Important Battery replacement info

[JCtx]

Originally Posted by Technic

After registration the error disappeared.

Is your DieHard a wet cell, like stock? I refuse to believe that swapping identical batteries (be it OEM or whatever, both wet cell with the same amp/hr rating) requires any coding. If it does, I'm glad as hell this is my first and last BMW. And before I pay anything to a dealer for such stupidity, I'd trade the freaking car (which I'll eventually do anyway) in and call it a day. Yes, I rather pay thousands more than getting unfairly raped even for $100. It's ridiculous.

By the way, a $20 Battery Tender Plus knows which battery it's hooked up to, and charges it accordingly. It's a ripoff to make owners go to a damn dealer for doing something as mundane as replacing a dead battery. I charge mine every week, so it's unlikely I'll ever have to replace it before getting rid of the car.

[BimmerM]

My car came with a 90ah 900cca AGM battery made by Banner.

So the question still remains, will charging the battery in the E9x cause any issues with the algorithm that is stored in memory?

I have been using a trickle charger for years and it would suck if I can't do the same for this car if it messes up the algorithm.

[ChrisK]

Originally Posted by quality_sound

There is no way you have to "tell the car you're putting in a new battery". None. It defies basic electronics. If you had to reprogram the car for a new battery you'd have to do the same thing any time you disconnected the battery and I've disconnected and removed mine a number of times. What? There's some malicious code in the ECU that tells it that OEM electrons are different than non-OEM electrons and in that case blow the battery up? Give me a fucking break.

Typical M owner superiority complex. It's a car, not rocket science.

My buddies Audi Q7 required an ECU update after the battery was changed.

[gr8000]

wow, pretty serious stuff... battery blowing up as a result of not registering it in the ECU?

This makes me think (among others) that the alternator varies its output from low to quite high current depending on paramenters such as the battery state (full / empty & condition) and the driving conditions (eg no charging when at WOT i.e. when max engine power is needed on the wheels and up to max charging at all other times).

Impressive... It just remains to be seen for how long will all these electronic gismos last!

On a different note, does anyone know (or can make an educated guess on) what might me the operating life of the OEM battery?

[Technic]

Originally Posted by elp_jc

Is your DieHard a wet cell, like stock? I refuse to believe that swapping identical batteries (be it OEM or whatever, both wet cell with the same amp/hr rating) requires any coding. If it does, I'm glad as hell this is my first and last BMW. And before I pay anything to a dealer for such stupidity, I'd trade the freaking car (which I'll eventually do anyway) in and call it a day. Yes, I rather pay thousands more than getting unfairly raped even for $100. It's ridiculous.

By the way, a $20 Battery Tender Plus knows which battery it's hooked up to, and charges it accordingly. It's a ripoff to make owners go to a damn dealer for doing something as mundane as replacing a dead battery. I charge mine every week, so it's unlikely I'll ever have to replace it before getting rid of the car.

Yes, it is.

Peronally, I don't think that this is as big as an issue as discussed in that particular thread. It could be possible that the battery "explosion" reported in that thread was caused by something unrelated to battery registration -defective battery, venting problem (if required), for example. However, BMW techs like to blame problems like this to the very first thing that they remember from tech school without a real root cause analysis of what's going on, IMO.

If the algorithm or whatever BMW uses to charge the battery has some "Jeckyl and Hyde" behaviors based on the OEM vs. an aftermarket battery replacement then we would have seen a raft of battery "explosions" in the last 5 years -since the introduction of the E90. I don't even think that most BMW owners know about battery registration, so there must be quite a number of BMW in the road right now with Wallmart, Sears and PepBoys batteries running around. Even if they know about battery registration still this is not going to be as big as an incentive to do the "right thing", just because the BMW dealer insists in charging up to $500 for a battery replacement/coding.

So we are back in square one... if this is as dangerous as it is being depicted then BMW and their dealers are not doing a good job in facilitating the compliance with this "requirement". I still think that battery registration is important, but not at the dealer with their absurd prices.

[ihyln]

I find it hard to believe that BMW could not engineer a system to know when a battery was replaced so it could charge/discharge accordingly. However, I would not put it past them to put this kind of money making scheme in place instead.

[gr8000]

Apologies if this is a dum question but can this coding be registered with Bavarian Technic (or a similar diagnostic tool)?

[aus]

Apparently the Bav Tech tool can "reset' the battery according to the E90 post thread.
The OP seems to have a regular lead acid battery too, so it's not even an AGM.

I'm pretty sure the newer model cars with stop/stop will have an AGM battery.

[cloud8r]

It sounds like there is an assumption amongst those pro-registration that the alternator's "intelligent recharging algorithm" stops being intelligent when the battery is replaced. If this "feature" does exist, then it should be monitoring the condition of the new battery just as it had the previous battery and continue to turn on/off the charging as needed. This features strikes me as something akin to the dct/auto tranny's adaptation where it would be ideal to reset/register but not absolutely necessary since it would eventually adjust. Sorry, I just cannot fathom there wouldn't be a basic battery charge level test, charge if volts < x, and if there isn't then BMW is responsible if not negligent for a huge design flaw. At minimum, similar to the motor oil, there should be a big WARNING tag on the battery stating that it must be serviced by BMW and that installing any other battery can cause serious damage.

So it just doesn't seem realistic to me that the cause of any of these exploding battery issues are related to any possible non-registration.

[Tim B.]

Originally Posted by ramyar

It sounds like there is an assumption amongst those pro-registration that the alternator's "intelligent recharging algorithm" stops being intelligent when the battery is replaced. If this "feature" does exist, then it should be monitoring the condition of the new battery just as it had the previous battery and continue to turn on/off the charging as needed. This features strikes me as something akin to the dct/auto tranny's adaptation where it would be ideal to reset/register but not absolutely necessary since it would eventually adjust. Sorry, I just cannot fathom there wouldn't be a basic battery charge level test, charge if volts < x, and if there isn't then BMW is responsible if not negligent for a huge design flaw. At minimal, similar to the motor oil, there should be a big WARNING tag on the battery stating that it must be serviced by BMW and that installing any other battery can cause serious damage.

So it just doesn't seem realistic to me that the cause of any of these exploding battery issues are related to any possible non-registration.

Totally agree......excellent post!

[JCtx]

It can't get much simpler than a freaking wet-cell battery (like stock) folks. If we buy the same type/size/rating battery (Walmart, Sams, etc), absolutely nothing will happen to it or the car. And no way the DME is going to 'know' the battery is not from BMW. I'd obviously sense it was disconnected, and apparently senses the new one has higher voltage if previous one was bad, but can't recognize a BMW one from an Interstate (or whatever) of the same size/type/rating.

Now, if doing that simple task happens to trigger any kind of warning that doesn't reset itself after a reasonable time, requiring a visit to a dealer (and $$$) to turn it off, this will absolutely be the last BMW in my household for the rest of my life. And would make sure none of my daughters buys one in their lifetime too, at least with my money . Talk about crossing the line between technology and highway robbery.

Curious to hear if an actual E9x M3 owner has done this, and what happened right after. And if warning lights, did they go out on their own after a 'learning' period?

The other thing we could do which doubt would trigger anything is to swap the battery while good, and fully charge it before the swap. I always do this myself, since for $100 or so, I'm not the kind to wait until I get stranded at the most inopportune time to replace a battery. I usually replace them every 4 years, while still good, but probably not much life left. Interesting thread. And hopefully BMW will read it, to take note this kind of crap hidden with the 'technology' label is for thugs, and enrages many owners. Take care gang.

[aus]

I'm with you, but this is what you get when you ask on the other side: http://www.e90post.com/forums/showpo...&postcount=229

.

[Merlin_83]

Originally Posted by Technic

Well, this is slightly more complicated than it seems.

The reason of the battery registration is that BMW uses an "intelligent" alternator variable algorithm that monitors the battery condition (charge, rate of discharge, etc) and simply shuts on and off depending on this condition. That reduces engine load thus increasing efficiency -power and economy.

When you replace the OEM battery you in fact are not telling that algorithm that the battery adapted values stored so far no longer apply -they were collected over a period of time from the old battery condition. So the "old" algorithm continues to do its job although the variable values changed. This could either under/over charge your new battery just because its charging/discharging characteristics not necessarily will have to match the old battery's.

So the sole purpose of the battery registration is to update that algorithm to the new values, by starting over the collection of adaptive values from the new battery so it is charged/discharged exactly -or close to it- to its most particular efficient capacity.

Sometimes it seems that the battery registration was not necessary when there are no problems with the new battery install. That's most probably due to the new battery condition pretty much matching the current alternator algorithm and that you are not asking too much from that battery... in other words, just luck. Sometimes it really messes up the new battery after awhile as the current algorithm keeps the battery under/over its real capacity.

My suggestion is simple... try to find an Autologic shop and get the new battery registered just in case. It takes less than 5 minutes -just press "Register" in the screen and that's it- and most probably the guy there will do it for free if you ask nicely (I did that). In the worst case is half an hour job or even less.

The dealer as always is making this like a big job which it isn't. By the way, I'm using a Sears Die Hard battery instead of OEM.

Agree with this - and makes sense, I work with electronics in my day job and indeed it does seem logical to 'clear' an old map or algorithm used by prior battery ampacity - for something as important and critical to all of the sensitive on board computers having a battery 'registered' by a trained tech is just the smart thing to do IMHO

Thanks,
Merlin