Hi all and a happy new year !!

i have just purchased my first x type 2001 2.5 v6 sport ...... the car has sat nav / tv etc the problem i have is none on the fan system in the car works at all , no heater no heated screen no climate / air con all other electrics work fine (when climate is pressed it displays communication fault contact dealer), i have spoken to jag and they suggest a wiring fault and would like £99.95 + vat to have a look . i was wondering if this is a common fault or if anyone has any ideas i have a fairly good vehicle knowledge so am not affraid on having a go . thanks in advance Gavin