It seems my A/C isn't blowing cold air all the time. It's as if the compressor isn't kicking on or is intermittent. It eventually does, but it takes a long time to cool the vehicle. I've had it about 6 years and it has definitely changed. Vehicle is an '04 with 106K now.

 

Can you hear your compressor turn on and off? Mine compressor didn't turn on at all when I bought the truck because It was out of freon. Paid $90 to charge it and now it works great.

 

I haven't gotten out of the vehicle to listen. My understanding is the A/C system is closed, meaning the only way it can be low is due to a leak somewhere. I have a local auto A/C place I've used in the past but it has changed hands. Just trying to get an idea of what it may be. I'm thinking the system thermostat but I really don't know enough about it.

 

ALL ac systems are closed. Over time a very small; leak can reduce your Freon enough to prevent the compressor turning on. You could try charging it and take your chances

 

Mine did the same thing, it started blowing warm on one side of the car.

I took it to a Lexus dealer, he said it was probably low on refrigerant. They checked it out and couldn't find the leak, they said it was likely somewhere in the rear evaporator in the rear seating area and it's not worth addressing because you'd be looking at something north of a thousand dollars to dig it out. You're better off just topping off as needed. So I let them charge the system.

It lasted about 2 years and started creeping up again. This time, I did it myself with about a $6 can of R-134 instead of paying a dealer a few hundred.

I think it's a pretty widespread issue. If you do it yourself, I would recommend using R-134 without any sealers and make sure you don't overcharge. There's online charts so you know what pressure should be at what temperature. It's better to go a little lower than and see how it does. I'd recommend at the least a thermometer probe to check vent temps (like $5 at Harbor Freight) and a low side pressure hose with gauge.

Technically, the proper way to charge these systems is not by reading pressures but charging it by weight, but in my experience you can get close enough to where you have ice cold air just topping off as needed. Just do a little research to make sure you don't do something dumb or just take it to a shop.

 

Quick update.

I took the GX to a local auto A/C shop yesterday. They said everything seemed to be working fine. Recharged the system and added dye. Suggested I bring it back next week so they could shine a light on it to see if they can find a leak. $95. A/C is blowing cold. I'll go by next week to see if they find a leak.

 

My 2006 GX's A/C just started blowing warm air today. Last summer the rear A/C was very slow to cool, but would eventually become tolerable, not sure if that has anything to do with this.

I was able to run the A/C self diagnosis test:

https://www.clublexus.com/forums/per...eed-codes.html

I got code: 00

I'm not sure what to do. The compressor is running. When on, it cools the air very slightly. When I turn it off I can feel the cold air turn off. My guess is the refrigerant is low. Any guesses, suggestions?

Thanks.

 

I brought the truck in yesterday. The A/C system was almost completely empty. They did an evacuation and full recharge. I'm blowing cold again, but keeping an eye on everything. I'll update if I find a problem.