I'm willing to bet that its the connection of the battery, make sure there isnt any acid around the battery's connections and then clean it off with luke warm water if there is.

Otherwise it sounds like your alternator is NG.

The park indicator light is supposed to stay on in BMW's. Thats 100% normal. If you're battery connections are clean and tightened in all the way, I'm willing to bet it is the alternator. Not an uncommon failure on an X5 of your age.

Well it looks like it was a bad battery. Started 3 days in a row at -35C in a row. Thanks for the advice. Hope like like Al Gores global warning kicks in soon.:bustingup In are neck of the woods oil pan heater is a must.

Dead battery is back. Pulled fuse 74 and dead after two weeks of working just fine. What is up with this?