[cableguy]

I have never had rain sensing wipers before so am unfamiliar with how they SHOULD work. I have had read that they can be a bit unruly, not working as one would want.


Today I set them on the most sensitive setting as it was raining continuously but not heavily.


The pattern was 3 wipes with about 5-10 seconds between each, followed by around 30-45 seconds with no wiping. During the 30-45 seconds more rain would accumulate on the windshield that desirable.


Is this normal behavior? Since there's no simple intermittent setting I would like to have the rain sensing setting work better.


Or am I missing something?

 

[Otto]

Have you adjusted the sensitivity to see how that affects the things? Best way for us to help you is to see a video.

 

[cableguy]

Yes I've tried it from the most sensitive to the least sensitive. If the "most sensitive" setting is not sensitive enough and allows more than desired rain to collect...not sure where to go from there. I'd prefer fixed intermittent settings to this. I will see if I get another chance to try other settings to compare more closely but need the right amount of rain to do that...I don't drive that much.

 

[rnlabas]

Actually it sounds like you are already using the fixed intermittent settings - if a regular rain pattern is sensed, the "sensed" wipe will be continuous at either normal or fast setting NOT intermittent at all ...only if there is NO moisture and the stalk is set will a "sensed"wipe be intermittent -

 

[cableguy]

Sorry Roger but I'm not getting this.

Here's what it says in my manual: "Interval mode. To extend/shorten the wiper intervals, move the switch to the left/right. In vehicles with a rain sensor [which I believe I have with the Prestige model], the wipers turn on in the rain once the vehicle speed exceeds approximately 2 miles per hour. The higher the rain sensor sensitivity is set, the earlier the windshield wipers react to moisture on the windshield."

So I have the switch set all the way to the right, which should provide maximum rain sensitivity and it it sounds like this also provides the shortest interval. But if so, then why, when I have it to the far right setting, am I getting a pattern of 3 wipes close together, with a 30 or so second gap with no wiping action, during which rain collects on the windshield? That pattern makes no sense to me.

Thanks
John

 

[rnlabas]

I don't believe even the longest extended interval setting (non-rain sensing) is 30 seconds, maybe more like 3-5 - but anyway, I also think the rain sensor sensitivity is the MOST sensitive when set to the right (towards the longer marks), just as is the shortest duration of the interval setting. You can tell if you have the rain sensor by a big black mount under your rearview mirror (about 3" diameter) - but I believe the Prestige models have it anyway. The MOST sensitive rain sense wipe will start when the car is moving AND there is about 5-10 drops per square inch on your windshield - or at least the sensor area. If the rain is uneven (like just one side of the windshield for example), it prolly won't work consistently. Perhaps your sensor is bad or malfunctioning - it's possible.

 

[e85sbm]

The rain sensor is something that is not easy to explain. It uses a number of variables to determine when to wipe and when to rest.

Basically - if driving is steady rain, they will wipe constantly (provided you are driving are a constant speed). The faster the speed, the more the sensitivity is adjusted. Should you stop at an intersection, the rate of wipe will decrease or stop as a result of the wheels not turning and you not needing as much forward visibility.

One way that I learned about the reaction of the wipers was driving next to semi who splashed a large puddle onto my car. The wipers went to super fast wipe mode for 3 or 4 cycles, then returned to a slower, more regular pattern.

Hopefully this adds a little extra clarification. Rogers was more detailed.

 

[cableguy]

Thanks. Based on the above it sounds like I may have an issue. I'm going to run some test, once I can use the hose in the driveway...too cold to do that now.

 

[Quatto]

The rain sensor is something that is not easy to explain. It uses a number of variables to determine when to wipe and when to rest.

Basically - if driving is steady rain, they will wipe constantly (provided you are driving are a constant speed). The faster the speed, the more the sensitivity is adjusted. Should you stop at an intersection, the rate of wipe will decrease or stop as a result of the wheels not turning and you not needing as much forward visibility.

One way that I learned about the reaction of the wipers was driving next to semi who splashed a large puddle onto my car. The wipers went to super fast wipe mode for 3 or 4 cycles, then returned to a slower, more regular pattern.

Hopefully this adds a little extra clarification. Rogers was more detailed.

I bet it has some sort of frequency of water droplets it adjusts for.

 

[cableguy]

Perhaps - but what I don't understand is that it seemed to follow a pattern Vs simply sensing water and reacting to it. It was 3 wipes with about 10 seconds between them and then more like 30-45 seconds before another set of 3 wipes.

 

[rnlabas]

...with constant rain falling - or did the 3 wipes clear most (all) of it for the 30-45 secs ?

 

[cableguy]

this occurred during a consistent but light rain. The windshield was pretty water free after the first sweep of the wiper, so the next two sweeps weren't even needed. Then during the 30-45 seconds before another wipe, enough water collected on the windshield that it was negatively affecting visibility in my opinion. So the pattern doesn't make sense. It would make sense if the wipers did more evenly spaced sweeps under a constant but low volume rain.

 

[FuturePerfect]

cableguy: I have a similar or the same problem in my 2016 Prestige. But I haven't documented it as well as you. I just know that sometimes there are long visibility-reducing delays in the intermittent wiper movement, regardless of how I've set it. Frustrating.

Would turning off the switch on the rear-view mirror (for auto dimming) also turn off rain sensing? This just occurred to me so I haven't tried that yet (I currently have auto-dimming on) and Roger mentioned the rain sensor is on the Prestige mirror mount.

Or, am I correct in understanding there is no toggle somewhere to turn off rain sensing?

Would appreciate any updates on progress with this problem.

Also, do you have another problem I have--your wipers jumping up slightly from bottom of windshield when turn engine off (or on?)?

 

[rnlabas]

cableguy: I have a similar or the same problem in my 2016 Prestige. But I haven't documented it as well as you. I just know that sometimes there are long visibility-reducing delays in the intermittent wiper movement, regardless of how I've set it. Frustrating.

Would turning off the switch on the rear-view mirror (for auto dimming) also turn off rain sensing? This just occurred to me so I haven't tried that yet (I currently have auto-dimming on) and Roger mentioned the rain sensor is on the Prestige mirror mount.

Or, am I correct in understanding there is no toggle somewhere to turn off rain sensing?

Would appreciate any updates on progress with this problem.

Also, do you have another problem I have--your wipers jumping up slightly from bottom of windshield when turn engine off (or on?)?

The rain sensor is a part of the mirror mount which is flat against the glass. There is no toggle switch for the rain sensing other than the stalk. Intermittent cycling is completely separate from rain sensing.

The wipers do a periodic "reset" of park movement and positioning about every 3rd or 4th on-off car cycle - this is normal as has been discussed here in several places - all Audis (and most BMWs & Mercedes) do this.

 

[FuturePerfect]

Roger: Thanks for your explanations. Since both cableguy and me have the problem as described in post #12 (and I confirm I have pauses in intermittent mode of 30-45 seconds), do you think we have a wiper control defect? Or am I confused about how to prevent this?

 

[cableguy]

I had another chance to review performance of rain sensing function on my 6 mile drive to work today. There was a fairly steady but not heavy rain during the drive. Once again the performance of the wipers was concerning. The general pattern was similar to before: several wipes within about 5-7 seconds of each other followed by a long pause. During the long pause the windshield becomes quite filled with drops, reducing visibility. Sometimes I'd get two, or 3 or even 4 wipes with the 5-7 second separation before the long pause.


If this is a defect condition, I'm happy to report it at my 5k check up. If this is the way the wipers work on rain sensing then I'm wondering if there's any way to eliminate the sending and just have a fixed intermittent wiper with several different lengths between wipes. That would be much better than what I'm getting now.

 

[AMILL]

Hi John
I addressed a similar problem with my wipers to the dealer. They told me it's just a characteristic of the Audi and there is nothing wrong with the wipers. I agree with you though after having a BMW x3 those wipers had quite a lot of settings to get it to address even the slightest rain. They worked when there was rain and DIDN'T work when there wasn't any.

It drives me buggy when the wipers go off and there isn't a drop of rain on the windshield and when the rain builds up there doesn't seem to be any action. BTW, don't know if you noticed it but the rain sensor seems to react more over 40mph. I hope in the near future they can find a fix for it.

 

[cableguy]

Thanks AMILL, I appreciate the confirmation...that's the answer I anticipated.

I had another test of the wipers on the way to work late last week where it was raining just a bit harder than before. I did not change the wiper setting and yet it was apparently just enough additional rain volume that the wipers swiped every few seconds almost all the way to work and the pattern remained pretty constant. In that circumstance they performed as I would have expected them to. So it appears that they under perform in lighter rainfall and that's just the way it is. Well as we all know, no vehicle is perfect and if this is the worst characteristic I have to deal with I'll be happy... Thankfully we live in an area that doesn't get that much rain and when we do it's generally more than a drizzle. Now if I was living in Portland OR I might be more concerned as there are many rainy days and often it's a light rain. Of course if I was living in all that rain I'd probably have more concerns than just my car wipers....

 

[rnlabas]

ALL - I have an early NAR Q3 (Oct 15) and just having driven from Florida home thru rain - used these. They worked pretty well imho - only letting about 30% of the windshield covered before swiping and when clear, resting dry until another 30% or so was covered. They worked well in intermittent and up to full speed in varying rain - all this over about a 650 mile trip thru dry, sprinkles and VERY heavy rain. Perhaps there is another fault somewhere, but mine seemed to do exactly as I would expect of them.btw, I had NO 2-3 swipe then stop episodes at all with them -