hi. i have had the same problem with this fridge.
its the plastic elbow at the top of the freezer at the back which supplies the ice maker with water.
this has a heater element arount it thats ment to stop water freezing in it but it still freezes . you need to take out the ice bucket and the ice tray at the top then pull off the silicone tube inside then some how apply heat to the elbow that goes out to the back of the freezer. Job done.
you will probably find the water pipe has blown off the back of the fridge because of this
tipps, February 2013