[VP Electricity]

I've seen a lot of confusing information posted about battery replacement, registration, and what it means. I recently had a conversation with a very helpful BMW tech about this, and here's what I learned:

There are two kinds of batteries BMW uses - standard and AGM (Advanced Glass Mat, like Optima, Odyssey, and Kinetic).

The white ones are standard, the black ones are AGM.

Each type of battery has a "charging map" that BMW has created from research. This changes the characteristics of the alternator's output depending on how long the battery has been in the vehicle. This "timer" is what starts when you register the new battery. There are also different maps for batteries of different amp/hour capacities.

HOWEVER:

The car can only hold one "map" at a time. If you have a standard battery (which my car came with) and you upgrade to an AGM battery (which is what I did), then the registration process is NOT sufficient. Your car doesn't have the right map to use for an AGM battery!

You need to recode the car to tell it that you have a AGM battery, so that you can download the new charging map into it, and THEN it knows what to do.

This is also true if your car came with a black AGM battery, and you have downgraded to a standard type battery. You now need to get the car coded for the new battery.

Even if you change from one battery to another of the same type, if one has more amp/hour capacity than the other, then recoding is needed. The maps are also different for batteries with different amp/hour ratings.

An Autologic shop can do this far easier than the dealer, I'm told.

I hope that clarifies what is being talked about on this matter.

[jjmanda]

Very good explanation.

Thanks!

[fdriller9]

I thought it was absorbent glass mat?

Anyway here's more info. I wrote this after getting my braille retrofitted.

http://www.e90post.com/forums/showthread.php?t=473109

An autologic shop will be cheaper if the tech knows how to do it. I took it too a shop with an autologic but he had no idea how to retrofit the braille into my. He spent about 3 hours trying to figure it out, call people, etc.

[B-737]

Thank you for posting this Ken

[ctuna]

http://www.e90post.com/forums/showth...y+registration

I wonder if the technique is solid ?
They seem to be able to both register and select new profile maps.

[redz06]

Well, I didn't drink the Koolaid. While this is my first BMW, I have owned many performance cars before. Two Porsches, Two Corvette Z06s, one of which I still own. Both Z06s had AGM batteries. I have owned Red Top (AGM) batteries in other cars before (and am not impressed). So I fail to understand why I should be playing money to teach my cars how to "shake hands" with replacement batteries. Never done it before -- not planning to do it in 2014 or so when my BMW needs a replacement.

[VP Electricity]

Do what you want, but you don't need to make disparaging remarks about me. Good job looking like a cranky old man, though.

[Technic]

Originally Posted by redz06

Well, I didn't drink the Koolaid. While this is my first BMW, I have owned many performance cars before. Two Porsches, Two Corvette Z06s, one of which I still own. Both Z06s had AGM batteries. I have owned Red Top (AGM) batteries in other cars before (and am not impressed). So I fail to understand why I should be playing money to teach my cars how to "shake hands" with replacement batteries. Never done it before -- not planning to do it in 2014 or so when my BMW needs a replacement.

The only thing in common among all the cars that you mentioned is that they use AGM batteries. Their particular AGM charging algorithm , their electrical system or the actual battery itself are not necesarily the same.

So I failing to see your contribution to this thread.

[ZZZZ]

Originally Posted by redz06

Well, I didn't drink the Koolaid. While this is my first BMW, I have owned many performance cars before. Two Porsches, Two Corvette Z06s, one of which I still own. Both Z06s had AGM batteries. I have owned Red Top (AGM) batteries in other cars before (and am not impressed). So I fail to understand why I should be playing money to teach my cars how to "shake hands" with replacement batteries. Never done it before -- not planning to do it in 2014 or so when my BMW needs a replacement.

Not a problem. Be sure not to re-register your battery again in 2015 when your battery needs replacing again after it dies prematurely.

You are not teaching the car to 'shake hands' with the replacement. You're telling the car that there is a new battery in the compartment and the capacity of the battery. This is important if you change the capacity of the battery from the stock mAh.

Your car is always monitoring the battery, and uses this information programmed into it to correctly gauge how much juice is left. If the battery is getting low the car slowly shuts downs systems to conserve energy. It also does this for the 'rest' feature in the climate control. The computer always tries to leave enough juice in the battery for the engine to start. The computer can't calculate this properly if your battery is 70mAh but it thinks the battery in there is 90mAh for example.

But, it's up to you. There are guys on here who don't think doing oil changes before the BMW recommended oil change interval makes a difference either.

[redz06]

My 2001 Corvette Z06 was built new with an AGM battery. After less than 3 years, it died and I replaced it with a Red Top, also an AGM. In two years the Red Top Would not hold a charge for even a week. So I replaced it with another Red Top. Within a year it would not hold a charge for a week. So I said audios AGM and put in a lead acid battery. After more than 4 years the lead acid battery is still going strong. Go figure.

My 2008 Z06 has another AGM battery in it, and I am hoping for a longer run. I generally get 4+ years in my climate. and I do change my oil (fully synthetic) and filter quite regularly thank you very much. I will be halving the BMW recommendations for oil change intervals.

Originally Posted by ZZZZ

Not a problem. Be sure not to re-register your battery again in 2015 when your battery needs replacing again after it dies prematurely.

You are not teaching the car to 'shake hands' with the replacement. You're telling the car that there is a new battery in the compartment and the capacity of the battery. This is important if you change the capacity of the battery from the stock mAh.

Your car is always monitoring the battery, and uses this information programmed into it to correctly gauge how much juice is left. If the battery is getting low the car slowly shuts downs systems to conserve energy. It also does this for the 'rest' feature in the climate control. The computer always tries to leave enough juice in the battery for the engine to start. The computer can't calculate this properly if your battery is 70mAh but it thinks the battery in there is 90mAh for example.

But, it's up to you. There are guys on here who don't think doing oil changes before the BMW recommended oil change interval makes a difference either.

[rogerdiaz]

autozone thinks my car has an AGM. So it wants me to buy a H6.

Indy wants $400 for a new battery.

There must be a better way. Appreciate any input.

[ctuna]

The white batterys are lead I think they even have
the Pb (lead)symbol on them. I used a Interstate Mtp 49/h8
which actualy exceeds the amp hour rating. Its been in
there three years. You need at least an H7
Do not let anybody use battery back up on the car when
changing batterys it blows the OBD/Instrument cluster fuse
and does not back up anything anyway.
Do not close the trunk with the battery out.(electric trunk lock)
As long as you get a lead battery with equivalent form(49/h8)
factor and amp hour rating you can buy a battery anywhere.
Some people get them at walmart.
don't let autozone or any place like that change the battery
you are risking the car if you do.
And you need to find another Indy it should be at least
100 dollars cheaper at an Indy. I can't see how they would
be charging dealer prices for this service that takes them no
more than a half hour at most.

Most of the threads on this are on the general and coding subforms by the way.

Registration
!)Buy the Carly app and do it yourself and have diagnostic
and coding ability for something like 110.
2)Buy a coding cable and invest a bunch of time in downloading and setting up coding software.
3 )Pay no more than 50 bucks at and Indy to register
the battery.
4)Find a coder in your area the will do it maybe for free

It takes no more than 10 minutes to do this most of which
is plugging in the cable and finding the menu in the software.

http://e89.zpost.com/forums/attachme...1&d=1368060381

[rogerdiaz]

Originally Posted by ctuna

The white batterys are lead I think they even have
the Pb (lead)symbol on them. I used a Interstate Mtp 49/h8
which actualy exceeds the amp hour rating. Its been in
there three years. You need at least an H7
Do not let anybody use battery back up on the car when
changing batterys it blows the OBD/Instrument cluster fuse
and does not back up anything anyway.
Do not close the trunk with the battery out.(electric trunk lock)
As long as you get a lead battery with equivalent form(49/h8)
factor and amp hour rating you can buy a battery anywhere.
Some people get them at walmart.
don't let autozone or any place like that change the battery
you are risking the car if you do.
And you need to find another Indy it should be at least
100 dollars cheaper at an Indy. I can't see how they would
be charging dealer prices for this service that takes them no
more than a half hour at most.

Most of the threads on this are on the general and coding subforms by the way.

Registration
!)Buy the Carly app and do it yourself and have diagnostic
and coding ability for something like 110.
2)Buy a coding cable and invest a bunch of time in downloading and setting up coding software.
3 )Pay no more than 50 bucks at and Indy to register
the battery.
4)Find a coder in your area the will do it maybe for free

It takes no more than 10 minutes to do this most of which
is plugging in the cable and finding the menu in the software.

http://e89.zpost.com/forums/attachme...1&d=1368060381

Excellent. Other member helped me find the lead acid group 49 H8. Gonna buy carly. Thanks. Post should be a sticky.

[cdgatti]

If your getting the Carly you can re-code and register it to an AGM type. I would recommend changing to AGM, they are great. Not much more money.