Excessive Battery Drain Fix from BMW AG

[MRV99]

The X5 is in for the ever so popular battery drain message and I come to find out that there may be some hope for us people who do not drive our X5's the way BMW recommends us to.

Since BMW has noticed a very large number of X5 owners experiencing this issue, BMW believes they have a fix to help reduce or help eliminate this problem. I was told the fix entails a new program which reduces the amount of time that the X5 says awake once the car has been turned off. The current software keeps the computer system(not accessories) powered for 30 min after the car is turned off to speed up the "boot process" for people getting in and starting there cars. Since the X5 has close to 60 computers, it consumes a great deal of power when the car is off. The simplest fix would be to change the charging parameter to have the alternator start to charge the battery at a higher level, but BMW has to keep the alternator use to a minimum to help meet federal fuel guidelines and they do not want to have lower the MPG ratings on the X5. Instead, they have now reduced the awake time from 30 min to 20 min. They say this has reduced the number of reported Excessive Battery drain issues by more than 1/2.

Once I get the X5 back from the dealer I will provide specifics form the work order and provide any SIB info which I can get. I will also keep people posted on if this fix works or not.

I am cross posting this on Bimmerfest