New poster here. Not a mechanic. I learn from youtube but cannot figure this out. I have a 2018 Explorer XLT, 3.5L. Front and rear a/c system. My freon has been checked and is full with no leaks anywhere. My compressor turns on, fuses and all have been checked. One day I will get in and turn on the a/c and it is good and cool. Next day it blows 75 degrees out of the vents. When it is cool the compressor kicks on and off as normal. When it blows 75, the compressor kicks on and just stays on and never shuts off. I was told to check the pressure switch but read in a different forum that this year model doesnt have that anymore. Can anyone make any suggestions on what to look for next???

 

Just about all have a hi press and lo press cut off switches. Excessive hi press can blow open the condenser, while low pressure can destroy the compressor because the refrigerant oil lubricates the compressor. Some sw are mounted on the lines , some on components, rest assured they are there.

If either one is open system will not work at all..
Ambient temp can have an effect on why and when this is happening. So can a low refrigerant charge or contaminates in the system.
I would be very careful with some videos. Some are OK and some not accurate.