If the compressor and condensor fan is off, then your refer is most likely either stuck in a defrost cycle, or the cold control has failed. Open the refer door and tap the cold control to see if the contacts close. If it starts working then you need a cold control. If not, just behind the control is an opening that you can insert a screwdriver into. This is the defrost timer and it may have gone into defrost, but didn't make it back out. Try to turn the timer and see if the refer comes back to life. If it does, then it's probably time for a defrost timer.