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2002 nissan xterra, new compressor, new thermal control amplifier. The compressor works but the clutch wont engage unless hard wired to battery or i squeeze the magnet in the relay. I tryed switching the horn relay to see if it was out and it didnt work. Any help please i have a 10 month old baby to drive around in this texas heat!
@texasheat as @jimfixer already suggested, one of the main causes for that can be a low level refrigerant. there are also a few more things that you could check. Problems like these are hard to troubleshoot. You can test the AC relay properly by following the procedures outlined in the manual. After the relay you only have some thermal protection before the compressor. Start off with the “Nissan trouble Diagnoses” and see where it takes you:
For more of the way your AC works and complete wiring diagram and diagnostics etc. use this part of the manual XTerra Heater Air Conditioner
Odds are the compressor is not engaging without being hot wired is from lack of Freon. You can do damage to the system if you run it this way . Make sure the system is fully charged and check it for leaks . Hope this helps
