1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Sticky Brake Pedal Feel

Discussion in 'Prime Main Forum (2017-2022)' started by m8547, May 17, 2019.

  1. m8547

    m8547 Senior Member

    Joined:
    Aug 8, 2018
    927
    615
    0
    Location:
    Colorado
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    I've noticed that sometimes by brake pedal feels kind of sticky. It's hard to explain, but it almost feels like the pedal catches on something a few times as I apply or release pressure on the brakes. The pedal still moves normally, but I can feel a sort of light click through my foot. It seems to happen more often after moderately hard braking, while using "B" mode, or while I'm holding the brake at a stop. I don't think it's physically sticky, but it seems like whatever manages regenerative vs friction braking makes the pedal feel weird sometimes. Most of the time the pedal response is smooth and linear. But if it gets into this sticky mode it continues to feel sticky even during light braking or at a stop. It also makes some faint clicking sounds while at a stop, like a relay is clicking. Has anyone else noticed this, or do you know why it does this? If I only do light braking for a drive it never seems to do this, even though the friction brakes are still used like to hold the car at a stop.

    To be clear I don't think there is any defect with my car. I'm guessing this weird brake pedal feel is normal for Prius, but I've never driven another one.
     
  2. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,306
    1,328
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I can’t recall having experienced this, as best I follow you description.

    Any difference, either in how it feels or how often/whether it happens, EV vs. HV?
     
  3. m8547

    m8547 Senior Member

    Joined:
    Aug 8, 2018
    927
    615
    0
    Location:
    Colorado
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    Most of my driving is in EV mode, so that's where I've noticed it. Not sure about HV mode.
     
  4. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,306
    1,328
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I too mostly drive in EV.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    brakes are drive by wire, so there's not much mechanics going on. i would have the dealer look at the pedal, or take a close look yourself.
     
  6. FuelMiser

    FuelMiser Senior Member

    Joined:
    Jun 29, 2008
    1,263
    858
    0
    Location:
    Monument, CO
    Vehicle:
    2016 Prius
    Model:
    Touring
    I agree its normal in Gen 4 (2016+). My 2016 Three Touring (not Prime) has the same weird brake pedal feel. My belief is initial brake application involves the friction pads, then as regen braking takes hold, the friction pads are relaxed giving the sensation of less braking force. This behavior is more pronounced in the Gen 4 than in Gen 2 or Gen 3 (I've had all), making smooth modulation of braking action difficult and unnerving in certain circumstances.