I have a 2008 Lexus SC430, only has 40k miles and is in excellent condition. Recently A/C stopped blowing cold suddenly, one day it was working great, the next day it was blowing warn. Compressor still kicks on and there are no visible leaks in the system. I worked as a mechanic for several years but not much A/C experience. Any experienced people here with suggestions? TIA

 

When the compressor is kicked on, do the lines under the hood get cold?

Trying to figure out if it is the compressor or a blend door issue

Do you have any other symptoms?

 

I had the same issue on my 2004 last month. One day the ac was working fine and the next day it started blowing warm/hot air. I took it to a Toyota dealership and they did a diagnostic. They told me that a temperature sensor was bad. They didn’t tell me which one or give me a part number and told me to take it to a Lexus dealer. I did further research and found out the in cabin temperature sensor that is located under the steering wheel next to your right knee was probably the problem. Said to remove it and clean it well with electronic cleaner. If that didn’t resolve the issue, a new cabin temperature sensor was most likely needed. I bought a can of CRC electronic cleaner and cleaned the sensor really well and then let it dry in the sun for 15 minutes. Reinstalled it back in the car and HVAC is working perfectly.

 

No, which seems to indicate a bad compressor. The thing that kind of doesn't make sense to me is that the compressor is still kicking on and running.

 

Lines do not get cold, which seems to indicate a bad compressor. The thing that kind of doesn't make sense to me is that the compressor is still kicking on and running. No other symptoms.

 

Thanks for responding. Had no idea about this and no one had mentioned this before now. I will give it a try!

 

I had the same problem. I first checked the Freon and all was well.
I took it to the Toyota dealer expecting to have a horrendous bill. They removed the Freon, cleaned it, and put it back in. Its been running fine for the two years since! $250!

 

If you go to a national auto parts store like O'reilley's you can rent a set of AC Gauges for free. You can check the pressures in your car. However, you said that the clutch is engaging, which leads me to think the pressures must be high enough.

I am at a loss, might be time to seek professional help