Hi folks. I've got a loud buzz/hum that kicks in above 25mph and goes away when I slow down. Audible in this video. It sounds like a cross between a phone vibrating on a table and angry bees in a cardboard box.

30 min of Googling has me looking at various threads on AC servos in GS and IS models. In my case, driving around the neighborhood now, it happens independent of whether HVAC is on/off, wipers are on/off, and accelerating or braking. Just speed sensitive. I'm not in love with the servo idea but that's all I've got to run with. Maybe the servo can't find its off position? Or have you got another idea.

Also, any good LS430-specific insights on fix, which servo(s), etc.? All I've been finding is for other models.

This is a new sound. I noticed a very little bit of something intermittent a few days ago, at highway speeds. Inconsistent. Today, it was very reliable on/off around 25mph in a trip to the hardware store for another project.

P.S. in the video, the sound starts right at the start of the vid, then shuts off at around 10 sec just before I speak. It's clearest at the end, kicking in at 33 or 34 seconds into the vid.

P.P.S. Edited to add video another way since that first link didn't work for some.

 

I can't get your video to play, but have you ruled out something loose in the glove box making the sound?

 

Not sure what the video problem is @TominPT , it is shared to anyone with the link. Sorry it doesn't work for you.

No, it's not something loose in the glove box.

 

Video will not play when I try also....

 

Played fine for me. It's an MP4 file so you may need to install something that plays MP4s if you don't already have it.
Damn that's loud. Sounds like something is hitting a fan blade and it comes on suddenly rather than building up.
Is it localised to that area where the camera was or more general?

I'd suspect something loose in the vent system that is being blown onto a ventilation fan above a certain speed.
That speed will vary slightly depending on outside wind speed and direction.

 

I edited the OP to add another way to get to the video.

@BigBoomer , that's a good thought that I'll look into. Perhaps I can fish in the ducts and blow of vacuum things around. I had the fans off when that noise would come and go, but I guess they could get blown on by airflow or have minds of their own. I think that's what you're saying.

From what I can tell looking around at other people's problems, It doesn't seem to be the typical mad servo noise.

 

Have you ever inspected the cabin filter? Try driving with glove box open and search for noise. Can you have someone else drive and you actively search when driving around 25mph? The noise seemed to slow down as you were decelerating. I just re-read you post and you said it occurs regardless whether HVAC is on or off, so probably not the cabin filter/fan.

What about the sunroof? Try inspecting the sunroof for leaves, debris, etc? Try driving with it open or closed, etc. Again, see if someone else can drive the car as you sit from the passenger seat and furiously search for the "cardboard box of angry bees"! lol

Another way to know whether it's debris or something moving from WIND is to put the car up on jackstands and 'drive' the car to around the 25mph mark? Obviously that will take some time to set up jackstands, but I think that will further identify whether the noise is something that is inherent to the car (circuits/servos/moving-rotating shafts etc) or if it's simply debris being blown by the wind force at 25mph.

 

^ good suggestions. Thanks, @LS430inDE. . Actually, the first time I heard it was MUCH more intermittent and sunroof was one of the things I thought it might be. I opened and closed a few times but it didn't seem to matter.

My plan is to take the glove box door and back off, inspect cabin filter, and then have my wife take me for a ride. I'll bring a bit of hose to try as a poor man's stethoscope. It'll be a while but I'll post results when I have them.

Don't let that stop the good ideas from flowing, though!

 

The issue was loose clear tape covering the chrome trim across the top of the windshield, flapping in the wind. The noise was higher up than I thought at first.

Here it is just for a pic, after I pulled it off and drove around buzz-free. Weird.

I don't see similar tape on other trim. Is it normal?

 

<LOL> That's assembly tape that should be pulled off by dealer during pre-sale prep.
There to protect the chrome during assembly and shipping.

 

Glad for you that you discovered the source and was able to remedy!
Your issue is a good example of how a sound from a car may appear to be emitted from one particular area of a car when actually coming from a different area of the car, and how the cause of sounds may be influenced by varying external forces, and how a sound is heard may be influenced by various factors and the way sound travels.

 

That's what I figured. It did its job and then some.