Although it's true that original 545i didn't have a DRL setting in the idrive, it does get it with a software update. I upgraded to 32.1 and when I did, I magically got a DRL setting.

The DRL setting is totally related to the automatic lights setting you're talking about.

DRL off + Switch in auto mode = lights come on when it's dark.

DRL on + Switch in auto mode = lights are on all the time when the ignition is on.

The behaviour you described would happen if DRL was switched to on. Maybe you did it and didn't realize it was related to the auto-lights switch, or the kids did it.

I have my switch in auto mode all the time. During the winter I have my DRL switch set to on. The other half of the year I have DRL set to off.

 

Thank you for the tips on settings, that made a lot of sense. I wanted to post the final thing that fixed my issue of my headlights turning on in the middle of the day.

There were tons of great points given throughout the forum, and I read all of them.
After reading a totally separate thread on replacing the car battery I realized that I had a bad-weak battery. I went to my mechanic and he replaced and programed a new one. After that for whatever reason my daylight autodetect starting working again. No idea why but everything is working again.


So maybe some of "those funny" things we seem to see when dealing with software and electronics could be related to a weak or battery that was installed but not programed to the car?

 

Or maybe the act of replacing the battery (disconnecting the power to the car) caused things to reset/reboot and clear any glitches that were present?

Either way, glad it's now working better for you...