Good morning dear fellows,

I recently bought LX570 2011 model. Nice car. but recently I have been hearing a humming noise from beneath the driver seat. On checking, I saw the sound is coming from a controller (hopefully) which is under the carpet and just behind ac vent. The sound is coming when the ignition is turned on and stays all the time. No other fault has been noticed so far. All the seat position switches, memory, and the seat heater-cooler work as expected. But the noise is disturbing. Any idea what the component could be? The snap shows the device location. Actually it is under the carpet behind the ac vent. And I could not see the controller box myself :-(
A video is attached, and I hope you can hear it by yourself.

 

The amplifier for the Mark Levinson sound system lives under the driver’s seat and and under the carpeting. It has twin cooling fans. Possibly fan noise?

 

that def sounds like a broken or obstructed fan. and if something fell down that hole accidentally, that would be the cause.

maybe you can take a picture with your phone, pushed right up against the opening, and see something in there? or shine a pencil flashlight down that hole?

could also be a mouse built a nest in the fan...

there is a slim chance you could suck it out with a vacuum cleaner, but likely that carpet will have to come up

 

FYI the amp sits in a metal cavity under the carpet. Carpet is slit side to side to allow access. The twin fans are on the end of the amp nearest the driver’s door. The 4, 14mm seat bolts can be easily removed, and the driver’s seat just tipped back for access.

Rather than doing the flashlight, camera, probing thing, this is the best way to check things out under the seat. No telling what you may find under there. First time I did it I found 3 missing, expensive Parker 75 pens I had though I’d lost, some change, a few dry French fries, and a nice pocket knife I’d never seen - maybe belonged to someone at the dealership who drove it.

 

Indeed that is the sound coming from the amplifier. I have seen that myself. Kudos to the helping hands :-)
I have seen many a post and the same video from a different user.

it seems to be a common problem with the naughty fans. As of now, I haven't checked if it's faulty or something stuck on it.
Will keep posted once I have time to look into it.

Again thanks a ton guys.

 

if it is JUST a blown fan, you can probably order a replacement from some place like Digikey. you just need to know the dimensions, the mounting hole positions, and the voltage (likely 12vdc)

If the existing fan has a part number and mfg name, you might find the exact replacement on ebay

 

If you haven’t seen the ML amplifier here it is.

 

Shamsa - I just bought a 2011 LX and have the same buzzing noise. Were you able to confirm your issue was the amplifier fan and did you find a solution? New to the forum (or any forum), please excuse any slips of forum etiquette, it is unintentional. Thank you all for your help.