Bimmerpost for iPhone and Android have just been updated with a host of bug fixes. If you've ever had trouble logging into it in the past, give it a try now!
BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read

Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Coding / ConnectedDrive / Audio-Video / Electronics / Bluetooth / I-Drive & Nav
Post Reply
Thread Tools Search this Thread
      05-07-2016, 11:49 PM   #1
Apex Everything
Apex Everything's Avatar

Drives: M3
Join Date: Nov 2015
Location: A place

iTrader: (3)

Battery Woes

How can I tell it is truly time to replace my battery?

I have an interesting chain of events which would probably de-charge any cars battery, so I am having trouble determining if I should pull the trigger on a new battery.

End of March, I let my car sit for 4-5 days no charger (before I received one) because of a nail in the tire. My position allows me to work from home 2-3 days a week or for emergencies (car issues, snow etc.) so letting the car sit had no effect on my life.

When I drove the car to the tire place to install my new tires I received the dashboard alert for battery drain. I got my tires done and then borrowed my father in laws charger and let it charge overnight. Since then never had a dashboard alert for battery drain.

The first 3 weeks of April my car was at BMW to have engine warranty work done. During that time I can imagine it was not driven or started up often. Even after the work was completed. So 3 weeks of my M3 battery draining with little to now charge build up from my driving.

Again, since the one time I had the battery alert I have had no dashboard messages.

I obtained a Optima 400 battery charger, this charger analyzes your battery and tells you its charge level from 0-100%. When I hooked it up to the M3, it read as 25%.

I am worried, but the car sat for half a month, so I am thinking it just needs some constant recharge.

Some more background, I bought the car used and it is a 2012. I can only assume it is the first battery in the car.

My battery knowledge is lacking so I am thankful for any insight or opinion.

If it goes south, I am thinking about getting a Brallie 21 battery, can you also suggest any performance battery options in the $200-300 range? I do not want to put just any consumer level battery in a M3, #BecauseM3

Your thoughts......?
Appreciate 0
Post Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -4. The time now is 04:16 PM.

Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.,,,,,,,,, logo and trademark are properties of BIMMERPOST