When driving my Range Rover Sport 2010 the kupe fan, the LCD display and the rpm and speedometer went black at the same time. I went to a friend with a diagnose tool and when downloading the data the fan and displays started to working. Immediately when disconnecting the tool the items went back to not functioning.
Any idea?

 

Thanks for the tip. I will pass it on to the mechanic. They seems a bit clueless so far.