jmcohen23

I have a '99 RX300 with 95k miles. Recently, I am hearing a constant noise coming from underneath the dash on the passenger side. The noise sounds like the fan switching modes/stirring. This noise occurs both when the air is on and off. Has anyone else had this problem? I took my car in the local dealership, and the service consultant suspected that it could be the blend door motor.

Anyone with any insight would be greatly appreciated. I made an appointment for Wednesday, July 18th, so I'm hoping someone can shed some light before I go in.

thanks!

--jason

VVT-i

One of your AC servo motor goes bad. They are two of them one for the air mix and another one for Mode( Face, foot,ect..). The tech have to figure which one is bad by taking the glove box out and reach his hand to feel it.

I know the part is around $200.00 for each servo and the labor on the warranty book is 4.1 hrs,but it can be done without taking the dash out.

I hope your is making the noise all the time because some of the problem I've seen is intermittent and it is hard to say which one is making the noise.

Meetya

First, make sure it is not your CD-changer. Take the CD-cartridge out.

jmcohen23

thanks for the replies. The noise on some days is constant, other days it is intermittent.

I'll check the CD player (good idea), but I'm pretty sure it's the A/C b/c whenever I switch A/C modes, I hear the same noise.

jmcohen23

Well, I took the car in and they said it was the "Air-Mix-Motor". They said that it should be replaced b/c during the winter time, the motor will not distribute the air evenly or even properly. Total cost is $751 ($190 for the part).

Fern

I just recently started to notice the same sound.

Not going to change it... Think its time to start shopping around for alternate vehicle.

thomas1

it may be this(from another forum)The noise is coming from the servo motor that moves the door for the "mode" button. This servo moves diverters to change from vent to floor, etc.
- I popped the bottom panel off under the glove box.
- I then removed the glove box assembly. 2 screws up high, 2 bolts down low.
- With the key on engine off you can press the mode button and watch the servo move. Turn the key completely off.
- Remove 3 screws and plug to take the assembly out.
- Do not attempt to rotate the arm on the end of the servo. It engages w/ a worm gear. Turn it and you will break gears.
- The servo is a snap together unit. Carefully take it apart w/ the arm side down.(so gears don't fall out)
- inside you will see multiple whiper fingers that make contact w/ a gear. Carefully clean these w/ alcohol and a cotton swab.
- Redistribute the contact grease on the whiper pad w/ a clean finger (any oil or lotions on skin will mix w/ the grease and make the copper contacts corrode.
- Carefully snap unit back together.
- Clean contacts on the outer part of servo also w/ alcohal.

The other option is to have Lexus diagnose this for you and hit you for $160 for the part plus ~ an hour or 2 labor.

So far the noise is gone and the HVAC system works properly. I will post any updates if the problem comes back. I think the problem was caused by crusty contacts in the servo that were creating a poor signal back to the computer that controls it. Now that it has a clean signal, all is well..... I hope!!!

Lexish

Hi, did your fix/cleaning of the a/c servo motor stay fixed? How long did it last?
I just went to Lexus Service & they want $484 to fix the A/C servo motor. plus $334 to replace driver side seatbelt. Needless to say, I'm looking for other options.

kosmik

my girlfriend suv rx300 had a high pitch squeal coming from the fan when it was on. the higher the fan speed the louder. she took it to a few shops and all told her the bearing in the motor were gone, very expensive to fix.. Well i looked at it and found that the cabin filter in the glove box cover fell off and some stuff from the glove box went into the fan. I removed the debris change the filter and no more noise...

ricco750

Refer to the instructions given by Thomas1 three posts earlier on this page, and read the following link.

https://www.clublexus.com/forums/rx-...ich-servo.html

I rebuilt both my air mix and mode servos two months ago, they are still working normally and no more "gerbil noise". Even if you want to buy brand new servos, they are available on line for about $150 each. That $751 quote is ridiculous, a good tech could replace both in about 30 minutes.

bob2200

I don't see any posting by Thomas1 there.

ricco750

Sorry, I should have been clearer...I meant the Thomas1 instructions on this page...two posts before my original.

az-dave

I now have this dreaded sound too. Printed out the diagram and will take apart in next week to see which servo is making sound. Its definitely not radio or fan related because sound happens regardless if fan is on or off, and happens when stereo is completely off.

maxSteel

This thread has great pictures
https://www.clublexus.com/forums/rx-...-cold-air.html

$750 to replace the mix servo is insane. Its a pain to remove but not a $561 labor charge pain.

You get get the servo for a lot less on line too

code58

That's not insane.... that's WAY beyond insane!