Quite a few guides show how to disconnect the negative terminal of the battery but I needed to replace the battery in my 330i and I couldn't find any guides that explained how to remove it so here we are.

I understand that for many people this procedure will be self explanatory but...

i just called a german auto place by me and they said to reporagm the battery would take 3 hours and cost 270 in addition to the price of the battery.

Good God. My indie did in about 10 mins flat, and charged $37. When I expressed a little surprise at the price, they said clearing other codes that a flat battery can cause can take a while - fair enough. But probably wasn't the case in how quickly they did mine.

I bought a Bosch Group 49 battery which is infamous for either going flat in 2 wks, or in one case that I read, exploding (from overcharging) without registering it as a new battery.

Beware of Bosch batteries, the first one I got at Pep boys had one cell's level below the plates, the second they gave me, the top was not sealed to the body correctly, and it leaked acid over my hands and the wiring when I was installing it. The third one is in and working, higher CCA does mean nice quick starts, but not worth the hassle.

And double check that the end plate fastener is installed correctly, I had it reversed, and while it all looked right, the battery could move side to side and up and down a bit (at the back.)

Thanks for the write up with pics! This car is starting to piss me off! I just replaced my battery today since my old one wasn't holding a charge. Called the dealer to try schedule in a new one, the service guy asked if they wanted them to change it, so I said if I can change myself, then I'd do it. He said no problem, transferred me to parts. So I jump my car an go down, the parts guy asked how much amps the battery is, he says if you replace with the same amount as old battery YOU DON'T HAVE TO REPROGAM THE CAR. Only if you get a different amperage battery. Ok, no problem($280 for mine), took it out to the parking lot and changed it( was the hardest battery fricken change ever!). While reinstalling it, I couldn't figure out where that one damn wire went to, so look on here and looks like it's an accessory wire? Others have found the same, so I guess it's all good. Car started right up, had the massive warning lights on, but when driving away, they all went off and all is fine. Sorry for the long rant, just to summarize:

If you replace battery with same cranking amps then you DONT have to program!
Car is a bitch!
There is one extra cable that isn't connected to anything. I hope.

ok bear with me please.
I have looked at whats in the car now and found it to say
70Ah 570A
120RC 570CCA

I think this is fairly common for the 325i

At AutoZone and Sears I've asked about batteries on the car and both seemed baffled and offered several batteries not knowing which I "needed". None of what either offered were 570A/CCA. The offered much more. (this is the bear with me part) I know very little about batteries so can I/should I get a higher "rated?" battery? Or anyone who had that battery wanna just tell me what to get?

anyone?

based on my experience of buying and installing an aftermarket battery (see above), if I had to do it over, I'd go to the dealer and buy the OEM battery.

why's that? you seem to be the first i've read of to wish they'd gone to the dealer

Just did it with the BMW battery it only cost me $181 + tax, worth the extra $ to get the right part. Not as easy as on a regular vehicle but done. Adapatation reset with BT Tool.

When reinstalling, I installed the foam piece first, I couldn't get it in afterwards. The battery weights as much as a skinny teenager, damn!

I also had a spare wire, thanks for explaining what it was for.

Great write-up. Replaced the battery tonight with an Autocraft, size 48h6 which is slightly smaller than the 49. I squeezed a piece of wood between the battery and foam piece for a tight fit. Gotta love the members of this forum for saving everyone $$$ with detailed DIYs instructions.

Great DIY. Do you need to turn your headlights on before connecting the negative terminal, as originally suggested?

I have an E92, 2007, 9/06 build...

I took a pic of my battery part number if anyone wanted it...

Funny... looking at the "magic eye" I cant tell if it is green or black... should it be obvious?

~Frost

Pic one: is this "green" ? LOL

You have to view the diagnostic window directly above it. I even brought trouble light close to it as it is quite dark on that side of the trunk. We have exactly the same battery part #. I have Sept 05 build with 57K miles, auto with sport package and still on my original battery

Is their a manufactured date on the battery? Trying to see if my battery is original. Wishful thinking, but maybe previous owner replaced it with OEM.

christofor, click this link from motor magazine http://www.motor.com/article.asp?article_ID=1479
fourth paragraph from the bottom describes how to tell if you have the original battery.

Wow, thx!!! Mine is original, top of negative post was stamped with "23 05". That means my battery was manufactured the 23rd week of 2005. Thanks again.

Roundel magazine, February 2011, page 99:

Great DYI. I used it to get a wrench that fell behind the battery - when I was disconnecting the negative terminal. (You can see the wrench in the photo attached, lol.)

I have a 330 XI and have the same specs on the side as the picture above: 12V 90Ah 720 A.

For info I measure the battery's size:
LONG LENGTH: 13 + 7/8 (approximately 14)
WIDTH: 6 + 5/8
TALL: 6 + 5/8

Have not replaced the battery with a different brand, but will try myself when it starts die-ing.

Hey does, anyone know what this wire connects to? (I bumped up against it a few times. Looks like it held up okay, but is awfully close to the battery)

Attached Images

 

Here is a picture of the connector that connects to a terminal - for the amateurs like me that have no idea what it looks like and is scared of which way to pull the wires.

The nut and bolt tightens an end of the connection to cause the "O" to tighten. Pulling vertical upward after completely unscrewing the nut will allow a disconnection.

Where does the vent tube go? Pepboys installed my battery with the vent tube hanging from the battery. Any pictures will greatly be appreciated. THANKS!

Pepboys

It wasnt on my list of places to go either, but you gotta do what you gotta do when you're stranded with a dead battery. Does anyone know where the hose connects on the car side?

^take a look at the 10th pic in Op's post. You can see the tube that goes into a black elbow on the positive side of the battery. The reason why they left it hanging is probably the battery they installed has the vent located in the center of the battery and couldn't reach. Take it back and tell them to hook up the vent hose. It is not there for show.