[dixy2k]

Originally Posted by Hoooper

Is there a point where the car tells you the battery needs to be replaced or are we just relying on noticing that its dead? I can tell mine is going to need to be replaced soon, slow cranking even when its fairly warm out, cant sit in the car with the radio on for long at all, and the battery voltage is maxing out at 12.18 which is like 25% charge at best. Im kind of holding out at this point to see how long it goes but I doubt it will be too much longer

For about a week my car tells my the battery is low.



What is AGM?


Trying to figure out which battery I need. Group 49 or 94?

[Hoooper]

AGM - absorbed glass mat, it doesn't have battery acid and lead plates like a normal battery. If your OEM battery is white its normal lead acid type. The AGM ones are black.

[BB_cuda]

Originally Posted by dixy2k

For about a week my car tells my the battery is low.



What is AGM?


Trying to figure out which battery I need. Group 49 or 94?

My battery specs for OEM battery were size 94 or euro equivalent H7. the problem is in aftermarket, you can't find a 94 that delivers the required electrical specs of RC=160 minutes and 90 Amp-hours. It is hard to find the Amp-hr spec on batteries. This is why I went to the manufacturer web sites that make for Walmart, Orielly, Sears, Autozone, etc.

What I found was to go with the larger group 49 or euro equiv H8. Dealer replacement for me was a larger group 49. It is white but is lead acid. I know is is lead acid as it has the vent connected on the forward end. Per earlier post, it has the circular caps with "+" signs embossed in them, like the Deka/East Penn manaufacturer. If you go look at the group 49/H8 at Orielly, it is its twin except the Orielly one is black. I recall, the AGM doesn't have the vent hook up.

I have no affiliation with O'reilly, just like their product. NAPA appears to sell same Deka made battery.

Advance Auto parts has H8 AGM size made by Johnson controls. This one has 95 amp-hr and 170 RC. It looks like it would be near top of my list as well. Good luck and go look at the sheets I posted above. I have an excel sheet with some of this organized but we can't post excel files here (why is that moderator?).

[taibanl]

Originally Posted by BB_cuda

My battery looks like the deka group 49 but it is white. deka and exide spec sheets attached. Sorry, the exide one is only for AGM. I had it changed January 2014. When did they go to off the shelf Exide?

Apparently July 2012. See attached: SI B61 22 12 92AH Exide AGM battery local source.pdf

[BB_cuda]

What i take away from this is BMW doesn't carry an AGM part anymore and sources the Exide as you say. Perhaps they still stock the lead acid one in an OEM. My battery says BMW on it and was put in service January 2014. Aftermarket discussion above. The exide is 92 amp-hr so it has good capacity.

Here is the Exide specs for AGM. See page 4 , 2nd row from bottom. This looks very close to the battery you speak of vice 90 amp-hr instead of 92 which is quoted in the SIB you attached. Spec sheet looks like Exide has a very good product compared to standard AGM. It doesn't degrade in amp-hrs like a lead acid does (see page 3). Looks like I will go AGM when the OEM group 49 replacement dies ~3 years, I'm guessing. Depends on the battery tender keeping this one up. I didn't use battery tender until near the end of original one's life.

After seeing the Exide AGM sheet, the aftermarket Advance Auto might be worth another look although it is Johnson Controls made (not Exide).

[TDIwyse]

This is all interesting stuff. So far my 4 year old original battery is holding up well, but I'm not expecting many more winters from it.

Do any of you guys know the weight difference between the AGM vs lead acid batteries?

Anyone know if the BMWhat battery registration is capable to change battery types if one switches from what was originally in the car?

[BB_cuda]

Originally Posted by TDIwyse

This is all interesting stuff. So far my 4 year old original battery is holding up well, but I'm not expecting many more winters from it.

Do any of you guys know the weight difference between the AGM vs lead acid batteries?

Anyone know if the BMWhat battery registration is capable to change battery types if one switches from what was originally in the car?

Go back to post #19 where there is a deka spec sheet. There is a weight column in the middle. AGM/group 49 weighs 58.5 lb. Lead acid/group 49 weighs 54.5 lb.

Unsure about BMWhat registration. I would take a look at your Bav Technique cable, it might be able to do the job. Changing type is a little trickier than just doing a same for same register.

[TDIwyse]

Originally Posted by BB_cuda

Go back to post #19 where there is a deka spec sheet. There is a weight column in the middle. AGM/group 49 weighs 58.5 lb. Lead acid/group 49 weighs 54.5 lb.

Thanks. I missed the footnote that explained the AGM vs Lead acid. I had been under the impression that the AGM would weight less but it appears not to be the case.

[Hoooper]

Originally Posted by TDIwyse

Thanks. I missed the footnote that explained the AGM vs Lead acid. I had been under the impression that the AGM would weight less but it appears not to be the case.

deka might be building a cheap(er) AGM battery. Its not as well rated for capacity, and its heavier. That doesnt make sense in a 1:1 quality comparison of flooded cell and AGM

[dixy2k]

I called two local dealers, they both quoted me the same price, $248.85.
Walmart sells the Everstart battery 94r group for $149.99.

Doing some reading today and apparently the bigger issue with the battery is the registration. So far I haven't been able to find a DIY for it. The physical replacement is easy. I need to talk to the dealer again to find out if they are willing to register the battery in the event I did not purchase it from them, non OEM, etc.

[Hoooper]

I'm going to plug in a maintainer/desulfater I have and see if that gets me anywhere. Might as well see if it helps before I go blow $200 on a battery.

[dixy2k]

Hooper, on page one a member stated the 335d does not have the IBS (intelligent battery sensor). Is this true?
In this case we don't have to worry about registering the battery?



Here's a link for a possible DIY

http://www.e90post.com/forums/showthread.php?t=532315

[dixy2k]

One more thought

If the battery is disconnected for a period of time, wouldn't the ECU reset the battery issue too?
I know people do it for different purposes (TCU and shifting issues for example).

[BB_cuda]

Originally Posted by dixy2k

I called two local dealers, they both quoted me the same price, $248.85.
Walmart sells the Everstart battery 94r group for $149.99.

Doing some reading today and apparently the bigger issue with the battery is the registration. So far I haven't been able to find a DIY for it. The physical replacement is easy. I need to talk to the dealer again to find out if they are willing to register the battery in the event I did not purchase it from them, non OEM, etc.

When i was shopping for a new battery, I asked a local indy if he would do the register only right after I put new one in. He said yes for $50 if he didn't have to touch the battery. Something to be conscious of is if you change types, the computer needs to know this. Some of the things that can register a battery can only do it if type stays same, other ones can change type and then register. Seems i recall a really good thread on this over on the 'fest. I forget whether the Bavarian technique cable can do both or only the register of the same type as previous.

[Frediesel]

Just purchased the inApp from BMWhat and it looks like it lets you register both the same or different type of battery. Haven't tried it yet, but it's nice to know it's there when I need it.

[Hoooper]

Originally Posted by dixy2k

Hooper, on page one a member stated the 335d does not have the IBS (intelligent battery sensor). Is this true?
In this case we don't have to worry about registering the battery?



Here's a link for a possible DIY

http://www.e90post.com/forums/showthread.php?t=532315

I have no idea. Realoem shows an IBS but also lists a bunch of things which would cause you to have the IBS or not. It's kind of confusing on there, but based on what I think it says, every 335d would have it because we have auxiliary heating. Either way I have it because I have nav (one of the several things on the list)

[dixy2k]

Originally Posted by Frediesel

Just purchased the inApp from BMWhat and it looks like it lets you register both the same or different type of battery. Haven't tried it yet, but it's nice to know it's there when I need it.

Does this app work with the bluetooth adaptor?

[Frediesel]

Originally Posted by dixy2k

Does this app work with the bluetooth adaptor?

Yes, I purchased the adapter through BMWhat (iViNi-app) using PayPal.

[austinla335d]

Just had my battery done at offset in SoCal, under $200 changed and coded.

I'm in a low mileage 2011, so it depends on a number of factors. 4-6 years is typical.

[natefank]

I think mines on its way out, I keep getting a excess battery discharge warning. I have CPO and the maintenance package for another 25k miles, so hopefully they will cover it

[dixy2k]

Originally Posted by austinla335d

Just had my battery done at offset in SoCal, under $200 changed and coded.

I'm in a low mileage 2011, so it depends on a number of factors. 4-6 years is typical.

Where's that place?

Walmart battery plus app would be just about the same as you paid.
I checked with Pep Boys yesterday and it comes out to $364 including taxes.

[austinla335d]

Originally Posted by dixy2k

Where's that place?

Walmart battery plus app would be just about the same as you paid.
I checked with Pep Boys yesterday and it comes out to $364 including taxes.

It's in Glendora. I'm sure you used google if you really needed to know.