I have noticed on some days when the sun is out and bright and its as clear as can be, my headlights will turn on. What is up with that? I keep my headlights in auto-on mode. I don't see any shadows or anything blocking the sensor either. And I keep my windows relatively clean with Invisible Glass. Has anyone else experienced this?

 

yes its just the auto mode. it's straight

 

umm but why do they turn on on a clear day? its not overcast or gloomy or anything. its a super duper clear day i tell ya. i don't get it.

 

Not sure what your car specs are but do you have DRL's?

 

This might explain it (from my owner's manual) ... Yes, I too find there are times the LED indicates my headlights are on but it's not "dark".

 

Mine do the same - at times indeed they will come on in broad daylight when the sun is high above and bright. I'd like to think there is some real intelligence behind it, like they come on to make sure that the car is seen in bright glare, etc., but I think the sensor logic is just a tad bit screwy.

There is a sensitivity setting that you might want to have the dealer change - I have not worried about it.

 

Yes I have noticed that the angle of the sun seems to be a factor as my headlights tend to turn on when the sun is high and bright but not while it's at an angle. I tend to think it would do the opposite because at a certain angle, one would gather that it is nearing either dawn or dusk.

 

Yes mine comes on around 4 o'clock when the sun is at an angle. I think they do this because if the sun is behind you, incoming cars on the opposite side may be blinded by the glare so it is a lot safer to have the headlights on so people know you're there. Also for cars in front of you they may also be blinded by the glare when they look on their rear view mirror so if you have your lights on they can see you better.

During overcast around midday the auto light rarely comes on because it knows it isn't dark enough to come on.

 

I have also noticed my lights coming on in bright daylight. The Autolamp on my 2000 Ford Explorer does a better job of controlling the headlights than the automatic control in my 545i.

 

Check out this recent thread and my post that points to some older threads about all this:
https://5series.net/forums/topic/109...n-its-not-dark