I searched the forum, but couldn't find any answer to my problem. My '00 Explorer Sport has no A/C. I looked in the engine compartment, and the clutch isn't engaging. Checked fuses, and even swapped the relay w/ another. I tried jumpering the pressure switch with a paperclip too. No luck. When I press the valve on the service port, I hear a strong hiss - which tells me there's pressure, and probably no leaks. Any other ideas??? It's finally starting to get warm, and you can only drive with the sunroof open for so long. Once it starts hitting in the 70's, I'll NEED to use the A/C (black truck, go figure?).