The leak could be from inside the freezer section, fresh food section or the water supply line to the ice maker. Pull the refrigerator away from the wall, disconnect the power cord and remove the lower barrier. Check the defrost drain pan and the drain loop for any signs of a water leak. If the drain pan is dry of water, the source of the leak is likely a blockage in the defrost drain trough located behind the rear panel inside the freezer section. Disconnect the power cord and remove the air tower (key#1) and the evaporator cover (key#2). Check for an ice blockage in the center area of the defrost drain trough (key#4).
NOTE: Be careful around the evaporator coils (key#14), the fins are razor sharp
. Also if you have an ice maker, check the ice maker fill tube (key#18) to see if it has worked itself loose.