The pipe normally only gets ice when poor air flow from within the fridge compartment is fialing to keep the pipe warm ( as in above freezing ) Check the vents in the fridge are free from food items, jars positioned too close etc Is the water dispenser working? Is there a coil of pipe behind the lower salad tray in the fridge and has this frozen too?
Also the manuf will instruct a 24 hour switch off as a cure, this often works when combined with unblockingt he air vents.
terryT, December 2008