blackshaw

2002 e320 AC stopped blowing cold / blower motor fan speeds are all over the place or dont come on at all as well. I changed the expansion valve to see if it would help with the over pressured system...but it did not. I t will pressure up and hold pressure so I am not sure if it has a leak but i am guessing not. I think the compressor is bad or the clutch maybe. I tried charging it with freon and got it to take some and clutch to kick on once for a moment finally but it just pressured up quickly and clutch wouldn't come on anymore.. Has anyone else had any experiance with this issue.. by the way my carsoft scan shows P20ce for the high coolant pressure DTC... any suggestions or help would be great!! I am thinking of checking the duovalve isnt stuck closed or something next before buying compressor.

machadosl

It seems more that you will need to replace the compressor clutch.
If you replaced the expansion valve and has not seen the oil with a grey color it is a good sign that the problem is not with the HVAC compressor.
The high pressure of coolant probably was promoted by you when you overfilled the system. To fill up the system correctly you need a manifold to see the pressure in the low and the hi side at the same time and also, you need that your compressor is engaging.

kajtek1

High coolant pressure has nothing to do with AC.
Not sure how you get the code, as I don't know cooling system has pressure sensor, but if that is so - get new coolant cap

machadosl

Katjek, I was referring to the coolant of the HVAC not the engine coolant.