Battery Issue

[cuban_bmwx5]

hey guys
so i have a issue with my X5 for some reason i have to boost it pretty much all the time i boost it on saturday then sunday i start it up fine then monday dead..
i got a new battery installed from bmw dealer and they did a test on the alternator they said it was fine so this issue got me stumped.. now what i want to know is a friend on mine has a e39 and he said he had the same issue some one told him it was the blower regulator he fixed it and now its fine. could that be my issue as well? just wanted to see if anyone else has dealt with this same issue.
thanks hope some one can help me out
(oh and the blower regulator is number 2 on the pic)

[Crowz]

There are soooo many things in an e53 that can kill the battery. Mine was the Bluetooth module (tcu). Unplugging it is a simple test to see if that's the issue on it but again there are tons of possibilities.

But if you have the Bluetooth unit its a good a place as any to start. Search the forum for what to unplug there are post with pictures of it.

[Fifty150hs]

Originally Posted by Crowz

There are soooo many things in an e53 that can kill the battery. Mine was the Bluetooth module (tcu). Unplugging it is a simple test to see if that's the issue on it but again there are tons of possibilities.

But if you have the Bluetooth unit its a good a place as any to start. Search the forum for what to unplug there are post with pictures of it.

The three most common causes of parasitic drain are the TCU, The Nav (if you have it) and the FSR. Pull one fuse at a time and you will find the cause. My money is on the TCU (fuse 74) as that seems to be the most common cause. Pull the fuse and see if that solves your problem.

[cuban_bmwx5]

Originally Posted by Fifty150hs

The three most common causes of parasitic drain are the TCU, The Nav (if you have it) and the FSR. Pull one fuse at a time and you will find the cause. My money is on the TCU (fuse 74) as that seems to be the most common cause. Pull the fuse and see if that solves your problem.

my x5 did not come with nav stock .. my aftermarket unit does have one tho

[Crowz]

Originally Posted by cuban_bmwx5

my x5 did not come with nav stock .. my aftermarket unit does have one tho

You can have Bluetooth without nav. Overboost's X5 is like that.

[omodos]

ok have to concurr with other posters here, alot can cause a drain , either way I have seen a tis I found that tells you 40ma is the drain you should be getting when e53 sleeps. Mine is at 50ma and just cannot get it lower, my 'drain' problem accompanied by lazy starts (getting worse and worse at this time of year) was my starter, without a shadow of doubt, since i changed it 24 days ago i have had no issues, wish i had done it years ago.

[cuban_bmwx5]

Originally Posted by Crowz

There are soooo many things in an e53 that can kill the battery. Mine was the Bluetooth module (tcu). Unplugging it is a simple test to see if that's the issue on it but again there are tons of possibilities.

But if you have the Bluetooth unit its a good a place as any to start. Search the forum for what to unplug there are post with pictures of it.

well i have aftermarket unit that has bluetooth my stock i dont think it came wit the bluetooth

[Fifty150hs]

Originally Posted by cuban_bmwx5

well i have aftermarket unit that has bluetooth my stock i dont think it came wit the bluetooth

Check and make sue you don't.

[cuban_bmwx5]

Originally Posted by Fifty150hs

Check and make sue you don't.

i am gonna have to check the original deck and see if it has bluetooth

[cuban_bmwx5]

Originally Posted by Crowz

There are soooo many things in an e53 that can kill the battery. Mine was the Bluetooth module (tcu). Unplugging it is a simple test to see if that's the issue on it but again there are tons of possibilities.

But if you have the Bluetooth unit its a good a place as any to start. Search the forum for what to unplug there are post with pictures of it.

well i have aftermarket unit that has bluetooth my stock i dont think it came wit the bluetooth