X5 Completely Dead, Won't Start

[Xydin]

It sounds like the battery to me, but some other possibilities would be the anti-theft system immobilizing the vehicle, or an issue with the instrument cluster. Maybe try to push around on the instrument cluster a bit when you go to start it in case there is a loose connection? I had a friend who had a similar issue; he had to give his instrument cluster a good whack to get his car started every now and then (I would not recommend this, he eventually cracked his dash lol). When he finally got it replaced, the problem was solved.

Do you have any reader to check for fault codes?

[nikolai]

Thank you, I will try those suggestions. I am at Napa now getting the battery back up to full charge - it was at 12.1V. Apparently it checks out as good, so just making sure it's fully charged now.

I didn't try my code reader as I assumed it wouldn't work due to nothing else electrical showing any signs of life in the car. I'll try that once back home. Thank you.

[nikolai]

I ended up getting a brand new battery....I popped it in and it started right up. Now I have to determine what (if anything) caused the battery to die. I know there are multiple other threads on this, and I will likely start with the Final Stage Resistor. Thank you for the help.