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Ry"c
01-09-2011, 03:58 PM
RE: Wiper Rain Sensor Sensitivity
The manual only says, "turn the thumb wheel," to adjust the sensitivity. It doesn't say which direction is more sensitive and which direction is less sensitive. The icons on the stalk are one arrow downwards and two arrows upwards, which doesn't explain to me what it means.. Please answer: when which direction makes the wipers sweep with more water on the windshield and which direction makes the wipers sweep when the windshield has less water droplest on it?
Thank You

markl53
01-09-2011, 05:05 PM
UP toward two bars means more wipes, more sensitive. 2 bars = more wipes, 1 bar = less wipes. Although with my previous 335i, the sensitivity adjustment didn't make a drastic change. I haven't had a chance to check it fully in my new 535i. I suggest checking the difference between the lowest position (least sensitive) to highest position (most sensitive) to see how much change you notice. Clicks between adjacent positions may not make much difference. And when you switch from a lower to higher setting, it causes an immediate wipe since it figures you might be making the change for conditions at that moment. Changing from higher to lower does not cause wipe.

Rafa
01-09-2011, 06:09 PM
UP toward two bars means more wipes, more sensitive. 2 bars = more wipes, 1 bar = less wipes. Although with my previous 335i, the sensitivity adjustment didn't make a drastic change. I haven't had a chance to check it fully in my new 535i. I suggest checking the difference between the lowest position (least sensitive) to highest position (most sensitive) to see how much change you notice. Clicks between adjacent positions may not make much difference. And when you switch from a lower to higher setting, it causes an immediate wipe since it figures you might be making the change for conditions at that moment. Changing from higher to lower does not cause wipe.

Very well said.

I have a question of my own, which might seem stupid but I have not driven under snowy conditions in many, many years. Will the auto wipers work in snow the same as in rain? I would think so, but it doesn't hurt to ask just to be sure.

markl53
01-09-2011, 07:23 PM
Very well said.

I have a question of my own, which might seem stupid but I have not driven under snowy conditions in many, many years. Will the auto wipers work in snow the same as in rain? I would think so, but it doesn't hurt to ask just to be sure.

I'm pretty sure I've driven in snow with my 335i. It should work fine since it detects "stuff" on the windshield. On a heated windshield the snow probably turns to water drops pretty much too. Also if you have worn wiper blades that smear, that can cause unneeded wipes because the sensor thinks there is still water on the windshield. I had this issue more with my older MB than any of my BMW's.

Rafa
01-09-2011, 07:41 PM
I'm pretty sure I've driven in snow with my 335i. It should work fine since it detects "stuff" on the windshield. On a heated windshield the snow probably turns to water drops pretty much too. Also if you have worn wiper blades that smear, that can cause unneeded wipes because the sensor thinks there is still water on the windshield. I had this issue more with my older MB than any of my BMW's.

Thanks for your reply, Markl53.

A little bit off topic... When did auto wipers come into widespread use? I know I could google it, but...

markl53
01-09-2011, 07:46 PM
Thanks for your reply, Markl53.

A little bit off topic... When did auto wipers come into widespread use? I know I could google it, but...

Well my MB was an '02 C-Class. By then I think they'd been around for a couple years on higher end models. I'm still "shocked" that our '08 TL doesn't have them. Some people don't like them and if they aren't working right (old blades, etc) they can be a pain. But overall they're so much better than regular variable intermittent. And my 335i would switch from intermittent to full low speed all the way to high speed depending on the rain, it was quite impressive I thought. I just haven't driven the 535i enough in rain to know if they're any different.

Rafa
01-09-2011, 07:53 PM
Well my MB was an '02 C-Class. By then I think they'd been around for a couple years on higher end models. I'm still "shocked" that our '08 TL doesn't have them. Some people don't like them and if they aren't working right (old blades, etc) they can be a pain. But overall they're so much better than regular variable intermittent. And my 335i would switch from intermittent to full low speed all the way to high speed depending on the rain, it was quite impressive I thought. I just haven't driven the 535i enough in rain to know if they're any different.

I have driven my F10 in the rain quite often, starting with my ED. The auto wipers work just fine, as well as in any other car I've driven with the feature. If you are like me, you'll fiddle with the sensitivity setting, but not because of any defect in the system.

Ry"c
01-09-2011, 08:19 PM
UP toward two bars means more wipes, more sensitive. 2 bars = more wipes, 1 bar = less wipes. Although with my previous 335i, the sensitivity adjustment didn't make a drastic change. I haven't had a chance to check it fully in my new 535i. I suggest checking the difference between the lowest position (least sensitive) to highest position (most sensitive) to see how much change you notice. Clicks between adjacent positions may not make much difference. And when you switch from a lower to higher setting, it causes an immediate wipe since it figures you might be making the change for conditions at that moment. Changing from higher to lower does not cause wipe.

Are you sure? The arrows could refer to the amount of water--two arrows is more water and one arrow is less water, meaning the two arrows (upwards) direction causes the wipers to sweep when there is more water and the one arrow position (dowwards) causes the wipers to sweep when there is less water droplets on the widnshield. This is exactly opposite of what you posted. Do you work for BMW or otherwise have some inside knowledge?
Thank You.

Rafa
01-09-2011, 08:34 PM
Speaking from experience, markl53 is right. There is no need to be a BMW insider to know what he is stating in his post. Markl53 is a well informed, judicious person IMO, so I trust the veracity of his posts. Sure, he could be wrong, but not on this one. I believe other posters will concur.

salamigs
01-09-2011, 11:00 PM
There is an easy way to figure this out (well I know the answer but I will walk you through the steps to better ensure you all):
1. Set your sensitivity to the middle while the wipers are off.
2. Turn your rain sensing wipers on, regardless of water on the windshield, it should wipe once.
3. Now change the sensitivity to one direction of your choice; if it wipes immediately (again regardless of the water on the windshield), you just increased sensitivity. If it does not, then you decreased it. Try the other way, and you will see the opposite behavior.

markl53
01-10-2011, 06:39 AM
Are you sure? The arrows could refer to the amount of water--two arrows is more water and one arrow is less water, meaning the two arrows (upwards) direction causes the wipers to sweep when there is more water and the one arrow position (dowwards) causes the wipers to sweep when there is less water droplets on the widnshield. This is exactly opposite of what you posted. Do you work for BMW or otherwise have some inside knowledge?
Thank You.

I see others responded already. I've owned 3 BMW's with the rain sense feature so I know what the bars mean from my own trial and error. It's easy enough to try it for yourself next time it's raining and report your own experience if it differs.

laser
01-10-2011, 07:38 AM
Very well said.

I have a question of my own, which might seem stupid but I have not driven under snowy conditions in many, many years. Will the auto wipers work in snow the same as in rain? I would think so, but it doesn't hurt to ask just to be sure.

Like most things in life "it depends" .....

Driving in Colorado high country with dry snow and cold temps drivers value a frozen windshield which just lets the snow blow off the cold glass - no defroster allowed here.

Wet heavy snow in a warmer condition closer to 32 temp will melt on the windshield and water will trigger the rain sensor.

I won't test this in Atlanta today with 8 inches of snow the only driving will be in my son's old Land Rover Disco if we need emergency replenishment of supplies for tonights BCS Championship game!