balbs

Look at those threads again. Are they saying something like "I'm on my non-oem non-registered battery for a few months now and no issue"...or "6 months now and no issue" or almost a year. I've never seen one saying "I've had mine for the last 2 years and no issue".

However, I have seen "I changed my battery a year ago and now I'm having electrical issues".

I went through the same steps as you before earlier this year when getting a new battery for my car.

Here's a thread where someone with a relatively new non-registered battery that has issues:
https://5series.net/forums/topic/117...1#entry1388678





^^This...One of my hobbies is RC Helicopters. I have a $200 computerized charger to properly charge my batteries so that they don't blow up or overheat. It also helps them last longer. I figure the E60's electrical system is more complex than that.

V70Cat

I don't understand the register issue if the battery is the same type (oem I would assume is wet and not glass) and the same capacity the computer should already have that same information with regard to charging?

balbs

To be honest, me neither...However, when I was getting mine registered, the tech mentioned inputting the date when the battery was installed so that it would charge it properly. I guess it's so the system will know if it's charging an old battery vs. a new one. Meaning it might under charge a new battery thinking that it's still the old one installed.

Edit: at least that's my interpretation of it. I could be wrong. But he did need to enter the date.

V70Cat

Does not make sense it would seem that all the computer can read is voltage; still don't understand what it can do with the other information like capacity and age? Maybe it is related to normal discharge load and voltage when parked but all that does is send a message/warning if it out of the normal range. It sure seems like a reason the dealer to charge you but other than that it just does not make sense?

Does the manual talk about registering the battery? Is this a issue for just BMW?

balbs

The computer can read more than just voltage. Take a AAA battery and a D battery. Both have 1.5V however the D cell has more amperage (capacity). There's also a measurement of a battery's discharge rate. Suck too much power from an improperly charged battery and it can overheat and blow up in extreme cases.

V70Cat

I found this site that might help

http://www.trademotion.com/shoppingc...6catalogid%3D2

It seems to indicate that the full retail price is $240. If it the exact battery with no need to reprogram it not a bad price. The price through this site is $187 plus $15 shipping. The shipping charges is about the same as sales tax, not a bad deal.

I have changed many batteries in my life and do not consider it hard to do (have not done a BMW battery). You might need a terminal cleaner and or some sand paper if the cables have corrosion. I plan to change the battery on my car once it is 5 to 6 years old. I will do it on a nice warm day and therefore not have to do it in the dead of winter. I think the OP asked if he should change the battery the answer to me on all cars is yes at signs of weakness or when the battery becomes older (5 years old). To me $200 is well worth the cost of knowing that my car should start on a cold winter day. If you can't spring for $200 dollars you should not be driving a BMW!

vkhong

- The size (capacity) of the battery required for the car is coded in the Car Access System (CAS).
- Use the battery size (capacity) installed as standard when replacing the battery.
- Recode the Car Access System (CAS) when installing a battery with a different capacity.

BMW TIS - 61 12 ... General information on intelligent battery sensor (IBS)

vkhong

The IBS uses the battery capacity information (coded in the vehicle) to keep a running tally of the state of capacity and the state of health. When limit of starting capability is reached, the IBS sends out a message so that non-critical components can shut themselves off to preserve cranking power. The IBS almost never goes to sleep, waking up every 14 seconds to read the battery state. It also monitors and controls the charging rate. History is kept of battery activity and status. This is the reason why the system needs to be informed when a fresh, new battery has been installed, so that it relearns the characteristics of the new battery using the base assumption whether it is a lead-acid or AGM battery of a certain capacity. IBS reset does not occur simply by disconnecting the battery, as this would cause the IBS to erroneously reset when the cable is disconnected for certain vehicle service procedures.

V70Cat

I agree that you would need to reprogram if changing battery types but if you stick with what you have I don't really see the issue. The computer will see a strong battery and charge it. I guess that it could think that the battery has less starting capacity but what is the down side of reducing peak demand?

SiM SiMMa

i had the same issue a couple years ago. every place i checked online, they wanted over $200 for a new battery. so i just went over to Lappen's auto part store and bought one for $150 installed. the only thing different is the size, its a bit smaller, and the CCA's (cold cranking amps). the factory one was 900 CCa and the one i got was 750 CCA (which is still good for our New England weather). anyway, it works great, no dealer programming or anything. i'm sure you could find one at AutoZone or some place like that for the same price or cheaper. if i were you, i would check the local auto parts stores before you order one online and pay extra money for nothing, they come with a good warranty anyways. Good Luck!