So with your 97 Landcruiser, did you ever get the problem fix? I brought it to Lexus dealer; they tried their best, but could not duplicate the problem. It seems to happen only on very hot day and while driving.
For testing purpose, I plan to remove temporarily the coolant temperature sensor when the AC cuts out. I don't know if the switch is bad or the AC is so sensitive to a little heat increase.
That's interesting. My car has big Hella lights mounted in front of the grill! It did have overheat problem, but we replaced the thermostat and flush cooling the system.
Most of the time, the temperature is just a little below the middle of the scale. I learned that in the 470 series, they put in electric AC fan.
Your information is very useful. Thanks.