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How to tell if EAP is using brakes?

Discussion in 'Model 3' started by insaneoctane, Jun 5, 2018.

  1. insaneoctane

    insaneoctane Active Member

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    EAP isn't as smooth as I'd like when cars change lanes across in front of you, or if you change lanes, etc. I suspect it's using friction brakes during these events where I would likely just have lifted the accelerator. Is there any way to tell if EAP is using the friction brakes vs regen?
     
  2. Tam

    Tam Active Member

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    In my S or X, I would just look for the brake lights from the icon car from the instrument clusters and I keep my right foot ready at the brake paddle so I know when exactly it uses regen only and when it uses the brake paddle as well.

    I imagine there's a similar way in Model 3 even when there's no traditional instrument clusters.
     
  3. lairdb

    lairdb Member

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    In the 3, regen braking actuates the brake lights, both in reality and on the icon -- are you saying it doesn't on the S or X?
     
  4. ChrisPDX

    ChrisPDX Member

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    Probably not the best idea, but you can look at the brake pedal. It drops about half an inch or so when the system actuates it. Maybe keep your foot next to it to feel if it drops could be safer. I'm not sure if you could somehow prevent the braking action if you block the pedal though, so be careful! If it's just using regen, then the pedal doesn't move.

    The car on the display showing brake lights doesn't work as they can come on with a strong enough regen.
     
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  5. Tam

    Tam Active Member

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    Yes! I can see the brake lights from S and X icons in the instrument clusters:

    In this picture below, it was pure regen because my foot was at the brake pedal and my foot felt that the pedal did not move at all while the rear brake light indicators went off and the car decelerated from 23 MPH down to 7 MPH:

    [​IMG]


    If it's dark enough:, I can see the red brake light reflection bouncing off from the rear toward the front and I can also see from the rearview camera/mirror.



    Since my foot is ready at the brake pedal, I know when the Autopilot only brakes by regen because the brake pedal does not move or mechanically only because I can feel the brake pedal moves.
     
  6. Twiglett

    Twiglett Single pedal driver

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    Model S, X and 3 all light the brake lights during regen if its slowing down fast enough - its in the manual believe it or not.
    The lights going on doesn't mean friction brakes are in use.
     
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  7. Adrien

    Adrien Member

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    .2G deceleration the brake lights come on
     
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  8. Randy Spencer

    Randy Spencer Member

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    It sounds like you can feel for the friction brakes being used, but I always just watched the gauge showing regen, if it's generating a lot of power when it slows dramatically that always seemed to indicate no use of the actual brakes, but I like feeling for the pedal moving better.

    I do wonder if the settings for acceleration and regen are used by the autopilot. It seems that when I set the car to Chill, or set the regen to Low I don't notice a difference in how the car drives.

    -Randy
     
  9. chronopc

    chronopc Active Member

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    I'm pretty sure it's friction breaks and not regenerative breaks. I don't see the regen meter turning green when I use EAP.
     
  10. Twiglett

    Twiglett Single pedal driver

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    I’d get it checked then if you don’t have regen set to low. My car often slows down with regen, even for the more forceful deceleration but I’ve got regen in standard.
     
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  11. chronopc

    chronopc Active Member

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    You're seeing regen when you're using EAP?
     
  12. Tam

    Tam Active Member

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    Yes when it uses regen as seen in the picture above:

    On the left of instrument panel is energy consumption meter.

    If you can locate "kW".

    It's regen when the animation near "kW" is green which is in this case.
     
  13. insaneoctane

    insaneoctane Active Member

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    Me too
     
  14. Yonki

    Yonki Deep Blue Metallic LR Model 3

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    I'm seeing regeneration with TACC braking on my Model 3 as well - in fact (per @Randy Spencer's comment above), the most regen I ever see (energy bar moving farthest to the left) occurs during TACC deceleration when a car cuts in front of me.

    So it's definitely using regen, the only question I have is if it's 100% regen or if it's also applying the brakes. Under some circumstances of course it will have to apply the brakes. I just don't know if/when there's overlap or if it's a hard switchover.
     
  15. insaneoctane

    insaneoctane Active Member

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    I'm pretty sure TACC is applying more brakes than me because it is hyper active and I am calmer....
     
  16. rhaekar

    rhaekar Member

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    I definitely see a lot of regen used when using AP. The bar goes green when it's in regen and the green bar goes further left if you're getting more regen.

    Brake lights on the car icon show up when it's using a decent amount of regen or friction brakes.
     
  17. chronopc

    chronopc Active Member

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    I took a road trip after getting the update and I definitely see regen when EAP brakes.
     
  18. RLC3

    RLC3 Member

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    I think I can tell when the mechanical brakes are applied because there always seems to be a detectable 'bump' when they get applied. It seems to me that regen is very smooth. When slowing calmly (like for a lower speed turn) the deceleration seems smooth. But on those rare occasions where someone cuts in and triggers rapid braking, or when one of those mysterious phantom braking events occurs, I think I feel the brakes grab - which I interpret as the mechanical brakes being applied.

    Does anyone else notice this?
     
  19. Randy Spencer

    Randy Spencer Member

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    I thought it might be, so I started watching for cars that were going to cut me off, and then observe the regen. It JUMPS when the car slows rapidly. It makes it difficult to know if the brakes are used in the deceleration.

    -Randy
     
  20. drawfour

    drawfour Member

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    I really would expect that regardless of your regen setting for driving yourself, it's full regen all the time when you have AP engaged, and it will be smart enough to apply disc brakes as necessary.
     

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