2001 Honda Civic Air Conditioning shuts off when hot

My Honda's air conditioning has started to work intermittently. When the car is cold (relatively speaking) the A/C starts immediately and blows very cold air. The compressor clutch and condenser fan both work. The problem occurs when driving: the A/C will work fine for 3-5 minutes and then stop altogether. When I pull over and check under the hood I find the condenser fan is running but the compressor is no longer spinning. The light on the dash button never goes out unless you switch the system off. If the A/C is turned off for 10 minutes or so, and then turned back on again it blows cold for another 3-6 minutes and then fails again.
Seeing as it blows very cold when it does work I assume the refrigerant charge is sufficient. The relays and fuses all test good (when cold). According to my Haynes manual the Low/High pressure switch on the Receiver/Dryer is normally closed. Unplugging the connector at the switch causes BOTH the compressor and fan to shut off, not just the compressor as in my case. The wiring diagram I have shows a possible thermal cutout on the compressor, but I cannot tell if there is one without removing a couple other accessories. I'm afraid that EITHER the compressor is overheating and the thermal cutout is disengaging the clutch (and then allows the system to work again once it has cooled) OR the electronics that control the system are getting hot and failing. Whatcya think?