samsung rs21dcns fridge evap frozen

hi guys another famous samsung prob , had this the other day i couldnt see any error on the display customer sayes fan is noisy fridge side and no water , i reset the water filter light and the water worked straight away , i checked the d/f heater checked out ok , gutter heater no resistance so i checked the d/f sensor no resistance . i tried forced defrost and self test but i have the samsung manual and the written english is poor to say the least hard to read it can someone give me the steps for forced defrost . i also disconnected the main control board and checked the connections for resistance as per the manual , i couldnt get any values for anything in the fridge side , but i can get 220v from the block connectors on the back wall of the fridge ! i replaced the d/f sensor as it seems its the most likely to go , customer rang to say that it didnt work and its just as bad , some self test steps for this m/c also please thanks