Here’s where it gets nerdy. Most mini fridges have an evaporator fan inside the freezer section. This fan pushes cold air from the freezer into the main compartment. Open the freezer door (if you have one) and see if the fan is spinning.
If it’s not spinning, it’s likely seized up or dead. You can sometimes give it a gentle spin with a pen to see if it kicks on, but more often than not, you’ll need a replacement fan. Budget about $15 and the patience of a saint to install it.
Refrigerator not cooling. : r/Repairs
Another culprit: the startup relay or capacitor. This little plastic box on the compressor (the black round thing at the bottom) gives the compressor a jolt of power to get going. If it’s fried, the compressor just sits there, silent and moody.
Replacing a relay is cheap—like, $8 cheap. Unplug the fridge, pop off the access panel (usually held by one screw), and remove the relay. If it looks charred or you hear it rattle when you shake it, that’s your problem. Order a new one, swap it out, and you’re a hero.
