thanks Paul.This all leads me to think this is a mechanical problem and thus not too difficult to fix.
Shame it wasn't corrected at the outset or by a recall,heated seats are not rocket science, never had any problems with those on my 12 year old Volvo.
I expect the bean counters said no,let the dealers fix it under warranty.
The irony is that I never use them but the 'boss' uses them all the time in winter so it becomes an essential extra on any car.
P