw...noo...I thought I'd 'sussed' it...(and I've never had much success with electrical stuff ...)

[peteoddcar]

Chris mate
Don’t be so hard on yourself you probably have sussed it !it’s the switch! It’s like the reluctant hazard switches 9 times out of ten a good workout will get them going again - the switches have a contact lubricant when assembled new, but after 35 years it drys out, this allows verdigris to form thus creating a very high resistance across the contacts.
What’s the other bit you want to fix back on?
I can’t recognise it from 5he photo.

[chrism]

The other bit's the bottom half of the black, plastic shroud below the s/wheel that you have to remove to get the switch out - but I managed to bodge it by sticking a strip of hard plastic over it and making new holes that the fixing screws wouldn't pull through...

The switch was fine - I managed to test the different speeds with my m/meter (smug...) - which is why I 'scragged' the relay with a view of finding if it would pull out easily to replace (since it's effectively hidden from view unless you have the mobility and spine of a serpent ) - but from what you say the very act of disturbing it must've jogged it back into operation.

And I felt sooo... smug that I'd actually fixed something electrical . - That's all gone in a jiffy

[peteoddcar]

Chris
I guess you disturbed something if you are sure the switch was banging the power out, although DVMs can and do lie - or mislead it’s perfectly possible to read system voltage when no current is flowing as soon as the load applies it drops to zero, why I always test these circuits with a real load, for a wiper circuit I’d use a 21w bulb at the motor connector, crude but effective, the 3rd brush in the motor is therefore the most likely they won’t wear much so probably just a bit of “stickshun” with the brush in its carrier.
The ohms setting is more reliable but DVMs do rely on a very very low current passing the contacts.
See ya soon I hope - I’ll message perhaps meet fir a cuppa somewhere

[chrism]

Hi peteoddcar, I took out the switch and tested these terminals for continuity...(ie terminal 53 ->53E in the OFF switch posn, 53A->53 in the SLOW switch posn etc...)



...using the most sensitive ohms setting and they all 'passed'. The terminals were labelled on the switch plastic, so easy-peasy.



Yep agree that my wipers are hardly used and fast setting probably never, so far, so this is likely to be the sticky offender. I guess it was a lucky 'suss'

You're always welcome to share a cuppa