My boyfriend was the service mgr. at Chrysler for 5 years...he said that this is a common problem with the Xfires. My roadster is doing the same thing, but only some of the time. It seems like cold weather worsens the problem, but if I hold down the brake pedal long enough, most of them seem to turn themselves back on. It's almost like some of the LED's are "lazy" and take a while to warm up, if they do at all.

So you're not alone! I'm going to be replacing mine in the next month or so...It looks horrible from behind when only some of the LED's work.