2008 550i
For the past three years when the temperature goes below 40 F I will randomly get a "high battery discharge" message (no comfort access). I have taken it in to the dealer and they can't replicate the problem and show the battery is good. I have no issues during the summer. I was hoping by now which ever one of the 60+ modules in the car was causing the issue would just die, but no luck. Can anyone give me a way to trouble shoot it?

Thanks

 

have they kept the car over night to try and replicate the problem?

 

is your battery original? if so, its probably past its time.
check the negative battery post. date should be stamped on top of it, if its original.

 

The Battery was new in 2010. I guess I need to take it back when it is cold and let them keep it overnight. The hidden menu shows 14 volts when driving. If i turn everything on (I mean everything) it drops to 13.2 volts.

 

Hello i had the same problem what fix mine work charge battery up with a 2amp charger 24 hrs then lock each nignt with fob and take fob at least 10 or 15 foot from car this is crazy i know but it work and thats a bmw for you but people like us like them and will do stuiped stuff to drive them

 

Even if its 2 years old it should not do that. E36 with 15 years old original battery does not do that with temperatures below -30c. I have this problem too with my e60 and happens randomly (most days no problem). Probably some grounding problem. Could be found by electrical meter (youtube).

 

To the OP, i'm experiencing that exact same problem. It's been fairly cold by northern california standards the past week (temps in the 30's ) and I've had this error pop up 3 times in the last two weeks. The car otherwise starts up just fine and drives the same.

In searching "High Batter Discharge" the most common answer is ensuring your keyfob is not near the car so that the car can fully go into sleep mode and not keep being "woken" up by the key fob being close. I'm going to move where I keep my keys, tonight and see if that helps in the morning. If it doesn't, then I'll look into a new battery.

 

Interesting I'm guessing you have comfort access? I used to leave my key fob on top of my roof inside my garage and I never had this issue. I don't have comfort access, so this would only apply for people with that option. If it does turn out to be this, hopefully you can have bmw fix the issue through warranty.

 

I don't have CA. I use a battery charger occasionally to help with the issues. I have never had to jump start the car.

 

that has to be a record for battery age