# Phantom braking with May 2021 Model Y



## Milo (Apr 4, 2016)

Had a 4-day test drive of sorts with a brand new (5 miles on it) Model Y Performance this week. AP was limited to 75 MPH, and it was a May build, so I assume no radar. Phantom braking was not only present, but WORSE than my May 2018 Model 3 RWD. 

That said, the improvements in the car over the last 3 years are substantial. Nothing earth-shattering, but everything is just a bit better, a bit tighter, a bit better quality. Of special note, the Y has more comfortable seats than mine (which are the second gen seats, not the initial release seats), is much quieter, and all around better build quality. N

Nice work, Tesla. Hope you guys can resolve the braking issue with Tesla Vision. This will be the car we buy when we again need two cars later this year.


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## M3OC Rules (Nov 18, 2016)

Not too surprised about the phantom braking. Glad to hear they are making substantial improvements on the build! I'm hopeful they can fix the phantom braking over time.


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## dwoo (Aug 31, 2021)

New Model Y owner of a LR AWD - took delivery 2 weeks ago. After driving the car for 800+ miles including ~200 with autopilot/autosteer engaged, I have experienced 5 "phantom braking" incidents where the cause could not be attributed to any environmental factor. In one such incident, the car on a complexly empty freeway the car suddenly decelerated from 72 to 40 in just a few seconds and appeared to be trying to come to a complete stop before I disabled autopilot and accelerated back up to highway speeds manually. Had there been other cars in close proximity, especially following, this could have been disastrous. I can confirm that the phantom braking issue is real - real enough that the spouse now refuses to ride in it unless I promise not to use autopilot.


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## Bigriver (Jan 26, 2018)

@dwoo, it's a bit discouraging to hear of phantom braking still occurring on a car without radar (I'm presuming yours is) since Elon said radar was the source of the phantom braking. Yet I'm wondering if what you are describing is a little different than the historical phantom braking - it was a soul jarring slam on the brakes, that yes, would be dangerous if someone were too close behind. Your description sounds a bit milder, like a phantom slowdown. I still occasionally experience these. You actually don't have to take it off autopilot, just hit the Go pedal and that will immediately override the slowdown. I do believe that whatever error is causing this behavior will get worked out, but for now it takes some monitoring and overriding.

You are not the first to report a spouse who refuses to be in the car with autopilot. I'd suggest to build up your expertise with quickly overriding the occasional bad autopilot behavior, and perhaps that "ruling" can later be relaxed.

Congrats on the new car. Hope the experience the first 2 weeks has been more good than bad.


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## Klaus-rf (Mar 6, 2019)

I have a repeatable section of road where "phantom braking:" always occurs with AP engaged - certain times of day. It's a shadow in bright sunlight in the roadway from an overhead street light. I guarantee you radar does not see shadows.


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## francoisp (Sep 28, 2018)

There's a section of a road where the car systematically brakes and it's not due to shadows: that section of the road is slightly hilly and the car's cameras or radar gets confused. I'm curious to see if the FSD stack will take care of it.


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## shareef777 (Mar 10, 2019)

francoisp said:


> There's a section of a road where the car systematically brakes and it's not due to shadows: that section of the road is slightly hilly and the car's cameras or radar gets confused. I'm curious to see if the FSD stack will take care of it.


I have the exact same situation in my 3 with a VERY specific, VERY small section of road. It just passes a light and when completely clear of the light would brake immediately. Happens during the day or at night with absolutely nothing around. Happens 100% of the time. For the first time took my wife's Y (no radar) down that road yesterday and zero phantom breaking.


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## PNWmisty (Aug 19, 2017)

I had a phantom braking event when riding with my wife but Autopilot was not on. I asked why she hit the brakes and she said she thought a white sedan was a cop and she didn't know how fast she was going! 

I said, cool, better safe than sorry!


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