korrosive

Correct on the OEM spec battery. You will not need to program it to get it to work. There is debate however on whether it should be programmed at all, but as Achtung suggested, just get the battery in there and get your car going again and then you can decide for yourself if the programming is worth it. I also think you should jump the car before just dropping a new battery in there. Because if your alternator is out, your new battery will be gone in no time.

AchtungE60

You do not NEED to register the battery. It is suggested but not required. Like I said if you want to swap it out an H8 is perfect. I personally have been running the EverMaxx H8 over the OE battery. I just like to put in new batteries every three years just because. Battery I run. I got it for $79 i think it's about $99 now. I just swapped one in a 08 328i and in that car i noticed that the IBS did not give power to the engine when not plugged in. I plugged it in, registered and reset and it was fine. I assume if i deleted the IBS from the VO and encoded all modules I wouldn't have had any issue.

http://www.google.com/imgres?hl=en&b...1t:429,r:0,s:0

OTSe60

Thanks Korrosive, Achtunge60 for the clarification and everyone else who replied. You guys have all been very helpful so far! I will do the jumpstart and see what happens today.

Kaizen

Yep, my bet is also on the battery. Before you buy a new one though, take it to the dealer to charge it. They have top notch battery chargers and they can also diagnose if you need a new battery or not. My dealer does it for free, but it might not be worth it if they charge you.

About 4 months ago I was in a similar situation, though I had to jumpstart my car every 3-5 days. It would not hold a charge. So i took it in to get charged and it lasted about 3 months or so until it happened again. I finally gave in and bought a replacement battery with programming from an indy for about $230.