W202 Wiper stopping in middle of screen

[GP801]

Had very similar on our 124. The wiper worked in a totally random fashion. Replaced the relay and all fine. 35 Euros so hardly worth trying to repair it.

 

[Dec]

by the way sometimes it works well

Then that strengthens the case for a broken joint, I bet every time you hit a bump it works again.

Dec

 

[Dec]

Had very similar on our 124. The wiper worked in a totally random fashion. Replaced the relay and all fine. 35 Euros so hardly worth trying to repair it.

True, but if you owned your own soldering iron then you could fix it a lot faster than you could replace it.


Dec

 

[GP801]

True, but if you owned your own soldering iron then you could fix it a lot faster than you could replace it.


Dec

You have clearly never seen me try to use a soldering iron

 

[canery]

Had very similar on our 124. The wiper worked in a totally random fashion. Replaced the relay and all fine. 35 Euros so hardly worth trying to repair it.

what you wrote encouraged me more
35 euros is so much for me --> (it is worth 2 or 3 day working to earn it)

Thanks everyone for your comments.
You are so supportive.

 

[canery]

thans guys! When I disassembled it, i saw at least 5 broken joints.
I soldered them and it worked like charm!
you saved me from a lot of troubles.

this is the pic
before and after (I know the solders a bit chubby but PCB ways(?) were about to break that is why they are so big

full size photo

http://imageshack.us/a/img694/4232/09y7.jpg
http://imageshack.us/a/img826/97/fs9o.jpg

 

[Dec]

Well done and thanks for the feed back, nice to be able to do it yourself.
The plug pins seem very dirty or is that just the camera?

Dec

 

[canery]

Well done and thanks for the feed back, nice to be able to do it yourself.
The plug pins seem very dirty or is that just the camera?

Dec

They are dirty
But I did not have any kind of cleaner spray so I used my fingers to clean the pins

 

[NDFR]

Nice job canery

 

[DSB SL AMG]

great thread....the wiper mech / clutch from MB are circa £1000....you can get breakers spare for £150.

 

[Ted]

Spam reported

 

[absent1980]

Hi all

I have an intermittent problem with a front wiper on w202. It used to suddenly change mode or even start working while switched off. I took it to a garage. They checked alignment, motor and replaced N10 rilley (with second hand one) and all was ok for 2 days. Now it occasionally stops at random places or switches wiping modes itself. I have to switch it off and on again to fix the problem.

Any ideas? May be combination stalk?

Many thanks in advance.

 

[Dec]

What year is the car?

Dec

 

[Lancasp1]

Wiper problems

I collected a 124 today and it developed this problem - slowing down then stopping at various points before stopping altogether.
A feature that I haven't seen mentioned is the wiper starting when you use the indicator even if the wipers aren't switched on accompanied by a hot smell.
I changes the fuses but no improvement.
I called SPR who said that this sounds like the indicator stalk which sounds like an easier fix than gears/motors etc.
They are looking at it in a couple of days so I will post the result.

 

[ajcb]

W202 wiper arm doesn't move. Motor runs when switched off at stalk.

w202 wiper arm doesn't move with motor and motor runs all the time ignition is on even if wiper switched off at stalk switch

History:
The car is a 2000 C200. TheWiper has been working perfectly at all speeds with no slowing, altering of park position etc. since motor and gearing had been replaced with new parts about 4 years ago.

Problem:
Today whilst driving I switched the wiper on at the stalk switch because it had started to rain. The wiper arm worked perfectly for about 2 or 3 minutes and then suddenly stopped at a 90 degree angle in centre of screen. I turned the switch on the stalk off and then on again and as the wiper arm still did not move I turned off the wiper motor, stopped the car and turned the ignition off. I then started to turn the key to start the car to find that as soon as the key reached position one I could hear the wiper motor running even though it was switched off at the stalk.

I drove about 200 yards home and turned the engine off. I then turned the ignition on and could hear a very loud wiper motor. The arm did not move but the motor sounded faster when I put it in the fast position 3 on the stalk. I could hear it remaining running in all 4 positions (ie off,1,2, and 3).

Action so far: relay changed, plastic cover taken off gearing by wiper arm - movement nicely greased and moves freely by hand. Put stalk switch in off position and turned ignition key to position 1. Heared a couple of clicks from relay as motor started. Wiper arm did not move. Same happens when switch in ON position. Can move wiper arm across windscreen freely by hand.

Questions:

I am puzzled because the wiper motor runs when switched off at the switch on the stalk as well as the wiper arm not moving when the wiper motor running.

Is this (a) 2 problems coincidentally starting at the same time or one problem causing the other very soon after it happened? or (b) Is it possible there is a fault in the wiper motor preventing the motor turning the gearing and at the same time making the motor try to draw power so that when the ignition is on the motor closes the relay and comes on even if the switch on the stalk is turned off? or (c) If the stalk switch is faulty so the motor runs all the time could the fault in the switch somehow cause the wiper motor to run but the wiper arm not to move.

Anyone experienced this double problem or got any ideas?

 

[ajcb]

Whoops..should not have written "Can move wiper arm across windscreen freely by hand". Should have written "Can move wiper arm freely from centre position across passenger side of screen by hand and back to centre point by hand but cannot move it across drivers side of screen freely by hand."

 

[ajcb]

Progress

I had forgotten that parking the wiper (or one might more correctly say parking the motor) happens when the switch on the stalk is turned off after using the wipers. That explains why the motor is running in off. It is trying to park but cannot as either it is no longer connected to the the wiper arm or the wiper arm is jammed.

It’s good news to be just looking for why the wiper arm suddenly stopped. If the motor is ok either nut 2 holding the motor spline in place is loose or the nut 1 holding the wiper rod is loose or the wiper rod itself is sticking and needs greasing. Hopefully the plastic gear in the motor has not been damaged when it happened.

Given the facts so far any thoughts on which of these scenarios is the cause given the wiper arm suddenly stopped at 90 degrees in the centre of the screen whilst switched on and working and that the wiper arm moves freely by hand from where it stopped in the centre of the windscreen across the passenger side of the windscreen and back to the centre but will not move freely by hand from the centre across the drivers side of the windscreen to the park position?

 

[Dec]

I’m finding it hard to follow but from what you have described so far it would seem the stalk switch is damaged or burned or melted, this is short circuiting the wiper switch causing the motor to run all the time the ignition is on.

You probably have a nut loose on the reae of the mechanism, or, and unlikely , striped gears inside the wiper motor gear box.

First open the stalk switch, have a good light and a mirror to see the underside and back, see below link.
How to inspect the stalk switch, see… Wiper has started working on it's own - Mercedes-Benz Owners' Forums
Trying to clean it with switch cleaner, as suggested in the above link doesn’t usually work.

The stalk switch in the top picture is undamaged and the bottom picture shows where it has melted.

Can you confirm that the wiper motor runs all the time that the ignition is on even with the stalk OFF?
The wiper arm/blade can be moved by hand on some parts of the windscreen?

Dec

Edit; you are going to have to fix the stalk first, before you fix the wiper motor parking problem.

 

[Dec]

Just realised that your car is 2000 so the switch is different and may not in fact be damaged as it’s a different design to the older one in my previous post, note your stalk end button doesn’t come off, it is the rest of the stalk, with the writing on it, that is puled towards the steering wheel, mark all 3sections with tape to help reassembly.

See Post #4 & 6… intermittent rain sensor - Mercedes-Benz Owners' Forums

There are 2 Yellow relays in the back of the fuse box, remove 6 screws to access, the deal with the intermittent and delay wiper action, try removing one first then the other to see if that will stop the constant running problem.

Dec

 

[ajcb]

Thanks for your help Dec

I can confirm that the wiper motor runs all the time that the ignition is on even with the stalk OFF

and that the wiper arm/blade can be moved by hand on some parts of the windscreen?

Please note that the motor is correctly running at different speeds according to which position 1-3 the switch on the stalk is set. It also runs in position 0 (the off position) but I am now fairly certain that this is because when the problem occurred the wiper did not stop in the park position and the motor is still running because it knows the wiper arm is not in the park position and is trying to move the wiper to the park position. Does this make sense. Do you think it is plausible?

I believe that when in position 0 (0ff) the stalk switch sends current to the park terminal in the motor to make sure the wiper arm moves to the park position.

I believe one of the 2 nuts became loose or something else broke on the gearing preventing the motor connecting with the wiper arm which stopped the arm moving or parking.