Fan not working ?

Refrigerator & Freezer Repair
1

I assume the problem started a few days ago.The ice maker would have big chunks of halph frozen ice in it causing the machine to make loud noises when dispensing ice. Woke up this morning with temperatures reading 54 in fridge and 15 in freezer. The ice had melted out of the ice bin and was dripping into freezer. Its funny because the water dripping in freezer had began to make icicles on racks. I noticed that the whole back of freezer was frozen solid with ice. I first thought bad defrost timer than i realized it doesn’t have one. I have defrosted the evap and checked the drain line"it was clean no obstruction" I now am wondering if the fan in the refrigerator is bad its not on and even if I turn on the turbo cool it doesn’t run.I am not sure how or when the fan operates any help would be appreciative Thanks