Puttster

I have the dreaded constant click clacking noise from behind the CD player. Lots of different and maybe even conflicting solutions here and they all look complicated! Where I live (hot), I don't need floor air, maybe even not defrost air. 90% of the time the in-your-face vents are fine. Is there a way to bypass that noisy motor and fix the airflow to go through the vents?

gomeybear

I believe the servo motor closest to you if your sitting in the passenger seat is the one that controls the damper for air either going to your face or feet. I would think you could probably disconnect the power source to it and that would probably fix the click clack noise but you wont be able to ever mess with the air distribution.

Puttster

So the default (no power) air flow is through the vents? That would be great for summer and okay for winter. What about the defrost vents, they would be nullified also?

salimshah

There is no default position.

In Auto mode, the mode servo is directed by the ecu to change flow. The servo reports back the ecu where the current position is. This almost perpetual motion ends up wearing down the system.

Take the A/C out of auto and use the button to set the mode you want. Assuming the servo motor is strong enough the system will go to that position of will keep trying to go to the desired position. Once the signal goes back to the ecu it stop any further motion.

You can pull the servo plug once you get to the desired mode. Much easier if you switch out of auto.

For defogging purposes, I would not take the servo out.

Salim

Salim

Puttster

So the clicking is coming from the front (mode?) servo, the one that is easy to pull out?

jwigley

Yes, very easy. 4 bolts to get the glovebox off and a couple small screws holding the mode servo in. The air mix servo is the pain in the ***.

jwigley

I swapped out the mode servo in mine, was quick and easy.

jwigley

I just reread your question. I misread it.

There is no way we can tell if it is your mode servo or mix servo that is making the noise.

You have to look and see yourself.

Puttster

okay, thx. I'll get under there with the fan running and I should be able to see or feel which one is the problem. Hopefully!

jwigley

You should be able to see it. And remember that both of them might be bad. That's what happened to me.

It is harder to see the mix servo in the back and I only swapped out the MODE servo at first. This was the louder obnoxious one that made the most noise in my car. The air mix servo still makes noise sometimes, it's quieter in my car and I can barely hear it sometimes with the radio and air blowing. I can make it go away if I quickly make the AC go to maximum HEAT and then move it back down to the temperature I want. I have the replacement unit, I just haven't gotten around to it since it's more of a hassle.

The air mix servo can make the clicka clicka noise even if I don't have my air on, when that happens, I turn on the AC, crank the temperature up to max HEAT and then turn it off. This puts the servo into a position that it can reach and it stops making the noise.

Puttster

Thanks, It'll be nice to turn off the radio!

jwigley

No prob. The tips I gave to shut it up are only temporary though. Best to just replace them right away and get it over with. Do it yourself and definitely don't take it to a Lexus dealership, they charge about $500 per servo, they would probably charge around $1500 to replace them with labor. You can do it yourself for less than $300.

There are some videos floating around that show an easy way to get to that hard to reach screw on the air mix servo.