Buzzing sound when brake pedal pressed

[Ravire]

When I fully press the brake pedal while the car is plugged in as far as it goes there’s a loud buzzing sound, is this normal? This happens every time the car has been exited, plugged in, locked, and sat in again. But when the car is on it’s not there. Is this something I should be concerned about, as it’s fairly loud.

 

[Ravire]

IMG_0459.MOV

 

[Mash]

It's not normal. Did you recently do anything about brakes? Most certainly worth SC visit. Best case scenario is air in the pump. But it more sounds like pump bearing got broken.

 

[Ravire]

Nope brakes haven’t been worked on, I haven’t thought much about it since they seemed to work fine when the car was on. Does mobile service do brakes? Don’t really want to go to a SC with Covid-19.

 

[Mash]

Nope brakes haven’t been worked on, I haven’t thought much about it since they seemed to work fine when the car was on. Does mobile service do brakes? Don’t really want to go to a SC with Covid-19.

I wish we had here any mobile service. But that doesn't sound like mobile service fixable issue. You just might lose brakes booster potentially, so be ready to press much harder in such case.

 

[Ravire]

Okay thanks for the heads up

 

[Mash]

Okay thanks for the heads up

Oh, oh, and don't forget that if you keep pressing parking button while driving - it will start engaging emergency stop on rear brakes even if whole hydraulic system has completely collapsed. Most people don't know...

 

[Ravire]

Oh, oh, and don't forget that if you keep pressing parking button while driving - it will start engaging emergency stop on rear brakes even if whole hydraulic system has completely collapsed. Most people don't know...

I did not know that that’s really useful thank you

 

[Dolemite]

I've actually noticed this and didn't bother posting about it because this car is full of weird quirks. I'm willing to bet a lot of money that everyone's TM3 on here does this... it only happens when it's plugged in and you gotta mash it pretty good.

I don't think it's an issue. The probability of a modern car's brakes failing is infinitely small... so no cause for concern IMO. As to what it is - no idea. Would love an answer... definitely something to do with the brake assist, but why it only does it when it's plugged in is beyond me.

 

[Mash]

I agree - complete failure is not very often unless you really change brakes or stop servicing them for dozen years or go to track and make few hot laps ignoring that they fade or car shop didn't tighten bleed valve good enough. Brake fluid leakage will be reported by the car itself.

But brake booster can fail suddenly. So it's important to remember to push really hard if car doesn't stop + test beforehand emergency brake on an empty road and actually use it when needed.

 

[Ravire]

I sent the video to the tech at my local SC and he said all the model 3s he’s seen do this. He said he believes that the brake booster is getting partial power while charging.

 

[Mash]

hm... Maybe your video exaggerating sound level?

 

[Ravire]

It seemed louder in person tbh

 

[Mash]

Then I don't have such noise at all

 

[Ravire]

Hmmm that’s weird I wonder if there’s any correlation to build date? Mines a 3/20