Touch screen has died. Just flashes up "Jaguar". Rebooted. No good. What is likely to be the problem?

 

The battery is not putting out full voltage. And the forum you want is one of the two XF forums (fora?) - this forum is for the XK

 

I think he meant "this forum is for the XK". More specifically, the X150 bodied 2007-2015 XK/XKR.
I do agree however, it is probably your battery is a bit low. Charge it up with an actual charger for a day or so, not a trickle/maintainer style. If that fails, have a load test performed on your battery, it may be on its way out.

 

The XF is at least as touchy if not more so than the XK. With your issues the first port of call is always the battery.

 

Of course I did mean the XK - I blame my fuzziness on the fact that I am still working on my first cup of coffee...but I stand by the opinion that the battery is the first port of call for this sort of symptom.