Complete Windshield Wiper Diagnostics and Repair Instructions

[justjakinit2003]

I just barely went through this issue with my 1999 C280. I would like to take a second to completely explain my experience from beginning (problem) to end (solution). Initially, my wiper was occasionally sticking. At the time I was thinking that maybe the type of wiper that I bought from auto zone wasn't compatible or that maybe the windshield glass treatment that I was using was causing the rubber of the wiper not to slide as it normally would. Eventually the problem got worse and would completely stall. My wiper motor would continue to make noise as it attempted to force the wiper down and would eventually shut itself off. I would later have to get out of my car and reengage my wiper switch to the on and then off mode as I guided the blade back to its starting point so that it was no longer frozen in the middle of my windshield. At this point I decided that it was time to take a deeper look at what was going on with my wiper system. After reading about a million different forum posts I was able to find and create a very good path of diagnosing and fixing the problem. ***I will reference the following two links throughout. Don't worry about viewing yet. Just follow my path. link A- http://202tech.mkosonen.com/howto/wiper.html link B- http://members.lycos.nl/mbenz/windshield_wiper.htm (link B actually explains another procedure but it has great pictures and directions of removing the MB wiper system as well as how to put it all back together so that it works) First, I just want to familiarize everyone with the main parts that make up the MB wiper system. There are five main parts to the MB single wiper system. 1) First we start with the wiper arm, commonly called the windshield wiper, that everyone is familiar with. 2) Second, we move down to the mechanism that holds the wiper arm, which is technically called the Windshield Wiper Transmission but referred to as the wiper mechanism throughout the links. Strangely however, link B refers to the entire wiper system as the wiper mechanism and then later calls just the transmission the wiper system.....so keep in mind when reading (Viewable at the bottom center of your windshield and about the size of a small football.) 3) Next, we move down to the wiper linkage, which is referred to as the offset plate in link B. The wiper linkage or "offset plate" simply connects the wiper motor (#4 below) to the wiper transmission (take note, you cannot yet see this item without removal of the entire wiper system). 4) Then, we have the wiper motor, as mentioned above. The wiper motor drives the wiper linkage or "offset plate", which activates the wiper transmission, which moves the winshield wiper back and forth in order to remove snow or rain 5) Finally, we have the mounting bracket that holds the above parts 2, 3, and 4 all together and to your car. Start here 1. It is very possible that the solution to your problem is just a quick five minute lube job of the wiper transmission. Take a look at link A for great directions and pictures of how to do this. If this is your problem then you are done. If not....as was my case continue ahead 2. Your next problem could also have a fairly quick solution. Part # 3 above, the wiper linkage or "offset plate" connects to the wiper transmission and wiper motor by a pressed fit, secured by a nut. It is a very common occurrence that the nuts that hold the wiper linkage to the wiper motor and transmission eventually loosen and cause the linkage to slip out of correct positioning. If this happens it will cause your wiper blade to hesitate or stall because the linkage or "offset plate" has to be connected to the motor and transmission very tightly and in a marginally specific timing or position in reference to the motor and to the transmission. Take a look at link B to get an idea of how to remove the wiper system and reset the positioning of the linkage or "offset plate" in reference to the wiper transmission or "wiper mechanism" and wiper motor. But first before you do so you are going to want to pull the wiper transmission off of the wiper mounting bracket and inspect and lube the graphite gear found on the opposite side of what you lubed up in step #1. It is rare for this gear to be chewed up but if it is then you will be replacing the wiper transmission, which I have heard can cost around $ 700.00 for the OEM part and still possibly the linkage and motor ***Back to reseting and retighting the linkage "offset plate". remember that the surface of the linkage is a beveled pressed fit, so as long as the surfaces of the linkage aren't too chewed up you should be able to drive that nut on hard enough to achieve the necessary pressed fit. However, if the linkage is too chewed up from slipping for too long, you may have to buy a new linkage. The best deal that I found on this part was at http://https://www.autopartsway.com/secure/cart.cfm I think it was appx. $ 45.00 or $ 50.00 If you solved your problem here then great!! Many actually do. However, this was not the case for me. I waited too long to take these steps and eventually burned up the gears in my wiper motor. With what I know now this is how my problem slowly progressed. Initially my linkage slipped just a bit here and there so my wiper blade was hesitating occasionally until it slipped just enough to fully stall the wiper motor due to improper timing or configuration of the linkage in respect to the motor and transmission. The continual stalling of the motor leads to the gears inside of the motor burning up.... specifically the plastic or composite gear. This is typically how these wiper motors go bad. One of the gears inside is made out of a plastic looking material and it just gets chewed up when too heavy of a load is continually applied to the wiper system ie,. turning the wipers on before clearing the windshield of a nights worth of snowfall. And of course this leads to the slipping of the linkage as explained above. 3) If you are to this point then you are also replacing your motor. Ok, there is good news here however . The good news is that a generic wiper motor can be found online for a fraction of the cost. I used one made by Vemo, which actually works very well! This item costed me $ 95.00 compared to $ 300.00 plus for OEM. I purched that part from http://www.autopartswarehouse.com and the shipping was free. The other good news is that these motors can eventually wear out just from normal use. Thus by replacing it now you save yourself the headache later. Just follow the instructions from link B and you will get it.

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[scotreeser]

I have a 2000 C230 K and my wiper motor gear got chewed up as I can now see is normal. I got a price of under $70 from http://qeautoparts.com/ The service person Dan was real helpful and had it drop ship from TX to CA instead of from FL to get it to me faster. They went the extra mile to help me out and would recomend them.

[jetmec]

I had the misfortune of my 1999 C230 wiper system go out during a snow storm last week. This was the worst time for it to happen. I did not want to bring it to the Stealer but also not sure about how to tackle the job until I found this posting. I would like to thank you so much for the great information. I needed a motor which cost 120.00 dollars. And that was it! All in all it took me about one hour and 30 minutes to change...saving huge money on the dealer...Huge thanks again...Cheers!

[maksi]

thanks amil dude!

your input is very valuable!

[Pipe]

Im looking at this sctaching my head but i dont have this problem mine just wont turn on at all.

[cellmaniac]

Does anyone have a better link to Link B?

[j-g]

My click on that link led me to ...
http://members.multimania.nl/mbenz/windshield_wiper.htm .

[99C230Komp]

99 C230 Kompressor

I followed the instructions and removed the wiper assembly as described in the following link

http://members.multimania.nl/mbenz/windshield_wiper.htm

Upon removing the assembly I found that, the nut (Yellow arrow in the image) on the wiper motor that tightens the offset plate at the back of the motor was missing. I think that may be causing the wiper to not function.

Can anyone please tell me where I can purchase this nut?

Thanks,

[mastoney]

The windshield wiper on my C230 stopped working a little while back. It has been nothing short of terrifying to drive in even the lightest rain. Hoping it was a quick inexpensive fix, I took my car to a local mercedes mechanic here in GA. He messed around with it for a minute and he gave me a quote of $500 to replace the motor. (OUCH!) Needless to say, I was not amused. I went right across the street to the auto parts store and bought another bottle of rain-x which had helped out a lot, but was not a real solution. I knew I was going to have to deal with the problem eventually. I just didn't want to cough up that kind of dough for a job that I knew I could probably do on my own. I started looking around for some DIY instructions and came across this site,

http://www.howstuffinmycarworks.com/...per_motor.html

Seeing that it wasn't really that difficult of a job, I decided to give it a go. All I had to do was find the part. I shopped all over town trying to find the best deal and couldn't find anything less than $160, which compared to the $500 i would have spent with the mercedes mechanic, wasn't too bad. I decided to look online and found some much better prices. Then I heard about this one website that just blew my mind. $26.40 for an OE replacement that included a 1 year, unlimited milage waranty. My head was spinning!!! If you don't believe me, check it out for yourself.

http://www.carpartswholesale.com/v5/...L,universal:0)

It gets even better, I used the promo code CPWcart and got an additional 25% off.

Anyhow, I just got the motor in the mail today and it only took me an hour to swap out the old one with the new one and it works like a dream!

If anybody has the same problem I had, Please don't pay some mechanic $500 to fix it. Do it yourself and save a LOT of money!

[ZachBenz]

I took Every thing apart and the linkage and gear looks ok but i was just seeing if anyone new this before i order the part.
Anyways can my wiper motor make noise and still be broke? Because honestly evrything else seems to be in good shape.
Please reply Thanks.

[ZachBenz]

Did your motor make noise and you still had to replace it.

[pc820]

I had similar issues and went through awhole lot and now it's back!!

I replaced the motor from an junk yard, also replace the wiper stick from Autohausaz and things were fine for a while until TODAY. We had snow and the wiper started sticking as it was going up. I lubed it with some grease and that fixed it but now a new issue:

The intermittent selection does not work. It will not go on. L/H work ok. What else is there to try???

[YNVDIZW124]

I replace my motor every year, I got it down to a science and can replace it in about 30mins..lol

[3400dave]

Thank you very much for the detailed info. I was able to repair the wiper motor on my 2000 C280 using your info, the two links and this additional link from howstuffinmyworks.com http://www.howstuffinmycarworks.com/...per_motor.html.
I do have one concern: The wiper returns to it's home position and then jumps up about 3-4mm. I did my best to align the mechanism per the instructions and I'm wondering if this slight offset will have an impact on the motor gear (the plastic gear in my original motor was stripped...just like in the howstuffinmycarworks.com picture). Regards, Dave

[3400dave]

Thanks for all the posts and links. I found http://www.howstuffinmycarworks.com/...per_motor.html to be the most helpful. However, now my wiper stops at the home position and then jumps up (and remains) about 3-4mm. I'm wondering if this will wear out the motor gear over time. Any thoughts? Thx, Dave

[plnfxr]

justjakinit

Thank you for taking the time to post your experience and instructions. I hope something really good happens to you.

Its dark, cold, working with a flashlight, supposed to rain the next 4 days, stressed, no other transportation. Man you made my day, I was just about ready to order a motor.

I removed the covers, lubed and the wiper works like brand new. The only difference for me was my main cover completely encircles the wiper shaft so it could only be moved over to the side. But still had plenty of room to grease.

[3400dave]

I'm still hoping someone will get back to me on the "home position issue".

Originally Posted by plnfxr

justjakinit

Thank you for taking the time to post your experience and instructions. I hope something really good happens to you.

Its dark, cold, working with a flashlight, supposed to rain the next 4 days, stressed, no other transportation. Man you made my day, I was just about ready to order a motor.

I removed the covers, lubed and the wiper works like brand new. The only difference for me was my main cover completely encircles the wiper shaft so it could only be moved over to the side. But still had plenty of room to grease.

[TeamF1Jr]

Question, the wiper on my son's 95 C280 was hesitating for 2 days and last night just stopped. Before I even start these instructions, is it worth it or is it too late now that it has stopped? It seems if I had seen these instructions a day ago I would have been able to save it, now that its stopped, I feel it might be too late. When I turn on the wiper you hear a sound like power is getting to it, but nothing is happening.

[3400dave]

It sounds like the gear in the motor is stripped. I had the same issue and bought a motor from www.autopartswarehouse.com for about $50 delivered. I followed the instructions in the link I reposted and it was pretty easy (I'm not the most mechanically inclined person but I can turn a wrench and follow instructions). Good luck. PS You can always try to lube the slides...it doesn't require much effort to pull the cover.
Question, the wiper on my son's 95 C280 was hesitating for 2 days and last night just stopped. Before I even start these instructions, is it worth it or is it too late now that it has stopped? It seems if I had seen these instructions a day ago I would have been able to save it, now that its stopped, I feel it might be too late. When I turn on the wiper you hear a sound like power is getting to it, but nothing is happening.[/QUOTE]

[TeamF1Jr]

Originally Posted by 3400dave

It sounds like the gear in the motor is stripped. I had the same issue and bought a motor from www.autopartswarehouse.com for about $50 delivered. I followed the instructions in the link I reposted and it was pretty easy (I'm not the most mechanically inclined person but I can turn a wrench and follow instructions). Good luck. PS You can always try to lube the slides...it doesn't require much effort to pull the cover.
Question, the wiper on my son's 95 C280 was hesitating for 2 days and last night just stopped. Before I even start these instructions, is it worth it or is it too late now that it has stopped? It seems if I had seen these instructions a day ago I would have been able to save it, now that its stopped, I feel it might be too late. When I turn on the wiper you hear a sound like power is getting to it, but nothing is happening.

[/QUOTE]

Thanks for the quick reply, I'll report back with results for others on the board.

Phil

[TeamF1Jr]

Just wanted to followup to my earlier post that everything worked great with no replacement parts necessary. The wiper motor was operational as I could hear it, but the wiper wasn't moving. I followed this video to the point where he mentions the same problem I had at point 10:49 in the video and sure enough followed the tightening recommendation and bingo it works again. Although this guy rips through the disassembly, between my son and I it took much longer, but we got it done and saved my son a few bucks.

You Tube

You Tube

[edchris]

Great DIY help. I'm in the same boat, regarding my daughters 1997 C230. The wipers totally quit on the way home from university.
I pulled the covers, lube is fine, I can actually swing the blade assembly to/fro quite easily by hand, it moves readily in the "W" path. This leads me to believe the connecting nut has come off the back, or gear motor stripped.
I have one additional problem. I only seem to have power to the wiper motor in 1 position of the wiper/signal selector. Only in the 3rd position do I hear the wiper motor turn. All other positions are dead. Should the motor turn in all positions of the selector arm?
Can anyone tell me, is this a problem with the actual selector? Bad wires/switch. Or is this a symptom that turns up when the motor goes bad. Are there contacts in the motor itself that would cause this?
I'm going to check for a disconnect between motor & transmission,(bevel plate?), but before I take it apart I'm wondering if I need the motor & the actual selector arm(what you use inside the car to turn wipers on/off). If selector arm replacement is needed, is that a tough job, due steering wheel airbags etc?
Thanks.

[YNVDIZW124]

gear motor stripped.

They're made of plastic, this always happens. I wish the sold replacements.

[3400dave]

Turn the wiper position to the first (slowest/lowest setting) and manually "help" the wiper move thru it's "W" path...it should work with a little help: I doubt you're having issues with the interior selector switch on the arm. The gear/disc in the motor is probably fried. It's pretty easy (following the DIY vid) to pull the motor and verify. Good luck!

[edchris]

3400Dave. Thanks. I think the gear is totally strpiped as I can grab the wiper arm & easily move it to/fro. It moves in the "W" shape, so I think the transmission is OK.
What concerned me was the actual motor only energizes in position III. I can hear the motor turning with the slector in that position, all other positions seem totally dead.
The links in this forum are excellent, & will save me $$$ from the dealership here in Canada.