Battery Replacement Tips, "Register Battery Renewal" after replacing?

I replaced the batter on my early 2006 325i today. I noticed that there is a ton of posts about replacing batteries on the forums in the last few days, and I thought it would be good to share some tips below.

For the last few weeks, I've noticed longer cranks when starting the car. It's been getting colder around here, so I figured it was due to the temperature change. Throughout the week, I noticed a few other strange things happening. The heater fan would only blow at 50% speed (but the defroster would blow at 100%). The stereo went silent for 10 seconds while I was switching between aux input and radio. The REST function would work 20% of the time. All lights on the dash would strobe on and off whenever I started the car in the morning.

The strange problems started adding up, so I figured it was time for a new battery. I went to Autozone and picked up a 49-DL series battery for $90.

A few pointers:

• The OEM battery is 48-DL, but the larger 49-DL will fit correctly.
• The OEM battery (and 48-DL size battery) uses a Styrofoam pad and to hold it in place in the battery tray. The pad is in the rear of the tray, towards the back of the car. The larger 49-DL will mount using the same bracket without the padding.
• The OEM battery is slightly taller than the 49-DL. I placed a small block of wood on top of the battery under the holding bracket.
• The Autozone Duralast 49-DL comes with a vent hose extension, but it is not long enough for the E90. I went to Lowes and bought the thinnest plastic hose I could find in the plumbing department. I needed to create a 6 inch extension. (I bought 4 feet for future projects. It was 16 cents a foot, and it's good to have around.)

The big question is:
Do you need to take the car to the dealership to perform a "register battery renewal?"

Several DIY guides and forum posts state that the dealership needs to hook up their diagnostic tools and perform a "register battery renewal" procedure to tell the car's ECU that you replaced the battery. I have read that the dealership and third party service manuals state that this is necessary and that the car may damage the new battery if the registration procedure is not followed. I have also read that people have just replaced the battery without any issues.

I have not performed this procedure yet. I may purchase a Bavarian Technic ("BT") diagnostic cable so that I can perform this procedure myself without going to the dealership.

Question: Has anyone damaged a battery after replacement without performing the "register battery renewal" procedure? Has anyone replaced their battery without any issues?


I'm interested to hear actual cases here. I understand all of the claims. I have yet to see a post explicitly stating that someone replaced their their battery without the dealership and the battery was damaged by the car. I find it hard to believe that this could happen. It would be good to hear from anyone with actual experiences here.

One additional comment:
The Duralast 49-DL was a DIY'er favorite for the E46, which is why I tried it on my E90.

I previously tried to use a 49-DL on my E46 convertible, but I could not get it to fit in the battery tray. I found out that the E46 convertible has a smaller battery tray than the E46 sedan and coupe. I would not be surprised if the E92 battery tray has the same issue, but I don't have an E92, so I can't confirm.

I used a smaller sized battery (recommended by Autozone database -- I forget the size) in the E46 convertible without any issues.

My Bentley Manual says registration is needed to delete accumulated information on the old battery so proper charging values may be used on the new battery. I am guessing this means that w/o the registration the charging system will treat the battery the same as the old one and possible not fully charge it, or charge using the incorrect voltage, leading to premature battery failure which may not become evident for several months or years. Your Group 49 battery has a higher ampere hour rating than the old one and that is also supposed to be input as part of the registration. One other issue you have is your prior battery was doubtless an AGM battery, which you have replaced with a "flooded" model. It is possible that the your car should also be registered because the different types of batteries have slightly different charging voltages and allowable amperage. This info is just from my own research - it would be nice if a real BMW technician could answer your question.

A couple of things... the replacement battery is NOT a 48DL, the correct size is a group 48. I found this out the hard way.

I read the Bentley manual and wondered about "registering" the battery, in real life that doesn't seem to be necessary.

Please read the DIY battery replacement thread and add any information you may have.

Foreign Service
Motor, Jun 2009 by Marinucci, Dan

Vehicles are becoming increasingly self-aware with each passing yean Its no longer enough to replace a battery when necessary. Many late-model BMWs also need to know whenyou replaced it

Last month I discussed a timely trend in higher-end European electrical systems, the absorbed glass-mat (AGM) battery. This time I'll focus on another one, relearning BMW charging systems after battery replacement. You read correctly - relearning the charging system.

First I'll recap the AGM battery information. An AGM battery is more damp than wet inside because it isn't flooded with liquid electrolyte like a traditional battery is. Also, AGMs are designed to be very low-gassing batteries. These features make them especially well-suited for locations inside the vehicle. Some higher-end European vehicles have an AGM battery somewhere inside the vehicle powering on-board electronics while a separate battery under the hood handles starting duties. Finally, fully recharging an AGM battery safely and quickly requires an AGM-capable charger.

Okay, let's get back to those late-model BMW charging systems. First, the electrical system is so sophisticated that it tailors charging as closely as possible to both the type and the age of the battery. There's a computer, which goes by several different names, that controls the alternator. Whenever you replace a battery, this computer really needs to know because it doesn't charge a fresh battery the same way it charges an older battery. What's more, this computer needs to know if you've updated a vehicle from a conventional battery to an AGM type; it charges the AGM differently than a traditional battery.

Second, the process of updating this alternator-control computer is called battery registration. You don't ab- solutely have to register every new battery you install in these late-model BMWs. Ignoring the registration process after replacing a battery won't trigger a DTC or turn on the MIL. Howev- er, a savvy BMW specialist warned me that skipping the battery registration process can dramatically shorten the life of a battery in these vehicles, be it an AGM or a conventional battery. For instance, he's diagnosed cars on which a new battery didn't even last a year because it wasn't registered! The charging system could shorten the life of an unreg- istered battery by charging it too aggressively when it's cold; it also could shorten the life of an unregistered AGM battery by overcharg- ing it, he said. To say the least, premature battery failure can be aggravating for the customer and embarrassing for you and your shop.

Third, several problems can cause premature battery failure. On a latemodel BMW, skipping battery registration can be one of them. Don't gamble; always register a new battery on any BMW equipped with MOST Bus - a single-line, fiber-optic ring network BMW introduced in the early 2000s. Typically, the easiest way to identify a vehicle equipped with MOST Bus is to look for iDrive. In turn, the quickest way to spot iDrive is to look for the fancy LCD control display screen up on the instrument panel. Among other things, this display screen shows the driver climate control functions, navigational info, entertainment system controls, etc. (To my knowledge, the lone exception to this is the 2006 3series cars without iDrive, which still use the MOST Bus network.)

Here's when MOST Bus appeared on the most common BMWs your shop would encounter:

* 2002 for 7-series (E65/66 vehicle platforms);

* 2003 for 6-series (E63/54 vehicle platforms);

* 2004 for 5-series (E60/61 vehicle platforms);

* 2006 for 3-series (E90/9 1/92/93 vehicle platforms);

* 2007 for X5 series (E70 vehicle platform);

* 2008 for X6 series (E71 vehicle platform).

Fourth, registering a battery is easy but it requires a scan tool that communicates effectively with these BMWs. If you want to service more of these vehicles, shop for scanner updates or a new scan tool that will do the job. The screen capture on page 10 from an AutoLogic scan tool is an example of one of those you'd see during the battery registration. You also could look up battery history on this same screen. Notice that the first entry is "Last battery replacement (km)"and the reading is 0.00. Meanwhile, all the remaining entries are the same value of 528,392 km (about 328,000 mi.). These readings show that if someone has replaced this car's battery, he did not register it.

One BMW specialist pointed out to me that sometimes you can quickly check to see if the car's got the original battery in it. He said that BMW traditionally stamps the battery's manufacturing date on the negative terminal. The date stamp shows the week first, then the year. For instance, "42 05"indicates the 42nd week of 2005; "33 07"would mean the 33rd week of 2007. If the date stamp on the negative battery terminal is fairly close to the vehicle build date, then it's extremely likely that it's the original battery.

Look at the screen capture again. The BMW ace told me that if the battery had been replaced and registered correctly, the number in the top box or window would be 1.00. Next, the second entry there would be the kilometer (km) reading when the new battery was registered. Then, the rest of the entries in those little windows would show the vehicle's then-current km (odometer) reading.

Great reply -- tons of useful information in there. This pretty much summarizes the information I've read throughout this forum (and a few others).

I still haven't been able to find a case where someone killed their new battery by not "registering" it with the ECU. There's tons of "I heard this" and "I know someone who did that" posts, just nothing concrete.

If the Bavarian Technic cable was not limited to 3 cars, I would buy one and do it myself. There are four BMWs in my immediate family, and I'm finding it really hard to justify a $300 diagnostic tool that I could not use on all four cars.

Well my battery is acting like it's about to go also. To reiterate, do I replace it myself, then take it to the dealership for registration?

Wow! No wonder BMW has so much troubles. Simple battery change is that complicated!

I was under the impression from various posts that older cars like your 2006 model, did not need battery registration. I have a 2007 328i and called my dealer and asked him if registration would be necessary if I replaced my battery. He said it was not required on my model.

Aside from the questions about the battery registraion process, did the new battery solve the problems your car had developed?

Originally Posted by Raymond Lee

Wow! No wonder BMW has so much troubles. Simple battery change is that complicated!

Not really, AGM type batteries have a very long lifespan provided the proper steps are followed during battery replacement.

Originally Posted by w5lx

I was under the impression from various posts that older cars like your 2006 model, did not need battery registration. I have a 2007 328i and called my dealer and asked him if registration would be necessary if I replaced my battery. He said it was not required on my model.

All e9xs require battery registration when the battery is replaced.

I am beginning to think that registration is required on the E90 because my battery is dead. I bought the car used so this is new to me. But using the article posted, I looked at the negative terminal on my battery and it's posted 33 09. So that means the battery must have been replaced in 09. With that said, here it is early 2011 and my battery is needing replaced. That is telling me the information about registering a battery is true because this new battery has not lasted.

If you think BMW battery changing is unique, you are wrong, MB/Audi and host of others are too. And just wait a decade, when batteries in cars are the motor, thats another can of worms a PHD will be required.

I've never believed a battery can be 'maintenance free', in that the water level never needs to be checked. Is there a way to check the water level in the factory battery of a '10 328?
Thanks for any guidance provided.

Someone over on e90post had his battery explode in his trunk after replacing. I believe it was traced back to not registering it.

http://www.e90post.com/forums/showthread.php?t=468750

Originally Posted by blauner

Someone over on e90post had his battery explode in his trunk after replacing. I believe it was traced back to not registering it.

http://www.e90post.com/forums/showthread.php?t=468750

Actually, it was NOT the battery that exploded. It was the battery regulator box that was attached to the battery.

"Hi ENINTY, the battery itself did not explode. There was no battery acid spewing all over or anything like that. I guess I should have been a little more thorough in my description. I believe it was the power regulater that actuallyexploded whic is waht attaches to the smart pack."

Originally Posted by w5lx

Actually, it was NOT the battery that exploded. It was the battery regulator box that was attached to the battery.

"Hi ENINTY, the battery itself did not explode. There was no battery acid spewing all over or anything like that. I guess I should have been a little more thorough in my description. I believe it was the power regulater that actuallyexploded whic is waht attaches to the smart pack."

Correct. Also there was no evidence it was related to not registering.

I wonder if the battery explosion was related to not hooking the battery up to the exhaust hose? A build up of hydrogen would ignite like that I would think. I just replaced my battery a week ago - so far so good. I asked the dealer's service receptionist if they would reset the battery charging levels in the computer, but she said they would only do it for OEM batteries and they do not support mine. I am waiting on a callback to see if that is correct - she is checking with the service techs. Hopefully that person was just wrong and they will do it, I just flat out do not want to buy a Bav Tec tool, but I will if they will not do it for me.

I see some people are wondering whether battery registration needs to be bothered with. Apparently yes, it does.

I replaced the original battery on my 2006 E90 myself in 2010, figuring it must be due, especially since the Florida heat tends to be tough on batteries. I had read a number of DIYs and never saw anything about registering the battery (never heard of such a thing until today). Within 6 months or so the car was cranking slow. By late summer 2011 the battery went completely dead. I put another new battery in myself (this was just a few months ago). Within weeks I noticed the cranking was somewhat slow again. I started thinking maybe the ignition coils are getting old. Today I've got the car in a good local shop for a rear window regulator replacement (damn those windows). Just got a call --- the battery is bad and the car wouldn't crank. The subject of "registering the battery with the car" then came up and was explained to me. So in addition to the window repair job I'm having them put in a new BMW battery and do the registering

This is what you call learning the hard way that the car's design is too "advanced" for the owner's own good. Bottom line is I would recommend taking care of the registering.

I originally started this thread about 2 years ago (and I didn't even remember until I looked over in the left column).

I did not register my battery on my 2006 E90. I have had no issues over the last 2 years. Your mileage may vary.

I plan on getting a USB/CAN cable so that I can properly register the battery myself in the future, but it has not made any obvious difference so far. I don't remember if my car came with an AGM battery - I believe this could make a big difference.

Does anyone know how much the dealers charge to "register" a battery replaced by the owner?

Thanks!

While I admire the OP's willingness to go the extra mile for a DIY battery change (and it's great to hear he has had no problems without registering), I just don't understand why it's "worth it". I understand saving money and not being willing to overpay at the dealer. However, since the OP and many here are willing to use an aftermarket battery, why not just go to a BMW independent mechanic and let them put in an aftermarket battery and register it for you. A decent shop will have the proper replacement for your particular vehicle, they can power it up during the change to not lose any settings, etc, and they have the hardware/software to do a proper registering.

I did this 6 months ago for my e90 and it only cost a few hundred$, probably about 60% of the dealer charge and not much more than the cost for the battery. just my 2 cents.

I have a 2007 328i with premium package. I still have the original battery. Best investment you could make - buy the BMW trickle charger. When I go 2 days or more without driving my BMW, I hook it up to the trickle charger overnight, or leave it charging when I'm on an out of town trip. Remember that all of the electronic gizmos in the premium package use alot of battery power.

Happy Driving!

Originally Posted by Munich2006

I see some people are wondering whether battery registration needs to be bothered with. Apparently yes, it does.

I replaced the original battery on my 2006 E90 myself in 2010, figuring it must be due, especially since the Florida heat tends to be tough on batteries. I had read a number of DIYs and never saw anything about registering the battery (never heard of such a thing until today). Within 6 months or so the car was cranking slow. By late summer 2011 the battery went completely dead. I put another new battery in myself (this was just a few months ago). Within weeks I noticed the cranking was somewhat slow again. I started thinking maybe the ignition coils are getting old. Today I've got the car in a good local shop for a rear window regulator replacement (damn those windows). Just got a call --- the battery is bad and the car wouldn't crank. The subject of "registering the battery with the car" then came up and was explained to me. So in addition to the window repair job I'm having them put in a new BMW battery and do the registering

This is what you call learning the hard way that the car's design is too "advanced" for the owner's own good. Bottom line is I would recommend taking care of the registering.

I’m thinking by registering the battery it resets the adaption to control charge current and voltage. If charge current is increased to maintain a weak battery then if you use the same charging cycle on a new battery the result is outgassing the new battery. (i.e. venting the hydrogen and oxygen from the battery.) This eventually leads to premature failure. Bottom line there is a reason to register the battery.

Did it on my 07 328i e92 with INPA the other day. $169.00 + tax for OEM battery at dealership and $90 bucks for a K+DCan cable. Cable originally use to fix steering angle sensor.

Originally Posted by yikes98

Did it on my 07 328i e92 with INPA the other day. $169.00 + tax for OEM battery at dealership and $90 bucks for a K+DCan cable. Cable originally use to fix steering angle sensor.

So this INPA K+DCAn thing will register the battery? It looks like it's less than $100 versus $300 for the BT tool.

My local dealer wants $540 plus tax to swap the battery in my 330xi. He won't break it down for me, but says that includes "2-4 hours of programming" at $135/hour. When pressed, I asked if the extra programming is because he's switching from the stock lead acid battery to an AGM battery. He said yes. He won't consider putting a lead acid battery in the car.

So my dilemma is this. The car has the bigger 720 CCA, 90 Ah battery in it. The Autozone battery is only 600 CCA. NAPA sells one that is 700 CCA, which I think is close enough. But it sounds to me like the car will still need "programmed" with the new battery specs rather than just "registered", right?