Author Topic: want info on repairing 2 speed windscreen wiper switch  (Read 4044 times)

rutger kohler

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want info on repairing 2 speed windscreen wiper switch
« on: July 07, 2013, 11:37:19 »
Hi there, I have repaired the turn switch on my 280sl some time ago with the excellent info from this website.  The  windscreenwipers, however, have only ever gone on one speed which hasn't really worried me, but the other day I found I could get the second speed by selecting the second speed then pushing the 2 speed selector switch slightly towards the outer end of the stalk, and keeping it there. 

Something is obviously worn inside and if I could repair it I probably would someday.  I have looked in the technical manual and electrical posts but can't find anything on opening up the plastic stalk housing with the 2 speed wiper switch inside it.  Has anyone done this successfully, and got it back together again?
1969 280 SL Manual gear shift
1972 280SE 3.5 auto

66andBlue

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Re: want info on repairing 2 speed windscreen wiper switch
« Reply #1 on: July 07, 2013, 18:51:46 »
Hello Rutger,
haven't had the time to add this to the Wiki: http://www.sl113.org/wiki/Electrical/SteeringColumnSwitch
but here is the very short version.
Take a close look at the movable portion on the head - I call it the cap - and you should see the end of a pin. That pin limits the travel of the cap and prevents it from being pushed off the switch by a spring inside. The attached photo shows all the parts under the cap. I used a Dremel with a very fine conical cutter and removed a bit of the plastic until I could pull the pin out. Ber careful not to loose the larger spring inside. There is another spring under the rocker switch riding on a small ball. Sometimes the ball gets dislodged and the rocker switch doesn't function properly. The switch itself is also held in place by a shorter pin (on the right in the photo). The are two pairs of wires (2 green, 2 black) under the contact plates. When the cap is pushed in a solid ridge pushes on one of the contacts when the rocker is in "position I". When it is in "position II" then the cap cannot be pushed in - see the photo in the Wiki for details.
Once you have it apart it will become obvious how this switch works.
After re-assembly I used a 2-component cement (PC-7) to fill the in the area that I had cut out, removed the excess with sand paper, polished the surface with a very fine grid paper and then spray painted the repair spot.
Good luck with the repair!
Alfred
1964 230SL manual 4-speed 568H signal red
1966 230SL automatic 334G light blue (sold)
1968 280SL automatic (now 904G midnight blue)

rutger kohler

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Re: want info on repairing 2 speed windscreen wiper switch
« Reply #2 on: July 07, 2013, 22:01:21 »
Hi Alfred, this is exactly what I wanted, thankyou very much. This definitely belongs in the Technical manual.

thanks again

Rutger
1969 280 SL Manual gear shift
1972 280SE 3.5 auto