Cleaning Servo Contacts (irritating Noise)

[drmull]

Hello - I have the annoying clicking servo that drives the AC mode function. I popped off the glove compartment as described in an earlier post and watched the servo doing it's clicking/moving thing. With some difficulty I got the servo out - I have no idea if I'll ever get it back in! The instructions below say to "clean the contacts on the outer part of servo also w/alcohol". Exactly where are these outer contacts? Does that mean on the outside of the box? If so, I don't see anything metal except the little post that engages the worm gear. It has a little grease on it. Are these "outer contacts" inside the servo box?? PLEASE help if you've done this - I want to do it right! I'm not sure I understand the part about cleaning the multiple wiper fingers w/alcohol but then putting contact grease back on them. What am I cleaning off the contacts? Sorry for so many questions.

"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."

[metah24]

replace the servo..there's no way to fix it. You might as well replace the other one too..There's 3 all together but the 2 always go bad or make noise. the only one u dont have to replace is the fresh air or recirculation one.

[drmull]

Well, that's depressing! Any sources for the part besides the dealer? Mine wants $200 for the servo. Thanks

Update - What the heck. I already had the stupid thing out and the contact arms were blackened so I cleaned them off. Worth a shot, I say. Now if I could figure out how to get the 3rd screw back in I'd fire it up...

[drmull]

Another update, although nobody seems to care but me! At least it might encourage someone in the future with the gerbil behind the dash. I got the cleaned servo back in and it has not made one peep in 2-3 hours of driving. It used to chatter constantly. I count it as a small victory...just hope it lasts.

[bluestu]

I really appreciate the info that you have provided!!! That noise is driving me crazy and I'm going to follow your instructions on cleaning the servo. Thanks!!!

[esuen]

I really appreciate the info that you have provided!!! That noise is driving me crazy and I'm going to follow your instructions on cleaning the servo. Thanks!!!

I followed the instructions and removed the servo.

The "gerbil" noise still persists despite disconnecting this servo that was perviously described -- Btw, this servo controls the mode change. So, I listened in and dug in further by removing the white venting conduct, I traced down to a 2nd servo that was really the noise maker, at least for my wife's RX300. This 2nd black servo which seems to control the temperature, since it reacts to my change of temperature as I moved from HOT to COLD and back, is located directly below the 1st servo that controls mode change. The mounting screws for this 2nd servo is hidden behind two silver metal tube that was heated up and had burned me several times when I removed the 1st servo. I gave up trying to remove this 2nd servo to perform the cleaning described earlier since it's late and dark in the evening working under only a pair of garage outside lamps plus emergency power pack lighting. Perhaps a 2nd attempt some time in the future. Thanks for your valuable insight to this.

This vehicle is at 121,000 miles and had this noise problem for at least 30,000 miles. Btw, I just had a blown transmission (car ceased to move in ALL gears) and took it to the local AAMCO specialist to rebuild it for $3600 (incl tax). It was jerking a bit and the engine tends to stall initially. But after driving for some 200 miles, all the initial problem went away as AAMCO guidelines had claimed and the car is now good as new -- transmission wise -- came with a 3 year or 50,000 miles warranty. Now trying to work through a wheel alignment problem...

[Karl K]

I also had the clicking noise behind the dash and over the weekend decided to take out the servo and clean the contacts.

The culprit was the servo behind the AC pipes. It takes all kinds of tricks and an assortment of various screwdrivers to get it out and back in.

It was worth it. I haven't heard a click since.

Thanks guys

Karl

[Markl]

Hello all

I realize this is an old thread but the clicking in my '01 is driving me bonkers. Does anyone have a pictoral breakdown of the area behind the glovebox concerned with this repair. I had a pdf of the shop manual but I think that was several hard drives ago :)

doc

[Jeffstpetebeach]

Hello all

I realize this is an old thread but the clicking in my '01 is driving me bonkers. Does anyone have a pictoral breakdown of the area behind the glovebox concerned with this repair. I had a pdf of the shop manual but I think that was several hard drives ago :)

doc

Heres the pdf file your looking for. hope this helps

Jeff

Air_Conditioning__AC__file.pdf

[Markl]

Thanks Jeff

[riley999]

I'd like to attempt the repair of the air inlet servo motors on my Lexus Rx 330 2004 model. It's making the gerbil noises. Can anyone give a blow by blow description of the repair to include pictures of the areas that I need to access?

[riley999]

Hello all

I realize this is an old thread but the clicking in my '01 is driving me bonkers. Does anyone have a pictoral breakdown of the area behind the glovebox concerned with this repair. I had a pdf of the shop manual but I think that was several hard drives ago :)

doc

Heres the pdf file your looking for. hope this helps

Jeff

[riley999]

Hello all

I realize this is an old thread but the clicking in my '01 is driving me bonkers. Does anyone have a pictoral breakdown of the area behind the glovebox concerned with this repair. I had a pdf of the shop manual but I think that was several hard drives ago :)

doc

Heres the pdf file your looking for. hope this helps

Jeff

[riley999]

Hello all

I realize this is an old thread but the clicking in my '01 is driving me bonkers. Does anyone have a pictoral breakdown of the area behind the glovebox concerned with this repair. I had a pdf of the shop manual but I think that was several hard drives ago :)

doc

Heres the pdf file your looking for. hope this helps

Jeff

[riley999]

The PDF file provided by Jeff does not include pictures of the repair area in question. There's pictures of everything else on the AC system, but the AC servo motor area. Anybody have pictures of this area with a blow by blow description of the repair?

[code58]

The PDF file provided by Jeff does not include pictures of the repair area in question. There's pictures of everything else on the AC system, but the AC servo motor area. Anybody have pictures of this area with a blow by blow description of the repair?

Riley- This is a GS, NOT an RX, but close enough to give you a good idea, with lots of pictures. http://www.clublexus.com/forums/gs-second-generation/399744-diy-on-changing-servo-motors.html

[lenore]

Here is a great thread:

http://us.lexusownersclub.com/forums/index.php?showtopic=53999&hl=

[Karl K]

Hello all.

Last time I cleaned the servo contacts I took an eraser and thoroughly cleaned the comutator ( the disc that the fingers make contact ) before spreading the grease and that was over a year ago and it is still quiet.

[riley999]

The PDF file provided by Jeff does not include pictures of the repair area in question. There's pictures of everything else on the AC system, but the AC servo motor area. Anybody have pictures of this area with a blow by blow description of the repair?

Riley- This is a GS, NOT an RX, but close enough to give you a good idea, with lots of pictures. http://www.clublexus.com/forums/gs-second-generation/399744-diy-on-changing-servo-motors.html

Great. Let you know after I've attempted repair.