Jerry, the outside fan for the fridge only comes on when the temperature of the "evaporator?" (I'm never sure what that part of the system is called - but it's a heat ex-changer that transfers heat inside the refrigerator to the outside) gets above a certain level - my fuzzy memory seems to recall 110 degrees. Whatever - it will not run all night but helps to improve the system's performance if it is having to deal with a lot of heat.
I don't recall what the Amp draw of the OEM fan is, I replaced mine with two PC fans that draw less current, are quieter and move more air. I seem to think it was on the order of 1 Amp, but, as I said, it does not run continuously. I think if you take the outside vent screen off (lots of screws), you can get to the fan and its Amp rating is shown on it, if you're really concerned.
Hi-Lo 1707T - Tire Minder TPMS on Tow Vehicle and Trailer, 300W Solar Battery Charger, Equal-i-zer WDH
2014 F150 Platinum 4x4 3.5L EcoBoost SCrew