2004 RX330, air conditioning and heater both work fine. But oddly, when I push the air recirculating button, I hear noises in the dash. Clicking and slight chirping sounds. Sounds like something is moving in the ductwork. When I turn off recirculating, sound goes away.
Any thoughts????

 

May sound stupid, but have you checked the cabin air filter? I had a similar thing with a car years ago, which was unavoidably parked under trees at work. Turned out there were a heap of leaves in it, and it only rustled when on recirc. 😒

 

Thanks Bluerobotz. I’ve been meaning to change the cabin filter.
I hope that fixes it, but the clicking/chirping sound comes from behind the instrument panel as well as above the glovebox, so I’m skeptical. Unless leaves have made their way all up in there.
Sounds more like a mechanical clicking than rustling.

 

My guess is that the servo that operates the recirculating damper is failing, causing it to hunt for its position. I currently have a similar problem with my mode servo and I'm not looking forward to replacing it. The blend servos to control the temperature for the driver and passenger are fairly accessible. The mode servo is pretty high up on the driver side. I haven't hunted down the recirculating/fresh air servo since mine is not making noise. Search around for Lexus A/C servo and you'll see that you have plenty of company with this issue.

 

Thank you bj.
i will look into that