I don't know if the dealer did, but my buddy said he cleaned all the connectors and checked the pins. I doubt he check the length of wire for a break somewhere.
I found this thread that matches his symptoms almost exactly. The end result for that one is the cam gear and dizzy gear were worn enough that there was too much slop when cold and it set the light off, once it warmed up an the metal expanded, the problem went away.
https://www.jeepforum.com/forum/f9/2...topics/3537194