Rain sensor logic?

[Price]

It was raining hard recently here in VA and I've noticed a strange thing in our new 08 X3: if you have wipers in auto mode and it's raining, they won't resume operation if you stopped and turned engine off and then back on (say you stopped for gas). Your windshield can be all covered with drops but wipers will be motionless untill you actually move the lever down to OFF and then back up to AUTO, only then they resume working.

I have rain sensor in my other car (LR3) and never experienced such a behavior. What is the sensors' logic? Is it reacting only to a difference, i.e. if you windshield is covered with drops already before you turn on ignition, it won't activate the wipers?

[motordavid]

All the Xs have that built in; so, if you left the auto/rain sensor in "on"
mode and drove through a car wash, they would not come on and get
damaged from the brushes and drag mats.

Give the ol'manual a read; it talks about it in that special black book
that is seldom cracked open.
GL,mD

[statdoc]

Originally Posted by motordavid

Give the ol'manual a read

What, are you freakin' crazy?????

[Price]

and yes indeed, page 42 does reveal the secrets of wipers operation...

[rayxi]

Originally Posted by Price

and yes indeed, page 42 does reveal the secrets of wipers operation...

Now that you've read it you too can answer 95% of the questions posted on this board.

[AzNMpower32]

That's normal for all BMWs; you must reactivate the rain sensor. On the newer BMWs, you just push a button each time so its more intuitive. On the older BMWs you have to either do what you do with the stalk, or turn the serrated dial.

[vern]

Originally Posted by rayxi

Now that you've read it you too can answer 95% of the questions posted on this board.

+ 1 But some feel its easy to ask rather than to read
cheers
vern

[judybe83]

We didn't like the rain sensor, always seemed to wait too long between wipes or wipe when there was almost nothing to wipe, so we had it turned OFF.


Later I read that some (all) early X3's had a problem with the rain sensor.

Now rain sensing wipers seem like one of those REALLY good ideas that in REAL life "just didn't work out the way we thought it would".

ab