[masterh]

I know I should do the battery registration but I haven't done it yet. The battery dies after couple weeks. Now I have to jump it after not driving the car for 2 days.

I read someone talking about battery died after 1 year without battery registration. I just figured I could swap it out since it comes with 3 year guarantee.

Anyways, I don't know history about this car. When I bought it a month ago, it had cheap recycled battery so I just figured it had a bad battery.

I am not sure it died because I didn't register it or it might have some parasite drain somewhere (no audio mods or anything)

Maybe the car kept charging the battery when it was full and caused to go bad?

Should I register it now and see how it goes or Replace with new one and register asap?

[ctuna]

This is not the sub forum for battery questions which have
been quite hashed out .
1) If you don't drive the car enough the battery won't get charged.
2)If you switched battery types from lead acid to AGM or vice versa
it can cause problems if you don't reprogram the car for battery type
and size.
3) Did you match the amp hour size.
4)You could have a parasitic drain.
5) The alternator could be going bad.

http://www.bimmerfest.com/forums/sho...15&postcount=6

[techwhiz]

Originally Posted by masterh

I know I should do the battery registration but I haven't done it yet. The battery dies after couple weeks. Now I have to jump it after not driving the car for 2 days.

I read someone talking about battery died after 1 year without battery registration. I just figured I could swap it out since it comes with 3 year guarantee.

Anyways, I don't know history about this car. When I bought it a month ago, it had cheap recycled battery so I just figured it had a bad battery.

I am not sure it died because I didn't register it or it might have some parasite drain somewhere (no audio mods or anything)

Maybe the car kept charging the battery when it was full and caused to go bad?

Should I register it now and see how it goes or Replace with new one and register asap?

My guess is a bad regulator and the battery is under/over charged.
Regulator can be changed with the alternator on the car.

[masterh]

I doubt the Alternator is going bad. The battery was completely dead. I coudn't even unlock the door with a key fob. I drove around little bit, turned it off and it started normal which means Alternator charged the battery?

thanks for pointing out AGM battery. Maybe the car with AGM from the factory and it hasn't been coded yet.

Originally Posted by ctuna

This is not the sub forum for battery questions which have
been quite hashed out .
1) If you don't drive the car enough the battery won't get charged.
2)If you switched battery types from lead acid to AGM or vice versa
it can cause problems if you don't reprogram the car for battery type
and size.
3) Did you match the amp hour size.
4)You could have a parasitic drain.
5) The alternator could be going bad.

http://www.bimmerfest.com/forums/sho...15&postcount=6