2000 Volvo VNL 770 AC Problem please help!

Here is my problem I bought a brand new ac compressor 6 months ago, last month the ac stop cooling for time to time and i mean that it was cooling today perfect and tomorrow blows hot air.

The mechanic told me the compressor kicks in works fine that the problem was the AC control module that is not starting kicking the compressor and also not stopping the fan it stay all day on with the compressor off, i replaced that module from the volvo dealer and the truck still doing the same thing once the compressor kicks in it will cool the air like it should be.

Anyone knows why is this happening or what is not letting turn on the compressor when i put the ac in the cabin?

I appreciate the help in advance!

 

The old one was blinking slow green witch means good I bought the new one and is working good too, i will check the wires from the compressor.

Thanks!

 

It have to be electrical but where is what i want to know lol

 

Thanks i will look into that, let me ask you something...

The fan of my truck should not stay on all the time right? I mean if the temp is normal there is no reason to stay on right? Because when the fan stay on all the time the compressor doesn’t kick in so it won’t blow cold air have you seen anything like this?

 

Actively engaged