Hello, my AC stopped working, just blows ambient air. Last year I replaced the variable displacement valve in the compressor, drier desiccant element, evacuated the system and recharged to factory amount. It always took 10-15 minutes to start blowing cold, even after I replaced the compressor valve. The clutch always engaged right away, but now the clutch doesn't engage at all. The system has pressure, 130 psi on both high and low sides (equalized pressure since the clutch isn't on and compressor isn't compressing). I can rotate the compressor by hand with no binding, seems like it should do something if the clutch would engage). My guess is something to do with control or a bad clutch coil. The 2005 X5 4.4L only has one fan, no auxiliary fan in front of radiator/condenser assembly, and it comes on when engine is hot, but the fan doesn't come on when the engine is cold and AC is on.
Could someone please tell me how to test the fan controls, and explain how it should operate as related to the AC system?
Also, where is the low pressure switch? I see the high pressure switch, but don't see any switches on the low side under the hood. Could it be under the dash near the evap core and expansion valve?
In general, how do I check the fan controls, and high & low pressure switches. Pretty sure I know how the check the clutch coil and need to do that first. Also, I checked the fuses and all are good.
Thank you!