Frigidaire Ice Maker not working

Hello, My girlfriend has a Frigidaire Refrigerator that is not making ice. When I put the 'bar' in the ice making position, i can hear the ice maker 'call' for water, but cubes are never made. Could it be the water line is frozen in the freezer? how can I check/repair this situation if this is the problem. any help is would be great!
Thanks
Bob