Low Speed Wiper Function
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Junior Member
Joined: Nov 2011
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From: St. Paul, MN
2002 Mercedes-Benz E320
Low Speed Wiper Function
I am noticing a minor but very odd and occasionally very annoying incident. There are three speed settings for the windshield wiper but mine only works on setting 2 and 3. I researched this and found there may be a worn down gear in the wiper linkage but the strange thing is when I first start the car in the cold weather I will turn it to speed 1 and it will work fine for 10 minutes then just stop. It's very intermittent. I am quite honestly stumped. 
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
Do the wipers "park" in the correct position when you turn them off? If so, check the wiper switch or the wiper combination relay. The wiper motor function and electrical interface is the same for position 1 (intermittent) and position 2 (low speed), so a problem with the wiper motor/park-run switch would affect both, not just position 1. Does the "washer" switch cause the wipers to cycle?
Thread Starter
Junior Member
Joined: Nov 2011
Posts: 54
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From: St. Paul, MN
2002 Mercedes-Benz E320
They usually do but sometimes it will stop just slightly above where it is supposed to park. The washer switch is also intermittent. Sometimes I use it and it will swipe the windshielf three times and sometimes when I wash the windshield it will not automatically do that and I will have to move it to position two since position one does not work to wipe the fluid off. Usually when I use the washer function and it is supposed to wipe three times or whatever it will do it but sometimes it won't. Every time I use the washer fucntion it will disperse fluid but about 20% of the time will not engage the wipers.
Last edited by bimmerc90; Dec 3, 2011 at 01:06 AM.
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Joined: Jun 2011
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From: Denver, Colorado
1994 Mercedes E420
I'm actually kind of glad I found this thread...my wipers don't work when I actuate the washers. I actually have to physically turn the wipers on to wash my windshield. Sometimes I have the same issue as Bimmerc90. The Windshield wiper motor was replaced in 2009, could this be a funky fuse (mine seem to be all original) or relay related? I'd hate to have to pull the steering column apart to replace the stupid switch....
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Joined: Nov 2002
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
bimmer90 and E420guy -
I think both of your problems are the wiper switch. Take a look at the attached wiper schematic. Note that the wiper switch is a 2 pole, 4 position switch and note that one of those poles (inside the green box) is connected only to the position 0/wash and position 1/intermittent functions. As I have outlined in red, a failure in this part of the switch will affect both the intermittent and wash functions and only those functions.
A bad switch also fits the "sometimes it will stop just slightly above where it is supposed to park" because the circuit is designed to "short" the motor in the park position, thus providing regenerative braking to help halt that big wiper arm. Intermittent mis-parking by just a bit suggests there is no regenerative braking because the wiper switch is bad or "open".
Before you disassemble things, try the old mega-blast-o-WD40 into the switch, then cycle it, to see if you can clean the contacts.
Hope this helps,
- FD
I think both of your problems are the wiper switch. Take a look at the attached wiper schematic. Note that the wiper switch is a 2 pole, 4 position switch and note that one of those poles (inside the green box) is connected only to the position 0/wash and position 1/intermittent functions. As I have outlined in red, a failure in this part of the switch will affect both the intermittent and wash functions and only those functions.
A bad switch also fits the "sometimes it will stop just slightly above where it is supposed to park" because the circuit is designed to "short" the motor in the park position, thus providing regenerative braking to help halt that big wiper arm. Intermittent mis-parking by just a bit suggests there is no regenerative braking because the wiper switch is bad or "open".
Before you disassemble things, try the old mega-blast-o-WD40 into the switch, then cycle it, to see if you can clean the contacts.
Hope this helps,
- FD
Last edited by Floobydust; Dec 6, 2011 at 10:02 PM. Reason: Forgot something . . .
