Strange sound during regen braking and feels like brakes are catching and releasing at speeds between >20mph. Randomly started yesterday. Ideas?

[Hojoooo]

I have never had any issues with my 2021 performance Model Y. Yesterday, I took a trip to the bank and the car was fine. When I left and got on the freeway, I noticed during Regen braking, my car began to make a loud scraping noise and it feels like the brakes are catching and releasing. This has never happened before and only occurs with regen braking, not acceleration and only at speeds above 20mph. My car has about 80k miles. Anyone else experience this problem?

 

[QtownTaxiGreg]

I know it's not supposed to brake with the brakes under normal regen braking. It sure sounds like it is though, because a scraping sound is what you get when pads are about done for.

Any chance you are braking a bit hard with a full or cold battery from time to time?

 

[Hojoooo]

I know it's not supposed to brake with the brakes under normal regen braking. It sure sounds like it is though, because a scraping sound is what you get when pads are about done for.

Any chance you are braking a bit hard with a full or cold battery from time to time?

Thanks for the response. I rarely use my brakes and when I do, I don’t normally need to brake hard, I don’t charge fully I’m set at 85%, it has been cold recently here in San Diego but this began strangely in the middle of the day yesterday after I had already done plenty driving. I’ve tried to play with the rotor shields as well. No luck, & Tesla is saying I can’t be seen until Friday.

 

[Pianewman]

Hojoooo: 80 k miles, and you rarely use my brakes? Have you done a visual check?

Since EVs don't use the hydraulic brakes very much, it's possible there's enough oxidation on the rotors to cause this problem.

If you see a lot of discoloration, I'd ask Tesla about doing what I think they call "burnishing." Or, charge to 100%, find a hill, and do some heavy, long downhill braking. I've done this 3-4 times with my 53k mile MYLR, to eliminate brake squeal while reversing.