DIY battery replacement e90

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nj325ci
Posts: 162
Joined: Wed May 21, 2008 9:38 am

DIY battery replacement e90

Post by nj325ci »

I can't believe I'm actually asking such a basic question but is it true that you can't just replace a battery in recent model BMWs without having to do a reset procedure requiring the proper scan tool? What procedure does the dealer follow that can't be replicated at home? I'm not trying to take short cuts but my car has enough juice to power lights etc but not turn over and it would be less of a hassle to pick the new battery up and do the swap in my driveway than to charge the current battery and bring the car to the dealer.

Thanks, Bill

afadeev
Posts: 277
Joined: Mon Sep 28, 2009 9:02 pm

Re: DIY battery replacement e90

Post by afadeev »

nj325ci wrote:I can't believe I'm actually asking such a basic question but is it true that you can't just replace a battery in recent model BMWs without having to do a reset procedure requiring the proper scan tool? What procedure does the dealer follow that can't be replicated at home? I'm not trying to take short cuts but my car has enough juice to power lights etc but not turn over and it would be less of a hassle to pick the new battery up and do the swap in my driveway than to charge the current battery and bring the car to the dealer.

Thanks, Bill
Bill,
Modern BMWs and MINIs have added adjustable charging algorithms to the alternator software. In theory, if your old battery was extremely weak for a long time, the alternator could have been set to charge at an aggressive rate to keep it going. And if you put in a new battery without resetting alternator software settings, it may attempt to over-charge it.
http://atlanticmotorcar.com/tech-tip-bm ... acement-2/

Done competently, "battery registration" takes 5 minutes.
If you take it to a dealer, they will charge you for at least 1 hour of labor, bringing the total to $400+ (including over-priced OEM battery).

In real world, most people I know who DIY their cars just throw in a new Autozone / PepBoys / DieHard / etc / battery of equal or higher rating, and report zero problems.
Just make sure it's the same lead-acid (or AGM) battery that came out.

YMMV,
All generic disclaimers apply.
Do not eat, lick, or swallow. Not a toy.
Do not remove this disclaimer under penalty of law.
https://sites.google.com/site/beecherbo ... isclaimers

a

BJerolimic
Posts: 740
Joined: Wed Sep 15, 2004 2:24 pm
Location: Montville, NJ . . . . . . '98 M3 - '01 M5 - '08 X5

Re: DIY battery replacement e90

Post by BJerolimic »

Bill if you get the right battery (correct amp hours, not just the same group type battery) I can register the new battery with my Carly adapter and BMWhat app. I purchased both as I had to swap in new battery on my wife's "new" e70 X5
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and gone but not forgotten:
'00 323Ci Steel Grey / Black Dinan & UUC & Schnitzer mods
'89 325iX Diamond Black / Black 4dr 5spd Dinan chip, Ireland exhaust, H&R+Koni
'01 525iTa

nj325ci
Posts: 162
Joined: Wed May 21, 2008 9:38 am

Re: DIY battery replacement e90

Post by nj325ci »

Thanks very much, I'll defintely PM you when I get the battery. It's holding a charge from day to day so I can get the battery and work around your schedule. Since I last saw you my work location has moved to Morris County so I can easily catch up with you.

And BTW congratulations on the additions to your growing family, your daughter and your e70!!! (saw that in another post)

Thanks again, Bill

BJerolimic
Posts: 740
Joined: Wed Sep 15, 2004 2:24 pm
Location: Montville, NJ . . . . . . '98 M3 - '01 M5 - '08 X5

Re: DIY battery replacement e90

Post by BJerolimic »

thanks!


btw I found the best deal was at Batteries Plus in Whippany, at least for my e70 (may be different battery than your e90 and again you need to find the right or closest AH battery to what is currently in the car), more details on batteries for newer BMWs and some price shopping + warranty comparison:

http://www.xoutpost.com/1057230-post67.html
Image

and gone but not forgotten:
'00 323Ci Steel Grey / Black Dinan & UUC & Schnitzer mods
'89 325iX Diamond Black / Black 4dr 5spd Dinan chip, Ireland exhaust, H&R+Koni
'01 525iTa

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