this is a common fault with these fridge freezers. its often connected with the defrost sensors in the back of the unit. if the sensor goes down then the fridge doesnt defrost and subsequently ices up and this eventually stops the fan in the back from spinning. theres much more info as well as links to parts suppliers over on the uk white goods forum(yes, such a place does exist, good old internet eh!!) i fixed mine which had a fault on the fridge side, and it cost me only about 20 quid for the part which just needed plugging in.
johnr, March 2008