High pitched sound normal?

If they can fix a brake issue with a software update, perhaps they can fix this noise issue, or at least install sound dampening material.

 

That would be true if there was a noise issue. There isn't.

 

Hi Splautz - I just drove my 2010 Prius off the lot and I too noticed a high pitched noise as you described. Has your noise problem gotten any better with time? My car had 3 miles on it so I thought maybe it's a newness factor. I test drove a few other Prius's and the noise just doesn't seem as audible as mine. Please let me know if there is any updates to your noise problem. I am thinking of taking my car back to the dealer to check up. Thanks in advance for your input!

 

High pitched sound is VERY annoying. Love the 2011 Prius but hopefully Toyota will look into this. Call them to report your experience at: 1-800-331-4331. Some days the noise is louder than others.

 

I am not sure if you have experienced the same notice. I was able to recorded it. Here is the Youtube video

I went to my dealer (Antwerpen Toyota in Clarksville MD) 3 times and ask them to check it but they couldn't find anything wrong.

 

That doesn't sound like the normal inverter whine, although it's hard to hear on the video. Inverter whine is fairly steady, like what you hear with an ultrasonic cleaner or the flyback from a tube TV set.

Tom

 

The noise I hear sounds like the whistle from an A/C expansion valve. I only hear it occasionally (I'm 44 so that might make a difference). It happens when the climate control is set to "off", so I doubt it's the A/C itself. It would drive me bananas if it were really loud, so it's understandable why people would complain.

 

I think that the inverter whine sounds like the monorail starting up in Disney, or a metro car (DC or Paris). It doesn't sound like static. The only "unusual" sound I'm wondering about in mine is that the display unit on top of the dash (HSI) has a buzz to it when the car is silent (like when no other noise is around). I didn't remember that from day 1 (although the car is only on day 18 )

 

The sound is high- pitched and isn't always on. One way to describe it is like a ringing sound in your ears. I'll try to think of other ways to describe it! I have tried using the radio to drown it out but can still hear the noise. Not sure what to do at this point. Suggestions, anyone??

 

Go to a few rock concerts and spend some time in the front row?
:rockon:

 

The sound is similar to the 16kHz noise from CRT televisions. Many people cannot hear frequencies that high, but if you can it is very annoying.

Does anyone know if there is an operating frequency around 15kHz or so that could be resonating enough to be audible? Despite people saying that this could never be fixed, one can certainly change the frequency that you're operating at and take it out of audible range. I don't mean for this generation, but maybe next time. The reason TVs have the noise is due to the horizontal scanning frequency.

 

Does anyone know for sure WHERE the noise is coming from and WHY? I was in a parking garage yesterday and experienced the noise at its loudest (no surprise). Anyone with a 2nd generation having the same issue?

 

I mostly hear mine make a whine sound when in my parking garage at work. I did however see a black GIII Prius make the exact same sound in a parking garage nearby while I was walking.

Mine kind of has a turbine-whistle type sound. Kind of like the sound an electric train makes.

 

Been there - done that!! Very funny!!

 

If it's the high pitched whine, then that comes from the inverter.

Tom

 

There are very quiet, high pitched electrical sounds I hear out of my '11 Prius. I love it though. It's the sound of electric driving baby

Beats the heck out of stupid conventional ICE cars that lack much in the way of brains.

 

roll down your windows, drive through town, then tell us how you like the sound

 

In the quick start DVD, they demonstrate high pitched sounds coming from the electric motor area. It does seem to be more pronounced than the 2nd gen, but I'm not bothered by it.

I'm pretty surprised how quiet Leaf is. I don't think it made any sounds going around the test track. Must be some sound though.

 

Just wondering if Toyota's Prius inverter cover would help. Toyota should give this away to anyone who complains about the problem.

It sells on ebay for $135

TOYOTA GENUINE PRIUS ENGINE ROOM INVERTER COVER JDM PANEL 2009 2010 2011 2012 | eBay

For future cars, Toyota should consider adopting Honda noise cancelling technology which counters road/other noise with a offsetting sound generated by a speaker in the cabin.

 

As an electrical engineer specializing in power electronics (among other things), I can tell you that high pitched sounds from various switching power supplies is normal. Large power supplies (motor drives like the ones in the Prius, various industrial equipment) have an operating frequency in the audible range. Smaller power supplies generally operate at much higher frequencies, but some of them will drop into the audible range when "period skipping" at low load. Motor drives can also make all sorts of interesting noises from shaping the output current.

As for why some units exhibit more noise than others, the oscillator frequency might be different (probably not the case with the Prius since it most likely uses a FPGA or ASIC with a crystal oscillator), component tolerances might be different, there may be variations in the mechanical assembly, etc.

BTW, my new PC has an interesting bug/feature: if the (room) window is open and I move the mouse when the system is idle, the neighbor's dog sometimes starts barking. Not planning to fix since I generally do not leave the high performance subsystem running with no load.