here is a new recaro heated seat element with airbag sensor mat and foam padding assembly,it also contains the heating thermostat for all the 5 heating elements in the seat, normally £300 only £100. I know because my heated drivers seat went cold this winter. disassembly is not easy. from germany ebay
http://cgi.ebay.de/Audi-A8-4D-S8-Rec...item58885ec361