You can test the A/C clutch by putting 12v directly to the clutch. Open the Large black plastic box that houses the RCM, BCM and ECU, on the front wall of that box is a connector that the control module inside the car connects to the clutch. Disconnect the two halves of that connector and jump a wire direct from the positive pole of the battery to the A/C clutch. I have done this, but I have forgotten the colors of the wire. You can hear the clutch engage if it is working properly. This test bypasses all the sensors, so you can tell if your clutch is bad or something within the system is causing the A/C compress to fail to run. You can find all the pertinent info in the service manual beginning at in section 24 page 49.