About a week ago I started to notice a progressively worsening hesitation on the wiper cycle on my 2000 c280. Murphy's Law kicked in as a severe thunder storm developed, and wiper stopped working completely (I now see it as punishment for car-neglect).
Anyway I digress. I searched on the intertubes and found this forum and its many posts of people with the same problem. It was bittersweet seeing so many people with the same problem. I saw solutions ranging from re-lubing parts (202Tech - Hesitating Wiper Fix
) to a total replacement of the wiper motor/transmission assembly, and I also saw that Merc dealership would fix it for a messily 1200 dollar (HOLY SH!T!). So empowered with the drive not to get boned by the dealership I set to work.
I figured since the wiper had totally quit moving, this wasn't going to be a simple lube-job. Instead I assumed it was the stripped gear problem. I started with trying to remove the wiper arm....and after lots of head scratching I decided i didn't have proper engineering degree to successfully disessmble the arm housing. Accepting defeat, I started on the removing the "air-dam" plastic (10 phillips screws, 2 10mm bolts). With the plastic out of the way, I had easy access to the motor/transmission, and all the nuts and bolts securing the assembly to the car. I removed the top cover of the transmission (six t20 torx screws) to get access to the infamous gear, and it was, to my surprise/elation/confusion, in pristine condition..... After further investigation I noticed the linkage was no longer connected to the transmission. I removed the entire wiper assembly with the arm still attached (1- 10mm bolt, 2-10mm nuts, 1 rubber gromit). Once the assembly was out of the car, I see it was missing the 13mm nut that connects the linkage to the transmission. Before heading out to the hardware/automotive store, I looked down into the recesses below where the assemble sits and found the bolt (WOOT!!). I refastened the bolt with some lock-tight, reassembled everything, and it works like a dream. FYI...i still do not know how remove the wiper arm.
Sorry for being so long winded. Hope this helps some one.