Intermittent fault - Windscreen wipers W205 Mercedes C Class

[romeogolf]

The current C-class has four modes of operation for the front wipers. The first two cover the auto-sensing wiper function.

(i) Low sensitivity auto-wipe
(ii) High sensitivity auto-wipe
(iii) Constant slow
(iv) Constant Fast

In any of the first three modes, after a short time of use (less than 15 minutes) the wipers 'lock out' of constant mode. For example, in steady rain, I might have the stalk set in position (ii) and the wipers will move constantly. Then, with no noticeable change to the weather, they switch to a moderate intermittent wipe.

I'll usually notice this quickly as I can't see, and I move the switch up to position (iii), but there is no change to the wiping. They remain on an intermittent cycle. Pushing the switch to (iv) puts the wipers onto the "constant fast" setting which works, and I can then switch back down to (iii) and the wipers carry on in the 'constant slow' setting. After another 5 to 10 minutes they again go back into an intermittent wipe, the only way to get them constant again is moving the switch up to (iv) and back down.

I've double-checked the manual, and I am correct in my understanding of the four modes. I have reported this to the local MB dealer and it's been booked in to be investigated (soonest appointment 3 weeks away...) but they've never heard of this before.

Has anyone else had a similar issue? Sounds like a software thing at this point.

[iceyfuel]

Have you ever had the windscreen replaced? Sometimes doing that can knock the sensor out of whack.

[romeogolf]

iceyfuel said:

Have you ever had the windscreen replaced? Sometimes doing that can knock the sensor out of whack.

Nope, never had it replaced.

[Aki012]

Hi

Have you managed to sort out your wiper fault. Mine have starter to play up and now the first auto wipe setting comes on once when i switch it on. The secone auto setting only comes on 1 or 2 times after 40 or 50 seconds in heavy rain.