Ddk912

Wow. That makes a lot of sense. The key is usually in the back hall within about ten feet of the car. And yes it sounds like a pump running. I belong to several car owner sites and I have never received such consistently useful feedback as I do on this one. Thx.

budwom

by my experience (2013) the key has nothing to do with it. If the tank is at a certain level, the pump comes on, period....thankfully this forum saved me when I first heard the problem 8 years ago...I have the 1000 page manual, but how do you look up "buzzing sound?"

Ddk912

So are you saying, it is working as intended, and there is no actions required?

salimshah

If it runs and shuts off in less than 5 sec, you can ignore it. If it keeps coming on in less than 5 minutes then further investigation is needed.

Salim

budwom

mine has definitely run for more than five seconds, but has never been a problem....the car is nine years old and trouble free.

Note the comment above from wcoffman on 1-06-17 in which (on page 24) the owner's manual explicitly states you may hear the sound for "several minutes" and it does not indicate a malfunction....that's been my exact experience, I hear this fairly often....

salimshah

If you have had this from day one then I too would say ignore it. If on the other hand it has progressively developed then have it checked. One of the problem [I am not saying you have an issue] area is with ABS where a pump has to constantly build pressure if there is an internal leak. If this issue is not addressed in time, it shortens the life span of the pump.

Summary, know your vehicle and if there is an abnormal behavior, have it looked at the next service.

Salim

Ddk912

Definitely runs more than 5 seconds, but no discernible issue in almost 2 yrs and 30k miles. Just one of those things with modern cars I guess. That’s why it my wife’s.

budwom

Hey, I know you're a knowledgeable guy, but I don't get why you're persisting on this. Read page 24 of your manual...Lexus says it WILL run for several minutes and it does...I'm not going to check anything which is explicitly deemed normal. Why would I? I'm not sure you're even reading these posts thoroughly..

Sjgomoll

I was able to get the buzzing to stop be opening and closing my rear hatch. Makes no sense but it works.
I read a lot of guessing on this thread. What is truly causing this, what is its purpose and should I be trying to stop it?

budwom

as mentioned several times above in the thread, try reading your manual. Can't believe this is still a mystery to some.

Mksto

Our 2010 RX350 has started making a series of three loud rapid clicking noises after starting the engine and again a few minutes after the engine is turned off.

The sound is coming from behind the middle of the dash.

The attached video records the sound. This noise happens 3 times then it stops.

Any tips would be greatly appreciated. Love this vehicle!

Thanks so much for your reply!

Problem solved.
We backed off the panel below the glove box and then opened the glove box and removed the filter. The cavity was filled with grass from a nest. Once removed the noise stopped.

Hope to get a few more years with this vehicle!

Madcar

Check this video - sounds like the vent air blend actuator might be stuck or worn