HumanMale

Hi all,

Recently (last three months really), I've been noticing an oscillating squeaking noise coming from the passenger side of the dashboard on my '07 LS460. I've troubleshot the problem and have it isolated to coming on only when the A/C is turned on (recirculated or outside air- doesn't matter). When the A/C is off, the sound goes away.

No other squeaking noises at all coming from anywhere else on the car.

I have a sneaking suspicion it's related to the tensioner belt connected to the Air Conditioner, but I'm honestly not sure at all.

Before I take it into the stealership, I thought I would consult with you knowledgeable gents first to see whether anyone might have any ideas before they try and sell me a new tensioner assembly (C$506 before taxes and belt replacement costs- I.e. just the tensioner assembly).

Might this be a more relatively simple belt issue? A/C is running pretty much all the time when the car is on- wouldn't be surprised at all if we've simply worn the belt through.

I found this link outlining a similar problem, but again- I'm not entirely sure I want to go the route of the full tensioner assembly replacement if it's likely just a belt: https://www.clublexus.com/forums/ls4...t-curious.html

Thanks all- any ideas are appreciated!

Nospinzone

It might just be a worn belt.

Another possibility if it sounds like it is inside the car rather than the engine compartment, is the recirculate flap behind the cabin filter inside the glove compartment. Was that filter changed recently?

LordBowral

I have the same issue and describe the noise like a small duck squeaking inside the glove box every 10 seconds only when the air cond has been running for a long time ... They look at me like I'm mad at the dealership ! The only thing I havent been able to fix ... Mine is an 07 also

jud149

Blower motor???

HumanMale

I have a sneaking suspicion it is just the belt. The sound indeed does sound like a duck or something inside the glove copartment; just generally annoying.

As for the air filter, I did just have it changed about 6 months ago. What do you mean by could be the recirculate flap? The noise comes regardless of whether it's set to recirculate or not and sounds like a pulley to me if I were to hazard a guess.

HumanMale

Interesting. Is the blower motor located in the glove compartment? I was under the impression it was controlled by a belt connected to the tensioner assembly and did not have a motor... But I am certainly not sure about that at all.

Is the blower motor right behind the glove compartment?

jud149

I believe so. Have a look.

https://www.clublexus.com/forums/sc-...fan-speed.html

HumanMale

Interesting again- thanks for this.

Don't think it's the blower motor though. A/C's working just fine - just the (increasingly) annoying squeal/squeak. I'm really leaning towards a worn belt. HOWEVER, could the blower motor fan itself be causing the squeak too (i.e. improperly lubricated bearing assembly?).

I think I'm at the point where I've gotta' take it into the stealership ...

Devh

If it were me and I suspected the blower motor bearings making the noise I would get a mechanic stethoscope and probe the area to see if I can isolate the sound. If I suspect it could be the belt I would turn the engine on and probe the area around the Idler pulleys.

jud149

Blower motors can definitely make weird noises including what you describe.

HumanMale

If it turns out to be the blower motor, is that a DIY job for someone living in a condominium apartment with only a socket/screwdriver set? If so, anyone done it before or have a guide they could point me towards (a subsearch of this forum for "blower motor diy" turned up nothing).

Thanks!

jud149

To determine if it 's the blower motor, you should be able to turn it on with the ignition on, engine off.

HumanMale

Brilliant. I'll keep my fingers crossed that my battery holds (I killed it when I was buying it last year by keeping everything on while the wife and I were in the car without the engine running!).

I'll report back to this post for posterity once I've made a determination.

efxonly1

HumanMale, I was hearing that same squeal every so often for the last few months, and then a few weeks ago the blower motor behind the glove box starting making a humming noise when I went over certain bumbs. The dealer replaced the blower motor or something related to it this past Friday and I haven't heard the problem again so far. Covered under warranty.

HumanMale

Yeah, I think it's the blower motor, although still not certain.

Definitely not a belt- engine compartment was purring like a kitten. Only heard the noise in the cabin, and when I removed the panel in the glove compartment leading to the air filter (together with removing the air filter itself) and ran the fan on max, I heard the squeal loud and clear coming from the general vicinity of the blower motor.

I pulled the motor last night- very simple task (https://www.clublexus.com/forums/ls4...ement-diy.html), and ran the motor outside of the housing.

The motor itself looked fantastic- no signs of wear at all and only minimal, expected dust buildup on the fan blades (see pic attached).








Holy crap is that thing ever powerful. Adjusting from low to high fan speed I could feel the motor really kick it up literally, in my hand. While it was in the housing immediately before I pulled it out, I could hear the squeal. While it was in my hand after having pulled it, after adjusting through various speeds, no squeal at all.

I took it out, spun it around a few times in each direction and then put it back into place. Drove it around for 20 minutes or so and only heard the squeal when I adjusted the fan speed manually- did not occur during regular driving.

I think it has something to do with the backpressure created by the vacuum in the confines of the blower housing and a weakened blower motor.

In short, I'm fairly confident that were I to replace the blower motor, it would go away completely. However, the motor still works fine, and as long as the squeal does not return on a full-time basis, I can live with hearing it the odd time I adjust the fan speed.