Hey everyone. I have a 2014 RX350. On Tuesday we had strange weather (Virginia) and I ended up turning on my heater on the way home (cold and rainy). Parked it while heater was running. Went to drive today (Thursday) and it's 90 degrees again. Turning down the temp doesn't do anything and it just blows hot air. I cycled thru all temp settings and turned on/off. Fuses all look OK. I'm going to pick up a pressure gauge tomorrow to check pressures.

Any ideas considering I switched it to heat this week? I didn't turn the AC off when running the heat so I'm wondering if there is some electronic control that's stuck.

Thanks!

 

Could be that the vent blend doors controlled by the servo motors behind the vents are stuck. Could also be a stuck or failed valve. Do you hear your compressor turning on or off when you activate your A/C?

 

Thank you for the suggestions. I double checked the fuses - they are okay.

I do not hear the compressor turning on, and the low pressure port reads in the red which suggests the compressor is not turning on. I read about the magnet trick on the 2010-11 RX350s, but I can't find anything that suggests it would work on a 3rd Gen. Maybe I'll give it a try this afternoon. Unfortunately for me, there doesn't seem to be a lot of AC issues for the 3rd Gens (good for all). I'll continue to hunt for instructions on how to further diagnose.

Thanks again

 

I think the magnet trick should be your next step. Let us know if that resolves your issue.

 

The magnet trick worked - just wanted to follow up in case anyone else has the issue on the third gens. It took me a bit to figure out the orientation. The sensor where the magnet goes is facing up toward the top of the engine bay. I accessed it from under the car and reached up on top of the sensor without being able to see it. Hope this helps someone else.

Thanks everyone!

 

Well done. Where did you obtain your magnet, and what size magnet did you use?

 

The magnet came from the side of the refrigerator. I think it is part of a broken refrigerator magnet so I know that's not helpful. It's smaller than a dime, it's chrome colored, and it's very very strong.

I'm trying to upload a pic in case it helps. Take the skirt off the bottom of the car, and you're looking up at the bottom of the compressor. The red arrow shows where you put the magnet. Up just over the connector, and it sticks.

Thanks again everyone!

 

Thanks for the details. This is one very valuable trick that all of us 3rd generation RX owners need to keep in mind.