Sounds like exaclty the same fault on my 2013 XF Sport.
Makes a hideous screeching sound when I start the car then says 'camera not available, contact dealer'
It happened a couple of months ago so I booked it into the local dealership, but before the appoinment came around it started working again, so I cancelled the booking. since then it's happening again so I've re-booked it for a few weeks time.
They tell emt the diagnostic charges are £180 per hour - so if I can help them to find the failt in a bout 5 minutes it's be a huge help!
Do you know what the part number / description is? And can I buy it from the main dealer myself?
I've looked t the rubber hose between the boot lid & body - all looks fine but obviously can;lt see what's going on insite the tube.
Thanks in advance