2018 TLX - Hello everybody I searched the forum and couldn’t find any thread concerning this clicking noise. With my AC on, there is a continuous clicking coming from under the dash gauges area and it seems like it might be from the firewall. It sounds like a relay of sorts that continuously clicks only when the compressor is on. I live in Florida so I never use my heat as I’ve read this might be a problem with some flapper. It doesn’t matter if the fan is on low and anywhere in between up to high. It makes the same clicking noise continuously until I turn the compressor off and then it lasts for about another minute before it goes away with the fan still blowing. Has anybody had any similar problems with this? I don’t want to take it to the dealership and have them charge me hundreds of dollars for something that I can fix myself. Once I turn the compressor off and the fan is still running, the noise goes away after about a minute

 

That might be the "blend door". See Blend door actuator. The video at , although for a 2012, will give you some idea of what is involved in its replacement.

 

Thanks for the link and the video John! I read about the blend door in another thread and it continues to click even though I turn my temperature all the way down which I would think would close the fresh air door. I’ve never had a problem with it cooling or heating properly on either side. Unfortunately, mine is not as accessible as in the video because I just looked it need the dash near the center console so I’m going have to look at a diagram to find out where it’s at. I will check into it further thanks