I've checked the threads, and didn't find an answer to my question about rain sensing wipers, so I thought I'd post a new thread. I know mine are working, to a degree. (I.E: When its not raining, my windshield wipers are off, and when it is, they go.) However, my question is to the degree they are working. It seems that even if I am in a drizzle, the wipers remain on, with no intermittent operation whatsover. Every once and again, when I first turn the wipers to this option, the wipers will wipe, then stop for an interval (the way I figured this option is supposed to work) then wipe again in light rain/drizzle, only to then begin running all the time. But most of the time its like the wipers are on all the time, no matter how much, or little it is raining. Could I have a faulty sensor. I still have the original windshield, so that should not be an issue, and the glass around the blue sensor is in perfect condition. I'm wondering if this is a widespread issue. I myself have never Rain-X'd the windshield.

It seems to me that you have a problem with the sensor. Mine works perfectly It works just like I would want it to work if I were operating it manually. In fact when I fist bought the car, I was suprised the system worked so well.

My experience has been like Billc's, both the 2001 e and the 2002 c worked as well as you could do by hand. If it stopped raining while the system was on, the wipers would no longer run at all.

Then last week my 2002 c began doing exactly what Clemson91 describes - when you first turn on the wiper the system is fine, ie you'll get one or two occasional wipes. Once the windshield has been rained on the wipers switch on permanently, and don't stop till you shut them off. Driving into the garage on a rainy day is a good test - they used to shut off, but not anymore.

The c goes in next Friday for its "A" service, and they will look at this also. I'll post the outcome...

Hi. My C43 just started doing the same thing. It wipes intermittently once in awhile, then will run constantly for awhile. I tried cleaning the glass and the blade to remove any streaking.

Did you ever find out what was causing your problem?

Thanks,

John

__________________
'99 AMG C43

I just got back from a long road trip with my C320. I really like the auto wiper option. It works very well. I did notice that in conditions where it isn't wet enough to self clear road grime like salt off of the windshield, the sensor will cause the wipers to continue wiping. Using windshield washer fluid clears the grime from the windshield/sensor and the wipers return to normal sensor operation. In my opinion, a very accurate sensor. This may sound like a pretty basic question but have you tried cleaning the sensor area with window cleaner?

I'm having a similar problem up here in wet ol' Washington State. When I first got the car (3 months ago), the rainsensor feature worked perfectly and the windshield was crystal clear. I think the dealer must have put a new blade on.

But now all I get is a big smear and it's nearly impossible to see at night, besides the fact that the rainsensor wipers seem overly active.

It seems that the auto function wipes more if there is smearing on the windshield. I can't figure out how to keep the smearing off! Am I using the wrong (aka "cheap") washer fluid? What's the best way to a smear-free windshield?

__________________
2003 Hyundai Santa Fe, Silver
1999 C280 Sport, Black
1997 Ford Escort, Toreador Red

My rain sensor will not go into MAX speed no matter how heavy the down pour is. However, it works ok in drizzle. The new design incorporates light sensor which will increase wiper speed at night. Check out www.hella.com

Car Nut
99 E430 Sport

Well, here is an update on my 2002 c320. It went in for the A service, and the dealer "reset" the rain sensing option. It seems to have made no difference - sometimes it works great, and other times it will run fine for a while (maybe 15 minutes), then switch into an "always on" mode. The system on the e320 always works fine (sure hope I don't jinx it!).

Thanks to "Car Nut" for the link to Hella - I did not know this module was made by Hella. It was interesting to see how the system works.

Sometime soon I'll make a return appointment to have this looked at again - this is too cool an option to allow it to stay broken.

__________________
2001 e320 wagon
2004 F350
2006 Crown Vic