Refrigerator freezer not making cold

Well its been exactly 5 years and our GE refrigerator stopped working. **The temps are now 68 and 50. **It the fan is running so it must be either the start relay or the motherboard. ** Where and how do I check these? **Could it just be dirty and need to be cleaned? ****I took the back off and I believe the condenser is running. **It is vibrating and warm to the touch. **I am at a loss of what to do.

Since there are 3 pins. Where do I check the voltage at the compressor?

I checked the resistance of the compressor .010/.003/.012 ohms. Shouldn’t 2 of the readings be lower than the third?

I also checked the PTC, no rattle or burnt smell, resistance across the terminals was 1.15 ohms.

Evaporator fan is running but the evaporator is not cold.