If your fan motor is not running either, you have a power problem.
The defrost timer is under the rear of the refrigerator near the compressor.
This timer may be stuck in the defrost mode and not sending power to the compressor and fan motor.
Locate the timer and turn it clockwise. If the compressor and fan come on,replace the defrost timer.
If you turn it and they do not come on,check power to and thru the cold control thermostat in the fresh food section.