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jbehler
05-05-2010, 06:59 AM
I came out from the gym this morning and my keyless entry didn't work. I opened the doors manually. Car started up fine, but the radio presets were all erased. Interestingly, the seat memory, date, and time were not affected. The battery is original and will be 6 years old in November. Could this be caused by a battery nearing the end of it's useful life?

djfitter
05-05-2010, 07:25 AM
I came out from the gym this morning and my keyless entry didn't work. I opened the doors manually. Car started up fine, but the radio presets were all erased. Interestingly, the seat memory, date, and time were not affected. The battery is original and will be 6 years old in November. Could this be caused by a battery nearing the end of it's useful life?

Not could be, it IS!!!

dj

w5lx
05-06-2010, 09:35 AM
Those are all signs of a weak battery and impending failure. Time to get a new one. 6 years of service is excellent. Hope mine lasts that long.

jbehler
05-06-2010, 09:42 AM
Those are all signs of a weak battery and impending failure. Time to get a new one. 6 years of service is excellent. Hope mine lasts that long.

Replaced it last night thanks to the fine folks at Batteries Plus. 20 minutes for change, update clock, and reset active steering reset. $146 total vs. $450+ at dealer for OEM battery plus "registration".

w5lx
05-06-2010, 10:39 AM
Replaced it last night thanks to the fine folks at Batteries Plus. 20 minutes for change, update clock, and reset active steering reset. $146 total vs. $450+ at dealer for OEM battery plus "registration".


Great price. Did that include registration of the battery? Do they have the necessary equipment to do that?

jbehler
05-06-2010, 11:22 AM
Great price. Did that include registration of the battery? Do they have the necessary equipment to do that?

That was just the battery. I did the install myself. It did not include 'registration', which I believe is BS. Apparently some have been told that the alternator charges differently based on the age of the battery, but talking to a friend of mine who is an automotive engineer it sounds like this is highly unlikely. All alternators apparently sense the pull from the battery and adjust accordingly. My guess is that BMW's 'registration' is really them updating the date/clock and the active steering warning.

bimmerguyjoey
05-06-2010, 12:12 PM
Replaced it last night thanks to the fine folks at Batteries Plus. 20 minutes for change, update clock, and reset active steering reset. $146 total vs. $450+ at dealer for OEM battery plus "registration".

$450! Holy cow! No wonder people are so tired of dealers sometimes. Good to know you can DIY for a lot cheaper.

Can you tell me where you ordered the battery from? Website or local aftermarket store? Or was it BMW OEM battery?

djfitter
05-06-2010, 12:17 PM
Replaced it last night thanks to the fine folks at Batteries Plus. 20 minutes for change, update clock, and reset active steering reset. $146 total vs. $450+ at dealer for OEM battery plus "registration".

$450! Holy cow! No wonder people are so tired of dealers sometimes. Good to know you can DIY for a lot cheaper.

Can you tell me where you ordered the battery from? Website or local aftermarket store? Or was it BMW OEM battery?

It had to be a local acquisition, not enough time transpired for it to be a website purchase.

dj

jbehler
05-06-2010, 12:49 PM
It had to be a local acquisition, not enough time transpired for it to be a website purchase.

dj

Correct. I called my local Batteries Plus franchise and they had one in stock. After printing out a 10% off coupon it was cheaper than Autozone, etc. I went with Batteries Plus as their warranty and customer service are unmatched.

It was an aftermarket battery, you can only get BMW batteries through a dealer to my knowledge.

w5lx
05-06-2010, 12:58 PM
I recently called 4 dealers in the DFW area for quotes on battery replacement on a 2007 328i.

1st dealer quoted $450
2nd dealer quoted $550
1st aftermarket BMW shop quoted $350
2nd aftermarket BMW shop quoted $180

All quotes were for original replacement BMW batteries with registration included.
All shops told me batteries must be registered to the car so the "smart alternator" would recognize the new battery and charge it accordingly. The quote at $180 comes from an independent BMW shop with a good reputation. I will likely deal with them when the time comes.

mleerob
05-06-2010, 01:29 PM
I recently called 4 dealers in the DFW area for quotes on battery replacement on a 2007 328i.

1st dealer quoted $450
2nd dealer quoted $550
1st aftermarket BMW shop quoted $350
2nd aftermarket BMW shop quoted $180

All quotes were for original replacement BMW batteries with registration included.
All shops told me batteries must be registered to the car so the "smart alternator" would recognize the new battery and charge it accordingly. The quote at $180 comes from an independent BMW shop with a good reputation. I will likely deal with them when the time comes.

That's why I typically stay away from dealers.
Wowever I plan to keep this car under warranty,and at the dealer with any problems.
Just under 30K miles now.
Except a sunroof anjustment,and the iPod malf, all is great with this car.
Need to check my battery.
Still have not removed the panel to look at it.

jeffbtx
05-06-2010, 04:23 PM
That was just the battery. I did the install myself. It did not include 'registration', which I believe is BS. Apparently some have been told that the alternator charges differently based on the age of the battery, but talking to a friend of mine who is an automotive engineer it sounds like this is highly unlikely. All alternators apparently sense the pull from the battery and adjust accordingly. My guess is that BMW's 'registration' is really them updating the date/clock and the active steering warning.

Not sure exactly what is involved in registration. My understanding is that ECU can adjust charging rate to help save fuel by reducing the power drain of running the alternator - even my Suburban has this now. The "smart" alternator doesn't adjust for age of battery but based on some variety of parameters reduces the charging.