Remove the access panel and check the electrical connections. When you say it turns on then off, I assume you are referring to the compressor runs then stops. When it does stop, do you hear an audible click from the compressor? Is the cavity cold at all? You may have a problem with the cold control (AP2113750) short cycling the compressor, or it may be the compressor starter (AP2113676) that has failed or even the compressor itself. You will want to do some checks with a multimeter before going to far.