G'day I just thought I would share, I had a friend of mine hook up his professional scanner, sorry I can not remember the brand, to my 2005 WJ 2.7 CRD on Saturday and he was having trouble getting it to communicate. He had put in the vehicle make as Jeep, but when he changed the make to Chrysler he was able to read and clear the fault codes in the car.
So if you are having trouble it might be worth putting Chrysler into your scanner for the make.
Cheers Andrew