dme327

I own a 2009 MB E350:

And, on several occasions, my automatic windshield wipers have automatically begun to operate, even though the weather was "clear and dry" (no rain).
Interestingly, in contrast, the opposite has occurred several times. It begins to rain … but the windshield wipers do not go on automatically.

Has anybody else ever had that problem ?

rodneypierce

Mine does this all the time at random. But mine usually always activate when it starts to rain.

dme327

Thank you. Somehow, it always feels better when you’re not alone !

rodneypierce

haha, for sure! Its annoying. Ill be driving down the road, sunny hot summer day; not a cloud in site. And bam, wipers kick on.

Azeem

Was the windshield ever replaced by you or previous owner? The rain sensor is located just behind the back view mirror (top center of the windshield). Have it cleaned or else you need to calibrate the functionality using Star session.

ot1

How many strokes does it do when it kicks on? If its just one or two then no worries, because rain isnt the only thing that can trigger the wipers, could be birds crapping, mist kicked up from wind in trees or a reefer truck defrosting down the highway, a goofball spitting out the window in front of you, or a hundred other maybes. But if it comes on and stays on without rain it has an issue. On very rare occasions my wipers wont trigger with light rain so I have to switch them off then back on but there after they work properly, speeding up in heavier rain too. They work well especially with the MB blades 2118202945

rodneypierce

When it happens, they run until I reach down and turn the switch off. Usually I can click it right back to auto and its fine after that.

ot1

Do you park under trees? Some trees mist a sap that could fool your sensor, and the sap stays on the window even after multiple wipes, I know its a long shot.

rodneypierce

Nope, open parking lot. No trees.

Bankroll

Don't leave the wipers in "auto", unless it is raining. Don't switch from off to auto, unless the windshield is wet, to avoid scratching a dry dirty windshied.

dme327

Well, that is certainly a lot different than my 2009 Toyota Avalon !!!

But, live and learn !