I have just bought this 2008 xf and it has 2 faults. One was a leak, diagnosed to a split seam on the thermostat housing, the other I cannot fathom.
The Sat nav doesn't work, and the radio is dead. The screen however shows lines and lines of weird stuff.



Anybody know what is wrong and how to fix it ?

 

Check under the passenger seat for signs of corrosion, there are modules on the floor under the seat

 

Thanks for the info John. I lifted the carpet and examined the electrics. Everything was dry and completely rust ? water free. I tried testing the box of tricks using a MOST Fiber Optic Loop Cable Plug Connector also tried it on the DVD player in the boot (trunk) Neither tests shoed anything. It's not as if I have a blank screen, what my photo shows is always there.