mine did this too on sunday!!! 32 degrees F it was only after about 3 hours of being parked. in the snow (first trip to the snow). EXACT SAME SYMPTOMS. I was worried I left the hatch open or something.

The strange thing is 12 hours later when i started it in the morning (still 32 degrees and probably colder throughout the night) it cranked like new. Battery is less than a year old.

keep us posted!

FYI 06 4.8IS

Tahoe? I was up in dorrington (HWY 4) and bear valley. The X5 was AMAZING in the blizzard!