My drive to work is short, like 10min, that's every weekday.

A couple recent changes to routine; car parked at airport for a week, but that was last month, however I remember the windows were really slow to roll down when I did it from the key fob while approaching the car, it started but it did seem like a little low battery. Maybe that is when it started.
Just before the trip to the airport, I got a drive recorder (dash cam), which plugs into the cig lighter under the passenger side dash/foot well. I've wondered if it somehow drains battery when off but I doubt it as the cam turns off when the car shuts off. (i remember someone talking about cig lighter power not turning off in a 3 series forum)


I just thought of another symptom, since around the first time I saw the time reset, I've noticed that when unlocking the car at night, only the pathway lights under the mirrors light up, the head lamps and tail lamps do not light up anymore. All the options in idrive for lighting are on.

 

How old is the battery? Sounds like the issue to me

Mine popped up "alternator failure" when alt. was going out..

 

I need to check out the battery then. I don't know how old it is. I've only had the car for 3 months, took it to BMW and had them check history and I got to see all the prior maintenance work, etc. and the only power related fix was a "battery power cable" replacement, but that's the extent of it. I looked at the battery once when I had the trunk carpet out while changing to M5 springs, and I noticed it had the little green indicator but I don't remember the date on it. I'll do it this weekend.

 

What year is the car?

 

10 min drive will just not charge the battery enough, especially when battery gets older, also it will ruin a new battery fast.......also will be hard on the alternator.....you need to drive more or put the battery on a battery tender/minder overnight to keep it fully charged. These cars are power hungry!!!AND like this guy in MÜnich, Germany told me years ago already: BMW macht fÜr fahren nicht zu laden.....(loosely translated, BMW's are made to be driven not load them like a truck....At the time he was maybe a bit ahead of his time but not anymore with the post 2004 BMW's .

 

car is 2008 550i 6-spd (LCI)


yeah when i was typing out the time i drive in that post, i thought 10min's to work, 10 min's home, could very well be the issue.

 

Might be on original battery..

Regardless, mine did pretty similar things when the battery was going. I had sat out in it a few times trying to learn the whole "coding" thing and apparently ran it down pretty well. New battery fixed it