High Pitch Noise Coming From Dash

Hello all, I'm desperately hoping someone here is able to help me.

So I purchased a 2023 ORP this year, and am absolutely in love with it. The first week of having the car, I updated the firmware of the onboard navigation system, and I believe this problem started then.

Any time I push in the brake pedal, or turn on the blinker, a high-pitched noise (around 5khz) comes out of the dash. Now anytime I'm not listening to music pretty loudly this is extremely annoying as the pitch cuts through everything and I can't really enjoy a quiet drive in my car where stoplights are involved.

I found [this thread](https://old.reddit.com/r/4Runner/comments/lwi5ix/high_pitched_noise_in_cabin_when_pushing_brake/) on reddit of someone experiencing the same issue, and they seemed to think it was related to the tow light controller, which makes sense to me since both brakes and blinkers send signals to a towed vehicle. However taking it in to Toyota the tech said he couldn't hear the sound and didn't want to charge me for something they couldn't diagnose. Which I certainly prefer to them taking it in and doing nothing.

Has anyone else experienced this? Any ideas on what I could possibly do to diagnose and fix this on my own?

 

Maybe you could be more precise about where the noise is coming from. You said you can hear it when the brake pedal is depressed. Is that true even when the car is stopped? You could have a helper press the brake pedal while you hunt for the noise.

 

It's coming from behind the steering wheel, somewhere in that dash area. Yes the sound comes even if the car is off and the brake pedal is pressed (and also with the blinkers on)

 

Interesting. Maybe feel around under there and see if you can feel a relay vibrating or something. Also, assuming you can make it happen reliably, maybe take a video to show to the service advisor.

 

If the car is off, and the brake pedal is depressed sounds like the brake boost system is running. (It's electric.) I wonder if that could be it?