We have just gone through the same thing with our X5 (amongst other issues). Last week it totally died and we had to get BMW assist to get us going. Took it straight to the dealer who were great.

Our problem is (and I went through this with my 5 series) is that we live too close to our place of work, and apparently with all the on board systems in the new X5, the alternator is only giving a trickle charge to the battery of approx 10% of its output.

It is not being driven long enough on each journey so we have been steadily draining the battery. A software update has apparently changed this to a little more back to the battery, but it seems that all those systems come at a cost for us short trippers.

I suggested we put in a heavier battery but the dealership first wanted to go through a process (as the computer told them we were short tripping) of a battery re-charge then see how we go.

They have also suggested that I get a battery charger and use it once a month or so, and monitor the battery.

Bit rich considering I have paid over $160k for the thing.....

And just to top it off... my 5 series died the other day and is now going in for a battery check.

I am now in the process of investigating the viability of an aftermarket/OEM alternator change. I figure there are vehicles in the BMW range that have a higher draw than mine (eg security series) It might be a wild goose chase but I can't keep calling BMW assist....

Cheers

J

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