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Old 10-05-2012, 06:22 AM
avoiceoreason avoiceoreason is offline
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Location: PA
Join Date: May 2010
Posts: 64
Mein Auto: '07 650i convertible
Originally Posted by Yorgi View Post
Not sure where you heard that but I am almost 100% certain this is not true. It would mean the car does not charge when at idle and I know it does charge at standstill.
I could definitely be in the wrong here, but I seem to recall it having something to do with BMW trying to save an MPG or two by designing it this way.

Tampamark is likely more accurate in his description when he states that the alternator doesn't put out enough voltage to actually charge the battery at idle. Still curious as to what the trigger/tipping point is for the battery to actually receive charge while driving.

Originally Posted by Yorgi View Post
The short trips are your big issue. The car stays awake for 30-45 minutes at the end of the trip and drains the battery. If you don't take 30 min trips on a regular basis the battery will eventually go flat. BMW calls it an "unfavorable driving profile" if you take short tips daily and try to blame it on you instead of admitting the majorly screwed up on the design of the electrical system on these cars.
Amen to that! BMW doesn't like to take the blame for any poor design issue IMO unless they are worried they are going to get sued for the issue potentially hurting someone.

And the short trips could be the issue, and I'm sure that will be the response when I take it in. BTW, will they check the alternator proactively, or do I need to request it? Possbile they will just take the easy way out and point to the driving profile and leave it at that.

I am taking it in next week to have them look at it, along with another crack at the top not locked warning, and the battery cable recall. Sometimes I long for my old Honda Civic. (not sunny 75 degreee days like today though )

Last edited by avoiceoreason; 10-05-2012 at 06:29 AM.
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