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7 Series - E65 / E66 (2002 - 2008)
Discussion of BMW's 4th generation E65/E66 7 Series flagship. The E65 generated much controversy, due to its radical styling and iDrive user difficulties. Nonetheless, the E65 broke records to become the best-selling 7-series iteration ever, especially after its 2005 facelift.

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Old 04-04-2010, 11:30 PM
sabertouch sabertouch is offline
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Location: midwest
Join Date: Apr 2004
Posts: 9
Mein Auto: 745li
Unhappy 750 battery life issue

Had to have my 2007 750 battery replaced late Dec because of a bad cell. It had been giving me intermittent problems for 5 months. Had 19k miles on car when replaced. BMW regional refused to warrant it so it cost me $250 for the battery and $178 for install.
Was in shop for several days to have past 30 days driving pattern analyzed and back and forth communication between dealer and regional, and check out of possible electrical drain.
Said the low mileage on car indicated it was not driven enough and too many short trips in last 30 days which would not allow the battery to completely recharge itself after start drain. Said it takes 5 miles of nonstop driving to replace one start. It will not recharge at idle. Car was ED and was picked up 2.4 months from replacement date.
Dealer said regional was no longer warranting batteries in BMW's. Appears the driving pattern
data and low mileage reason was just an excuse. Oh, the second battery had a bad cell and had to be replaced in less than a month. They had to warrant it, but still did the same checks as before.
The owners manual only says to drive high speed long trip a few times a month. BMW now says to do this several times a week. Wonder if the AGM batteries are more sensitive to multiple discharges. My 2004 745 never had any issues for the 3+ years of driving and it was also low mileage and same driving pattern.
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Old 04-04-2010, 11:42 PM
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robohopar robohopar is offline
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Location: SoCal
Join Date: Aug 2009
Posts: 872
Mein Auto: 06 750Li
wow, if what they say is true...its the stupidest thing I've ever heard in my life.

how can one that owns a $90k+ luxury car be obligated to drive a few long trips a month to keep its battery charged??!?

2006 BMW M5
SOLD: 2006 750Li Monaco Blue/Black|Sports Package|Convenience Package|Comfort Access|Logic 7|Rear Entertainment|Night Vision|SAT/HD|Cold Weather|Luxury Seats|Rear Power Sunshades|35% Tint|22" Custom Wheels|H&R's|Alpina Trunk Spoiler| ACS Roof Spoiler| MTEC v3|
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Old 04-05-2010, 05:41 AM
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GeorgeT GeorgeT is offline
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Location: Seneca, SC
Join Date: Jun 2007
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Mein Auto: '07 750i BMW; '03 Z4 BMW
My '07 has less than 23,000 miles and is driven about once a week on short trips and about once a month on a 200+ mile trip; it often sits 2 weeks without starting and have not had any battery issues to date (with my luck, however, the battery will be dead when I next get in).
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Old 04-05-2010, 07:25 AM
TechFreak TechFreak is offline
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Mein Auto: AC Schnitzer 745i Sport
If your leaving the car for any period of time your supposed to flick the Battery Switch in the Trunk/Boot beside the fuse box to conserve it's power.
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Old 04-05-2010, 04:45 PM
sabertouch sabertouch is offline
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Location: midwest
Join Date: Apr 2004
Posts: 9
Mein Auto: 745li
Angry 750 battery life issue

If your battery dies on you with only 23,000 miles on the car, you can bet BMW will not replace
it under warranty just like mine. They said the battery will suffer if parked for long periods of
time because there are electronics in the car that continue to draw down the battery capacity.
They also said that after the car is shut down, the computers and modules continue to be powered on for 20 mins or so. Therefore, if you start and shut down the car several times and don't drive long enough at a high rpm, the battery will always be partially drained and it's life will be severely shortened. At least that's the company explanation to me.
So why don't they put this warning in the manual or send a notice to owners rather than keeping it quiet.
My lease ends very soon and I was planning on getting leasing my third BMW 7. Now after this experience I'm going to look at the competition for sure. I really think BMWNA is trying
to lower their warranty costs and is using explanations like this as justification. Why don't they recommend a trickle charger be used in these cases??
I have a 10,0000 per year lease and can't drive the mileage requirement [12-15k/year] they
use as justification to not warrant the battery. They said this car is designed to be driven at highway speeds not primarily for city use speeds. I do drive this car at highway speeds for at least 20 mins several times a week, I guess that's not good enough to keep the battery fully charged no matter what the owners manual says.
If the 07 electronics place a high load on the battery, just think what the latest model does with it's more complex and plentiful electronics.
Sorry for the vent, I have gone through the appeal channels and have been given the same story
for the non coverage. I love driving these cars, but this one really got to me. I going to take a test drive in a Mercedes S class and then an Audi A8 after my taxes are completed.
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Old 12-16-2012, 03:58 PM
bmrfan4 bmrfan4 is offline
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Location: Mechanicsville
Join Date: Dec 2012
Posts: 1
Mein Auto: 2008 750li
750li battery drain issues

I have 750li currently in shop with dead battery issues. Brand new battery replaced two weeks ago by local bmw dealer, two days later battery drained after sitting for 48 hours. May be issues with CA door handles. is this covered by the cpo? DEALER put me on loaner 2013 3 series
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