> get a battery and Battery Tender yourself, ~$200.


Well, that certainly will treat the symptom. But I find it hilarious that a $70,000 vehicle must be kept on a battery charger if it isn't run 800 miles a month!

Here's what they SHOULD do, but likely did not do because it takes some time.

(1) with a good, charged-up battery, disconnect it at the battery terminal and put an accurate digital ammeter between the positive terminal and the positive battery clamp.

(2) close the doors, remove the key, and seal-it up as if it was parked for the night.

(3) Read the current drain, which will be too high since the car has not yet gone "too sleep."

(4) Leave it long enough to go to sleep/inactive mode and read the current drain. On my Z4 it takes about 20-30 minutes to go to sleep.

(5) Compare the current drain in sleep mode with the range BMW specifies for the vehicle.

The acceptable drain varies by vehicle, but for my Z4 I believe it was 20-40 milliamp, and my reading was 24 milliamp.

40 milliamp would be about 1 amp-hr per day/24 hr period. So with an 80 amp-hr battery, just sitting there it would drain the battery a bit more than 1% a day.


P.S.

I do not know about the X5, but my Z4 has a "park on the side of the road" "feature" called "standing lamps" which allows one to put either the left or the right turn signal lamps on solid while parked:

Left or right standing lamps*

As an additional feature, you can illuminate
your vehicle on either side for parking:

1. Turn the ignition key to position 0 or
remove it

2. Turn off the low beams

3. Push the lever in the appropriate turnsignal
direction. The lever engages in
the turn signal position.


It would seem that one could accidentally activate this "feature" if they bumped the turn signal stalk prior to leaving the car. I wonder if this is a possible explanation.