Tag: ABS

  • How the braking system works on Model Y

    Braking and Stopping Braking Systems

    WARNING: Properly functioning braking systems are critical to ensure safety. If you experience a problem with the brake pedal, brake caliper, or any component of a Model Y braking system, contact Tesla immediately.

    Model Y has an anti-lock braking system (ABS) that prevents the wheels from locking when you apply maximum brake pressure. This improves steering control during heavy braking in most road conditions.

    During emergency braking conditions, the ABS constantly monitors the speed of each wheel and varies the brake pressure according to the grip available.

    The alteration of brake pressure can be felt as a pulsing sensation through the brake pedal. This demonstrates that the ABS is operating and is not a cause for concern. Keep firm and steady pressure on the brake pedal while experiencing the pulsing.

    The (ABS) indicator briefly flashes yellow on the touchscreen when you first start Model Y. If this indicator lights up at any other time, an ABS fault has occurred and the ABS is not operating. Contact Tesla. The braking system remains fully operational and is not affected by an ABS failure. However, braking distances may increase. Drive cautiously and avoid heavy braking.

    If the touchscreen displays red (!) BRAKE indicator at any time other than briefly when you first start Model Y, a brake system fault is detected, or the level of the brake fluid is low. Contact Tesla immediately. Apply steady pressure and keep the brakes firm to bring the vehicle to a stop when safe to do so.

    If the touchscreen displays yellow (!) BRAKE indicator at any time, a brake booster fault is detected. Apply steady pressure and keep the brakes firm to bring the vehicle to a stop when safe to do so. Hydraulic Boost Compensation will be active.


    Emergency Braking

    In an emergency, fully press the brake pedal and maintain firm pressure, even on low traction surfaces. The ABS varies the braking pressure to each wheel according to the amount of traction available. This prevents wheels from locking and ensures that you stop as safely as possible.

    WARNING: Do not pump the brake pedal. Doing so interrupts operation of the ABS and can increase braking distance.

    WARNING: Always maintain a safe distance from the vehicle in front of you and be aware of hazardous driving conditions. While the ABS can improve stopping distance, it cannot overcome the laws of physics. It also does not prevent the danger of hydroplaning (where a layer of water prevents direct contact between the tires and the road).

    Automatic Emergency Braking is designed to automatically brake in situations where a collision is considered imminent.

    WARNING: Automatic Emergency Braking is not designed to prevent a collision. At best, it can minimize the impact of a frontal collision by attempting to reduce your driving speed. Depending on Automatic Emergency Braking to avoid a collision can result in serious injury or death.

    CAUTION: In emergency situations, if the brakes are not functioning properly, press and hold the Park button on the drive stalk to bring the vehicle to a stop. Do not use this method to stop the vehicle unless absolutely necessary.


    Brake Disc Wiping

    To ensure your brakes remain responsive in cold and wet weather, Model Y is equipped with brake disc wiping. When cold and wet weather is detected, this feature repeatedly applies an imperceptible amount of brake force to clear away water from the surface of the brake discs.


    Hydraulic Fade Compensation

    Your vehicle is also equipped with hydraulic fade compensation. This feature assists in monitoring brake system pressure and ABS activity for instances of lower brake performance. If lower brake performance is detected (for example, as a result of brake fade, or cold or wet conditions), you may feel the brake pedal pull away from your foot, detect some noise, and notice a strong increase in vehicle braking. Continue to press the brake pedal without releasing or “pumping” them — brake as you normally would.

    CAUTION: If brakes are not functioning properly, stop the vehicle as soon as safety permits and contact Tesla Service. If necessary, use the Park button to stop the vehicle in case of emergency

    WARNING: Always maintain a safe driving distance from the vehicle in front of you and exercise caution when driving conditions are hazardous. Do not rely on brake disc wiping or hydraulic fade compensation to act as a substitute for adequately applying the brakes.


    Hydraulic Boost Compensation

    Model Y is equipped with a brake booster that provides a mechanical advantage that effectively activates the brakes when the brake pedal is pressed. Hydraulic boost compensation provides mechanical assist in the event of a brake booster failure. If a brake booster failure is detected, the brake pedal may feel harder to press and you may hear some noise when you press the brake pedal. To stop the vehicle, apply adequate steady force on the brake pedal without releasing or “pumping” them. Exercise caution while driving and maintain a safe distance as brake pedal responsiveness and braking performance may be degraded.


    Regenerative Braking

    Whenever Model Y is moving and your foot is off the accelerator, regenerative braking slows down Model Y and feeds any surplus energy back to the Battery.

    By anticipating your stops and reducing or removing pressure from the accelerator pedal to slow down, you can take advantage of regenerative braking to increase driving range. Of course, this is no substitute for regular braking when needed for safety.

    NOTE: If regenerative braking is aggressively slowing Model Y (such as when your foot is completely off the accelerator pedal at highway speeds), the brake lights turn on to alert others that you are slowing down.

    NOTE: Installing winter tires with aggressive compound and tread design may result in temporarily-reduced regenerative braking power. However, your vehicle is designed to continuously recalibrate itself, and after changing tires it will increasingly restore regenerative braking power after some moderate-torque straight-line accelerations. For most drivers this occurs after a short period of normal driving, but drivers who normally accelerate lightly may need to use slightly harder accelerations while the recalibration is in progress.

    WARNING: In snowy or icy conditions Model Y may experience traction loss during regenerative braking.

    The amount of energy fed back to the Battery using regenerative braking can depend on the current state of the Battery. For example, regenerative braking may be limited if the Battery is already fully charged or if the ambient temperature is too cold.

    NOTE: If regenerative braking is limited, a dashed line displays on the energy bar.

    Stopping Mode

    Regenerative braking decelerates Model Y whenever you release the accelerator pedal when driving. You can choose what you want Model Y to do once the driving speed has been reduced to a very low speed (almost at a stop) and both the accelerator pedal and brake pedal are released. While in Park, touch Controls > Driving > Stopping Mode and choose from these options:

    • CREEP: When close to, or at, a complete stop, the motor continues to apply torque, moving Model Y slowly forward (in Drive) or backwards (in Reverse), similar to a conventional vehicle with an automatic transmission. In some situations, such as on a steep hill or driveway, you may need to press the accelerator pedal to continue moving or to prevent Model Y from moving in the opposite direction.

    WARNING: Never rely on CREEP to apply enough torque to prevent your vehicle from rolling down a hill. Always press the brake pedal to remain stopped or the accelerator pedal to proceed up the hill. Failure to do so can result in property damage and/or a collision.

    • HOLD: Maximizes range and reduces brake wear by continuing to provide regenerative braking at speeds lower than with the Creep and Roll settings. When Model Y stops, the brakes are automatically applied without you having to put your foot on the brake pedal. Whether stopped on a flat surface or a hill, Vehicle Hold keeps the brake applied, provided your foot remains off the accelerator and brake pedals.

    WARNING: Never rely on HOLD to adequately decelerate or fully stop your vehicle. Many factors can contribute to a longer stopping distance, including downward slopes, and reduced or limited regenerative braking. Always be prepared to use the brake pedal to adequately decelerate or stop.

    • ROLL: When close to, or at, a complete stop, Model Y becomes free rolling like a vehicle in Neutral. Therefore, if stopped on a slope, Model Y will roll downward. The brake does not engage, and the motor does not apply torque (until the accelerator pedal is pressed).

    NOTE: If you choose CREEP or ROLL, you can still use Vehicle Hold to apply the brakes. However, you will need to briefly press the brake pedal when the vehicle is stopped.

    WARNING: Press the brake pedal if Model Y moves when unsafe to do so. It is your responsibility to stay alert and be in control of the vehicle at all times. Failure to do so can result in serious damage, injury, or death.

    WARNING: Do not rely on regenerative braking and your chosen Stopping Mode to keep you and your vehicle safe. Various factors such as driving with a heavy vehicle load, on a steep hill, or on wet or icy roads affect deceleration rate and the distance at which Model Y will come to a stop. Drive attentively and always stay prepared to use the brake pedal to stop as appropriate based on traffic and road conditions.

    WARNING: Forward Collision Warning and Automatic Emergency Braking do not operate when driving at very low speeds. Do not rely on these features to warn you, or to prevent or reduce the impact of a collision.

    NOTE: Your chosen setting is retained in your Driver Profile until you manually change it.


    Parking Brake

    To engage the parking brake, touch Controls > Safety & Security > Parking Brake and follow the onscreen instructions. You can also engage the parking brake by pressing and holding the button on the end of the drive stalk while in Park.

    NOTE: The parking brake operates on the rear wheels only, and is independent of the pedal-operated brake system.

    WARNING: In snowy or icy conditions the rear wheels may not have sufficient traction to prevent Model Y from sliding down a slope, particularly if not using winter tires. Avoid parking on hills in snowy or icy conditions. You are always responsible for parking safely.

    WARNING: Your Model Y may display an alert if the road is too steep to safely park on, or if the parking brakes are not properly engaged. These alerts are for guidance purposes only and are not a substitute for the driver’s judgment of safe parking conditions, including specific road or weather conditions. Do not depend on these alerts to determine whether or not it is safe to park at any location. You are always responsible for parking safely.

    When you manually apply the parking brake using the touchscreen (Controls > Safety & Security > Parking Brake), or by pressing and holding the button on the end of the drive stalk when in Park, the red parking brake indicator (P) PARK lights up on the touchscreen.

    If the parking brake experiences an electrical issue, the amber parking brake indicator (P) lights up and a fault message displays at the top of the touchscreen.

    CAUTION: In the unlikely event that Model Y loses electrical power, you cannot access the touchscreen and are therefore unable to release the parking brake without first jump starting Model Y.


    Brake Wear

    Model Y brake pads are equipped with wear indicators. A wear indicator is a thin metal strip attached to the brake pad that squeals as it rubs against the rotor when the pad wears down. This squealing sound indicates that the brake pads have reached the end of their service life and require replacement. To replace the brake pads, contact Tesla Service.

    Brakes must be periodically inspected visually by removing the tire and wheel. Additionally, Tesla recommends cleaning and lubricating the brake calipers every year or 12,500 miles (20,000 km) if in an area where roads are salted during winter months.

    WARNING: Neglecting to replace worn brake pads damages the braking system and can result in a braking hazard.