2004 Lexus 330RX Air Conditioning Problem

I've had mine since the 4th of July but I haven't taken any long trips. No A/C problems. FWIW, these days almost everything is run by computers and can sometimes be fixed by a "reboot". About 10 years ago I had a Pontiac Firebird and we were driving around Las Vegas looking at homes in 100 degree+ weather. After looking at one house we got back in the car and the A/C wouldn't work. HELP!!!!!! Experimenting, I shut down the car and restarted it. Everything worked fine and I never again had that problem.

My 2002 Camry LE V6 had an issue with its AC that after a 5 hour long trip on a humid, hot day (over 90 degrees), the A/C froze up and the air flow stopped. I took a 45 min break for lunch and came back and found a puddle of water with chunks of ice in it. I presented this problem to my local dealer and they checked the drain pipe and it was not faulty or plugged. They said the humidity caused this to happen, and suggested I use the re-circulate button instead of sucking in fresh humid air. I have followed their suggestions and I have not had any issue after that.

Their logic makes sense, yet, I have never had any vehicle in the last 25 years who's A/C has frozen up like this. Perhaps the gas is overfilled?

Yes, my previous car (not a Toyota) had the same problem. The A/C was ice cold even on 95-degree day. After a few hours the condenser would be frozen solid with ice and no air came out. Turned out the compressor was way too efficient. The solution was to turn off the A/C and leave the fan on about once every hour or so.

Did it stop blowing air altogether or was air blowing but just not cold air? If no air was flowing, I bet the evaporator was iced... not uncommon when you're running the AC full on a humid day. If that was the case, use the recirculate button to keep the humidity of the air flowing through the evaporator lower.

It sounds like a memory conflict. Update the drivers off of the Lexus web site. :-), and defrag the hard disk.

I first encountered this particular problem in mid 1993 in a new 1992 LS400. Traveling from Lewistown MT as we climbed toward the continental divide west of Helena. Absolutely no air flow from the system about halfway up. Turned the system off, lowered the windows, etc, etc. Shortly after reaching the top it worked again.

Last year, summer, I heard of a report of another 92 coming north out of Fresno over the siskayos, apparently the same thing happened.

I would have thought Lexus would have it fixed by now. Seemed to have something to do with high elevations and high OAT.

Knowing a great deal about the Lexus climate control system (temperature sensor. thermistor, attached directly to the downstream side of the A/C evaporator) it's hard to understand how this could happen.

Some cars cut the air conditioning out when the engine is under sustained high load conditions. The idea is to spare the engine extra work and to avoid over heating. maybe the Lexus system does this deliberately?

Yes, Lexus will stop teh A/C compressor from operating if the engine begins to overheat. I am quite certain that was not the problem in 93. Besides which we could get no airflow at all from the system and that, would only be the result of a frozen over A/C evaporator.