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Hvac Fan / Blower Chirping / Screeching Sound

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My 2004 LX470 has nearly 120k miles on it and 5k miles or so ago I began to hear an intermittent chirping / screeching sound coming from the front passenger foot well area when the HVAC fan / blower was on and the noise has become more frequent since, although still intermittent. Below are some pictures of the referenced area. What is going on and how can it be fixed? Thanks!

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You might try removing the HVAC blower fan and look for debris that might be causing the noise. I had a similar noise in an LS400 a long time ago that I would describe as "chirping / screeching". A shop removed the junk that was contacting the fan and causing the noise - I think it was insulation that had come loose. I remember it being a cheap fix.

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So I removed the blower motor, but it was clean with no debris therein, as shown by the attached picture. Does anyone have any other ideas as to what might be causing the noise I hear? Thank you!

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Hi everyone,

Hope all is well.

I had the above problem a while ago, but didn’t do anything to fix it.

Nevertheless, I now have the problem where my HVAC fan / blower cuts in and out and does not constantly stay on. With the problem as described, would replacement of the part I removed and took pictures of above fix the problem?

AND, if so, where is the best place to get a good priced new replacement?

Please advise ASAP, as it’s getting hot here in NY.

Thanks!

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Hi again,

I called my dealer's parts department today, gave them my VIN and described my problem.

Unfortunately, they said there are several parts involved with what I am describing, including: the "Motor Assembly", "Servo Motor Assembly", "Control Motor Servo" and “Amplifier".

While the dealer was vague, can anyone please shed more light on this, including what the differences between the various parts are and which part is most likely to apply.

Thanks again!

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Only guessing, but that sound can occur when bearings fail. If you spin the fan cage by hand does it make any of the sounds? Does it spin freely? Of the items you mentioned ""Motor Assembly", "Servo Motor Assembly", "Control Motor Servo" and “Amplifier"", the only one that seems plausible is the motor assembly (that's a stab in the dark btw).

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Usually the servos make a clicking noise....I would think the blower motor bearings are dry. I am a kind of guy that would take it apart and see if a little oil on the bearing stops the chirp. Than you would know for sure. As for part, Suggest joining Club Lexus and use Sewell Lexus as they give a discount to Club Lexus folks. Other sources exist also. By the way a little three in one oil would be just fine. Tri flow oil is my choice but finding it may not be as easy....

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I have the same problem on my wife's 2000 LX. Is the blower motor etc in the same place on the 2000? I have previously removed the glovebox etc and the large Black plastic cover ect, behind the glovebox but never seemed to get in there deep enough to actually find the blower motor and fan. Should I be attacing it from underneath the dash, above the passenger footwell, as opposed to behind the glovebox?

I believe the problem is probably dry bearing(s).

Thanks.

BH

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Ok, fan assembly out. Good start.

Now, how do I extract the plastic blade assembly from the motor shaft? I've removed the circular spring clip but blades do NOT want to come off the motor shaft. I want to get to the shaft bearing and can not do so with the blade assembly in place.

Thanks.

BH

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UPDATE.

Actual fan motor now removed from the black plactic housing, albeit with hamster wheel blade assembly still attached to the motor shaft BUT it now allows much better access to the underside of the hamster wheel and the bearings on both ends of the motor.

Removed the motor from the plastic housing by removing the two screws on the end of the motor, gently prying off the small "cover" on the side of the plastic casing and then tapping the end of the metal motor, throught the opening made by the removal of the small cover. Whole motor assembly slid out from the black plastick housing.

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Washed entire motor out using spray electronics cleaner. Washed out all the 12 years of accumulated crap, then washed and dried hamster wheel.

Using a spray lubricant (with straw), lubbed up bearings at both ends of the motor and reassembled back in to the black plastic housing.

now all back in place and running almost silently but totally chirp/squeak free.

BH

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I didnt get a chance to do it to my 03 lx but my gs400 was doing making noise when the a/c is on. I change the cabin filter in the gs n the noise went away. I'm going try it in my lx & see what happen.

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BARNEYHYPHEN,

I know it's been a long time since this post, but I hope you reply. Where did you ultimately go to get the blower fan and motor out? I've also been behind the glove box don't remember seeing it there. I can't quite tell from the pictures at the start of this post if they are just the same area as where the cabin filters are replaced or somewhere else.

Tom Z

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