O.K. sorry to keep banging on about this but had an X range rover mech do a code read on my Rangy and he said the head unit is duff or needs a software update, now the car is 10 years old how come it suddenly needs a software update what has changed that it now needs this? so should I take it to the main stealers for another dignosis and let them replace the head unit with a new one (cost of unit plus fitting plus codingplus diagnostics ) or do i go down the route of buying a recon unit fit it myself and buy an Autel Elite DiagLink OBD2 Diagnostic Scanner and code it myself ? your thoughts on this guys what would you do? advise?

TIA Mark.