Hey everyone, first post here! Looking for some help with this diagnosis and repair.

I have a 1999 C230K (this is my 2nd W202, I had a 2000 C230K some years ago), it's in pristine condition with 100k-ish miles. It has a few gremlins to work out, one of these things is the front windshield wiper wants to park at about 11 o'clock position, on any wiper setting--this car has one intermittent, low, and high. All three settings, the wiper drags / gets stuck for a moment around 11 o'clock and then continues, and returns to park without stopping.

I disassembled the wiper cowling last night and looked at the worm gear and contact points. The contact points were a little worn, not bad. I sanded them a bit with some 300 grit sandpaper, and bent them a little to give them better contact with the worm wheel gear contacts. It appears to be making good contact. I then lubed the worm wheel gear and contact points with dielectric grease. While I had it apart, I removed the whole wiper assembly and inspected the linkage. Everything appears to be good, nothing bent or corroded. I did not disconnect the motor and move the whole array to check for binding (although this might be my next step), I just assumed the contact points work would solve it.

Upon reassembly, it still has the same behavior.

Could it be the wiper motor failing? I assume if it were, the symptoms wouldn't be in the exact same spot in the wiper travel each time.

Perhaps the linkage needs lubrication and is binding up? I'm wondering if this is a common thing. The linkage honestly looks good and still had some grease and lube at the joints.

The other thing I noticed is the aluminum mounting bracket for the wiper assembly had a lot of play and movement in it as the wiper actuates. Could the play and movement be causing the plastic worm wheel gear to move up and down in the housing and lose contact briefly with the contact points? I assume the contact points should have contact throughout the travel because I really gave them some bend toward the worm wheel gear to counteract the potential that they're losing contact briefly.

If anyone ahs had experience with this and has any suggestions on diagnostic and repair, I'd appreciate it. Thanks!

Internals of the contact points and worm gear look very good in my opinion.

 

According to Grok, this is extremely common on W202 C-Class (1994–2000).The wiper motor has an internal park switch (a cam and contact inside the gear cover) that tells the motor when to stop in the "park" position.
Diagnosis = Bad wiper motor (park switch or gears)
Fix: Replace the Wiper Motor
Only if motor replacement doesn’t solve it:

• Check ground wire at motor (corrosion)
• Test combination switch (rarely causes park failure)

This was my query:mercedes 1999 c230k wipers randomly stop at 11 0'clock position

 

Following up for future people reading about this.

There's a nut on a threaded, conical splined piece that connects the powered actuator to the linkage in the wiper transmission. The nut had come loose, resulting in not enough pressure holding the linkage down onto the conical splined piece. It just required tightening the nut.

I went ahead and took care of all the linkage points that needed grease, and cleaned the circular contact points as well, just because I was in there.

For what it's worth, the Grok query from w202.029 was nearly useless here. Way to use AI and provide zero value. 👍🏼

 

lmao I hate AI