Wiper Operation

[MIW615]

Hi

I have recently acquired a 4 year old E240 Avantgarde and have a question for one of you technical guys.

When I select the intermittent position on the wiper switch sometimes the wipers work intermittently as I would expect and other times the wipers run continuosly. Does my car have a rain sensor that could cause this and if so where is the sensor, or could there be a fault with the intermittent relay and if so where is this located?

Thanks in advance for any help / advise given.

Cheers

MW

 

[996jimbo]

It sounds as if you have rain sensing wipers.

Assuming you do, the sensor is up behind (or ahead of) the rear view mirror - it's a blue patch you can see through the windscreen. It works by judging the refraction through the windscreen as it is altered by water ie if it is raining and how much.

Unfortunately you cannot calibrate it yourself and there is no variable calibration. You have to go to a MB or specialist and ask them to look at it.

Mine originally did exactly the same as yours. I had it checked and it was actually disconnected. After it was reconnected I was not happy with it and had it recalibrated.

As an aside - Alfa have rain sensing wipers and you can vary the sensitivity by 3 settings - much more user friendly than the MB system.

 

[MIW615]

It sounds as if you have rain sensing wipers.

Assuming you do, the sensor is up behind (or ahead of) the rear view mirror - it's a blue patch you can see through the windscreen. It works by judging the refraction through the windscreen as it is altered by water ie if it is raining and how much.

Unfortunately you cannot calibrate it yourself and there is no variable calibration. You have to go to a MB or specialist and ask them to look at it.

Mine originally did exactly the same as yours. I had it checked and it was actually disconnected. After it was reconnected I was not happy with it and had it recalibrated.

As an aside - Alfa have rain sensing wipers and you can vary the sensitivity by 3 settings - much more user friendly than the MB system.

Thanks for prompt reply, I will check for "the blue patch"

Cheers

MW