Originally Posted by clarklaflare
.... How many batteries is it going to take before your dealer and FCA get together and find the real problem? ...
I'm guessing 2. Sounds like the dealer is working on figuring out the problem now. Why else would they need to keep the Jeep over night. Simply testing a battery doesn't take that long, so it sounds like they're also testing for the underlying power drain.
This may be completely random, but have you checked to confirm all your interior lights turn on/off. It's possible one is left on and you don't see it because they bulb has failed. Even without producing light, if it's "on", it will be drawing power, and a single interior light will take a while to drain a battery due to the low draw.
Another issue I've seen with older trucks (but could happen on a 2 year old Jeep) is the hitch wiring. If the plug is corroded, has a short, or something similar it could be drawing power constantly. Make sure the hitch plug (assuming you have one) is clean and the terminals aren't bridged.
Anyway, I suspect the dealer will find the source soon. At least that's why I assume they wanted to keep it over night, so they can test for it.