[AWD Addict]

My mechanic has advised me that my battery is at 55%, and it's time to replace it. While it's been 5 years, which isn't an unreasonable life for a lead-acid battery, particularly in a car with as many electronic needs as this, is that really the case?

I actually continue to sleuth out my rough idle issues, now post warranty with a non-dealer BMW specialist nearby, and he suggested the battery could be the culprit.

Given my woes in this category have been in place since the car was new, I doubt that's the culprit, and the superceding battery is pretty spendy. If I can wait, I'd prefer it.

Thoughts?

[bigdnno98]

$450 battery replacement sucks but if BMW says replace it, I would. The car really goes crazy when the battery is low.

[BLK_08E90]

My battery recently died after little over 4 years. no symptoms just didn't start one day after a 4 days of not driving it (checked and no draw). Got a new one from my local pepboys for $139 with 3 year full replacement and up to 84 months prorated. Battery size group is 94R for FYI. Also if you have access to a BT tool, reset battery adaptation just in case.

[cleex024]

yeah but is there a better battery option than stock?

[Jeff@TopGearSolutions]

Once the temps drop even lower in your area a weak battery will usually just be dead in the morning (generally speaking).

5 years is a very long time for these batteries to maintain life so consider yourself lucky.

Be that as it may, where did your mechanic determine 50% life?

Last but not least, have you tested your batteries output at idle yourself and revving to 2000 RPM?

I believe it should be 14.2-14.5 Volts

With the car off it should be atleast 12.8

If you source the battery yourself and install it, all you need is someone to register it to the car, you may save quite a bit doing it yourself if you can find someone to register it for free or cheap.

[cstavaru]

You do not have to put in a BMW battery (which is usually made by Exide). Just get any battery and put it in, it will work, but it has to use the same technology (non-AGM vs. AGM). If your current battery has a status visor (eye) get any gel battery of the same dimensions and power. If it is AGM (doesn't have the status indicator) get an AGM battery. The battery registration thing is not needed if the battery capacity is the same as your current one.

[Jeff@TopGearSolutions]

Originally Posted by cstavaru

You do not have to put in a BMW battery (which is usually made by Exide). Just get any battery and put it in, it will work, but it has to use the same technology (non-AGM vs. AGM). If your current battery has a status visor (eye) get any gel battery of the same dimensions and power. If it is AGM (doesn't have the status indicator) get an AGM battery. The battery registration thing is not needed if the battery capacity is the same as your current one.

If that is true that is good info. Thanks

[Mike@N54Tuning.com]

Jeff is right. With cold weather coming a battery thats close to going out will most likely die very quickly.

Mike

[335xi Kevo]

While working on my meth system this past weekend, key on light on for maybe 20 mins, I killed my battery. I believe this to be a bit short do you think im a canidate for a new battery and if so, would CPO cover replacement?

[bs004417]

I went with the Pepboys route when my battery went out after 4 years. Working great so far.

[hasta la pasta 27]

read your codes. My misfire ended up being injectors 4,5,6 on an 09 with 55k miles

[Elliott@DetailAddict]

Originally Posted by cstavaru

You do not have to put in a BMW battery (which is usually made by Exide). Just get any battery and put it in, it will work, but it has to use the same technology (non-AGM vs. AGM). If your current battery has a status visor (eye) get any gel battery of the same dimensions and power. If it is AGM (doesn't have the status indicator) get an AGM battery. The battery registration thing is not needed if the battery capacity is the same as your current one.

False.
Registration records odometer readings as an internal maintenance record.
What you don't need to do if the battery is the same is to update the vehicle order and retrofit it in.

[AWD Addict]

Great info and responses. THanks much guys.

What about the new superceding part from the original OE Lead Acid battery? I can't find jack for info on the google. Pretty spendy.

And I have no idea how he came up with the 50-55% life. He advised me to have a couple long trips every week or so, maybe an hour to help keep it charged. I've had no other symptoms.

[AWD Addict]

Originally Posted by ericruiz911

read your codes. My misfire ended up being injectors 4,5,6 on an 09 with 55k miles

I don't have a misfire. I have a rough idle. Search for my thread on the matter. It's lengthy.

[CUTigers]

Who ever asked about CPO, I'm pretty sure they won't cover a battery. Not 100% sure though. Wear and tear item I assume.

[joro2077]

There is a good deal on everything at Advance Auto Parts - 20% off plus $50 gift card till 11/22/2012. I bought battery for $150 there is a$12 core charge so its gonna be 138 + $50 gift card = $88 total. Battery comes with 3 year replacement and 7 years warranty.

[litz4244]

There is so much misinformation on this forum. Me personally would go with a oem battery. You heard the saying you get what you pay for. But if you do get an aftermarket battery make sure the Cca is the same but more importantly ah has to be the same. Amp hour. That is critical. That's also how the battery is registered. You can register aftermarket batteries with the factory diag tools(isid). I strongly recommend registering the battery because when it is registered it resets the energy strategies in the dme. Charging strategy, power consumption strategy and so on. Weak batteries will cause reduced power to certain consumers if the battery gets weak enough and when registered it will reset all that.

[litz4244]

Sorry to continue on from my first post make sure the ah is the same. Most people think because the Cca is the same the ah is. Most of the time it isn't and with all the electronic on the vehicle when all is being used the aftermarket batteries can't keep up causing more problems and premature failure of that battery.

[MilehighM3]

Originally Posted by litz4244

There is so much misinformation on this forum. Me personally would go with a oem battery. You heard the saying you get what you pay for. But if you do get an aftermarket battery make sure the Cca is the same but more importantly ah has to be the same. Amp hour. That is critical. That's also how the battery is registered. You can register aftermarket batteries with the factory diag tools(isid). I strongly recommend registering the battery because when it is registered it resets the energy strategies in the dme. Charging strategy, power consumption strategy and so on. Weak batteries will cause reduced power to certain consumers if the battery gets weak enough and when registered it will reset all that.

+1
With the DME's charging strategy being adaptive, it increases the alternators charging output voltage and amperage to attempt to revive the worn battery and insure the starting ability of the car. Too many times I've seen a new battery be overcharged and damaged as a result of not registering it. If you do upgrade to an AGM style battery, retrofit coding IS necessary as the charging strategy is different than that of a traditional battery.
The battery is the most important part of your car, period. You choose if it's worth it to cheap out on something you depend on 100% of the time you drive your car. For me, no way this is something I'll be cheap about!

[litz4244]

Originally Posted by Bmw135er

+1
With the DME's charging strategy being adaptive, it increases the alternators charging output voltage and amperage to attempt to revive the worn battery and insure the starting ability of the car. Too many times I've seen a new battery be overcharged and damaged as a result of not registering it. If you do upgrade to an AGM style battery, retrofit coding IS necessary as the charging strategy is different than that of a traditional battery.
The battery is the most important part of your car, period. You choose if it's worth it to cheap out on something you depend on 100% of the time you drive your car. For me, no way this is something I'll be cheap about!

Yup it could deff over charge the new battery. I figured I rambled on enough. There is alot more to it the. People realize. That's what I did to my car. Since it sits for weeks at a time I put an agm bat in

[joro2077]

Of course you have to register the battery but other than that if its with the same parameters (ah, CCA..) it doesn't matter if its original or not its just a battery (you'll may get an extra year with OEM but not for sure and its gonna cost you at least 200-400, I've had an aftermarket battery before and it was good for the 4 years I had the car) battery technology in general is years back from everything else. Just my 2 cents

[litz4244]

Originally Posted by joro2077

Of course you have to register the battery but other than that if its with the same parameters (ah, CCA..) it doesn't matter if its original or not its just a battery (you'll may get an extra year with OEM but not for sure and its gonna cost you at least 200-400, I've had an aftermarket battery before and it was good for the 4 years I had the car) battery technology in general is years back from everything else. Just my 2 cents

For me most part Aslong as you get the correct ah battery and get it registered you will most likely be fine. I still suggest an oem battery. Sometimes u will be fine and sometimes not. No way to tell unless u have a magic crystal ball. Just remember you get what you pay for..