Hi Guys
I have a 2005 XK8 S, with the same 0.5mtr range with the fob, did all the usual new car battery-NO, had both fobs repaired with new buttons, plus new batteries-NO, checked the coaxial connections to the rear screen, all ok,


so took out the locking module ( Made by FORD by the way) and removed the two pcb's. then sucked off the old solder, so desoldering the three connections on both boards, re-soldered the connections (very fiddly, but with a magnifying head band, and a very fine pcb soldering iron)......re-installed and it made no difference whatsoever.
So perhaps its the board, who knows, and a fee of £195 to repair seems a little excessive, so I've lived with it for ten years, so looks like I'll just carry on with very little range. That's Jaguar for you, but I still luv the car with all its idiosyncrasies. If anybody comes up with any other fixes I'd like to know