Ge refrigerator had ice build up and was not cooling properly moved all food made sure none was against back wall and reset but now the fan or nothing is running at all

First check the defrost timer. It will turn off compressor and if motor goes out on timer it won't come back on. As for the rest of the unit you will need a volt/ohm meter to check it out. Here is a booklet: https://dl.dropbox.com/u/8010163/How%20to%20use%20Test%20Equipment%20Service%20Manu al.pdf
Make sure the plug that goes to refrigerator has power to it.