So recently I ran into an issue, I got into my car a few days after new year’s eve and the clock had been reset with the little dashes requiring me to input the time. At first i thought it was a little quirk maybe bmw had you reset the time and date after a new year. But then i realized almost everytime i got into the car i’d have to reset it. It had been brutally cold for where I live (florida). After i reset it the first time, the yellow car on lift symbol popped up. I thought it was because i had a service scheduled for january 2018. The car started pretty long on the coldest day it’s seen with me, sounded like a diesel starting in -10F lol. Other than that the crank has been a tiny bit long but starts right up and idles fine. I get no battery indicators when driving but as soon as I stop at my destination and try to listen to the rest of my song the yellow battery light pops up and i leave it. But i come back after a few hours and it starts right up. Today I decided to buy a cheapo battery charger from wally word and it was actually pretty decent. I let it charge for a couple hours till it said it was charged/maintaining. Then I started it, took the same amount of time, clock was present. No warnings, no yellow lift. Went for a drive around the neighborhood just to see if so could use the rest air, as before i couldn’t and i read when your battery is fubar’d rest air won’t work. when I came home turned the car off and few seconds later bam yellow battery. In the hiden menu car off it sits at 12 flat and idle its 15 flat. The cheapo battery charger had a light for bad battery which wasn’t lit but not sure how much i’d really trust that.