Toyota Prius: Driving assist systems

The Toyota Prius 2024-2025 is equipped with advanced driving assist systems designed to enhance safety and convenience. These typically include:

1. Toyota Safety Sense: Standard across many Toyota models, this suite includes features like Pre-Collision System with Pedestrian Detection, Lane Departure Alert with Steering Assist, Dynamic Radar Cruise Control, and Automatic High Beams.

2. Parking Support Brake (PKSB): Helps prevent collisions while parking by detecting static objects and automatically applying brakes if necessary.

3. Intuitive Parking Assist: Uses sensors to detect obstacles around the vehicle, providing visual and audible alerts to aid in parking maneuvers.

4. Advanced Park System: Assists in parallel and perpendicular parking by providing guidance through cameras and sensors, and automatically adjusting the vehicle's position if needed.

These systems collectively contribute to a safer driving experience by providing assistance in various scenarios, from highway driving to parking in tight spaces.

To keep driving safety and performance, the following systems operate automatically in response to various driving situations. Be aware, however, that these systems are supplementary and should not be relied upon too heavily when operating the vehicle.

Summary of the driving assist systems

ECB (Electronically Controlled Brake System)

The electronically controlled system generates braking force corresponding to the brake operation

ABS (Anti-lock Brake System)

Helps to prevent wheel lock when the brakes are applied suddenly, or if the brakes are applied while driving on a slippery road surface

Brake assist

Generates an increased level of braking force after the brake pedal is depressed when the system detects a panic stop situation

VSC (Vehicle Stability Control)

Helps the driver to control skidding when swerving suddenly or turning on slippery road surfaces.

Enhanced VSC (Enhanced Vehicle Stability Control)

Provides cooperative control of the ABS, TRAC, VSC and EPS.

Helps to maintain directional stability when swerving on slippery road surfaces by controlling steering performance.

TRAC (Traction Control)

Helps to maintain drive power and prevent the drive wheels from spinning when starting the vehicle or accelerating on slippery roads

Active Cornering Assist (ACA)

Helps to prevent the vehicle from drifting to the outer side by performing inner wheel brake control when attempting to accelerate while turning

Hill-start assist control

Helps to reduce the backward movement of the vehicle when starting on an uphill

EPS (Electric Power Steering)

Employs an electric motor to reduce the amount of effort needed to turn the steering wheel.

E-Four (Electronic On- Demand AWD system) (AWD models)

Automatically controls the drive system such as to front-wheel drive or AWD (all wheel drive) according to various running conditions including normal driving, during cornering, on a uphill, when starting off, during acceleration, on a slippery roads due to snow or rain, thus contributing to stable operability and driving stability.

The Secondary Collision Brake

When the SRS airbag sensor detects a collision and the system operates, the brakes and brake lights are automatically controlled to reduce the vehicle speed and help reduce the possibility of further damage due to a secondary collision.

When the TRAC/VSC/ABS systems are operating

The slip indicator light will flash while the TRAC/VSC/ABS systems are operating.

 

Disabling the TRAC system

If the vehicle gets stuck in mud, dirt or snow, the TRAC system may reduce power from the hybrid system to the wheels.

Pressing to turn the system off may make it easier for you to rock the vehicle in order to free it.

To turn the TRAC system off, quickly press and release .

The "Traction Control Turned OFF" will be shown on the multi-information display.

Press again to turn the system back on.

Turning off both TRAC and VSC systems

To turn the TRAC and VSC systems off, press and hold for more than 3 seconds while the vehicle is stopped.

The VSC OFF indicator light will come on and the "Traction Control Turned OFF" will be shown on the multi-information display.* Press again to turn the systems back on.

*: PCS (Pre-Collision System) will also be disabled (only pre-collision warning is available). The PCS warning light will come on and a message will be displayed on the multi-information display.

When the message is displayed on the multi-information display showing that TRAC has been disabled even if has not been pressed

TRAC is temporary deactivated. If the information continues to show, contact your Toyota dealer.

Operating conditions of hillstart assist control

When all of the following conditions are met, the hill-start assist control will operate:

• The shift position is in a position other than P or N (when starting off forward/backward on an upward incline)
• The vehicle is stopped
• The accelerator pedal is not depressed
• The parking brake is not engaged
• The power switch is in ON

Automatic system cancelation of hill-start assist control

The hill-start assist control will turn off in any of the following situations:

• Shift the shift position to P or N.
• The accelerator pedal is depressed
• The brake pedal is depressed and the parking brake is engaged
• A maximum of 2 seconds have elapsed after the brake pedal is released
• The power switch is turned to OFF

Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and hill-start assist control systems

• A sound may be heard from the engine compartment when the brake pedal is depressed repeatedly, when the hybrid system is started or just after the vehicle begins to move. This sound does not indicate that a malfunction has occurred in any of these systems.
• Any of the following conditions may occur when the above systems are operating. None of these indicates that a malfunction has occurred.

• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.

ECB operating sound

ECB operating sound may be heard in the following cases, but it does not indicate that a malfunction has occurred.

• Operating sound heard from the engine compartment when the brake pedal is operated.
• Operating sound heard from the engine compartment when one or two minutes passed after the stop of the hybrid system.

Active Cornering Assist operation sounds and vibrations

When the Active Cornering Assist is operated, operation sounds and vibrations may be generated from the brake system, but this is not a malfunction.

Automatic reactivation of TRAC and VSC systems

After turning the TRAC and VSC systems off, the systems will be automatically re-enabled in the following situations:

• When the power switch is turned off
• If only the TRAC system is turned off, the TRAC will turn on when vehicle speed increases If both the TRAC and VSC systems are turned off, automatic reenabling will not occur when vehicle speed increases.

Operating conditions of Active Cornering Assist

The system operates when the following occurs.

• TRAC/VSC can operate
• The driver is attempting to accelerate while turning
• The system detects that the vehicle is drifting to the outer side
• The brake pedal is released

Reduced effectiveness of the EPS system

The effectiveness of the EPS system is reduced to prevent the system from overheating when there is frequent steering input over an extended period of time. The steering wheel may feel heavy as a result. Should this occur, refrain from excessive steering input or stop the vehicle and turn the hybrid system off. The EPS system should return to normal within 10 minutes.

Secondary Collision Brake operating conditions

The system operates when the SRS airbag sensor detects a collision while the vehicle is in motion.

However, the system does not operate when the components are damaged.

Secondary Collision Brake automatic cancellation

The system is automatically canceled in any of the following situations.

• The vehicle speed drops to approximately 0 mph (0 km/h).
• A certain amount of time elapses during operation
• The accelerator pedal is depressed a large amount

If a message about AWD is shown on the multi-information display (AWD models)

Perform the following actions.

• "AWD System Overheated Switching to 2WD Mode"

AWD system is overheated. Stop the vehicle in a safe place with the hybrid system operating.* If the message disappears after a while, there is no problem. If the message remains, have the vehicle inspected by your Toyota dealer immediately.

• "AWD System Overheated 2WD Mode Engaged"

AWD system has been temporarily released and switched to frontwheel drive due to overheating.

Stop the vehicle in a safe place with the hybrid system operating.* If the message disappears after a while, AWD system will automatically recover. If the message remains, have the vehicle inspected by your Toyota dealer immediately.

• "AWD System Malfunction 2WD Mode Engaged Visit Your Dealer"

A malfunction occurs in the AWD system. Have the vehicle inspected by your Toyota dealer immediately.

*: When stopping the vehicle, do not stop the hybrid system until the display message has turned off.

WARNING

The ABS does not operate effectively when

• The limits of tire gripping performance have been exceeded (such as excessively worn tires on a snow-covered road).
• The vehicle hydroplanes while driving at high speed on wet or slick roads.

WARNING

Stopping distance when the ABS is operating may exceed that of normal conditions

The ABS is not designed to shorten the vehicle's stopping distance.

Always maintain a safe distance from the vehicle in front of you, especially in the following situations:

• When driving on dirt, gravel or snow-covered roads
• When driving with tire chains
• When driving over bumps in the road
• When driving over roads with potholes or uneven surfaces

TRAC/VSC may not operate effectively when

Directional control and power may not be achievable while driving on slippery road surfaces, even if the TRAC/VSC system is operating.

Drive the vehicle carefully in conditions where stability and power may be lost.

Active Cornering Assist does not operate effectively when

• Do not overly rely on Active Cornering Assist. Active Cornering Assist may not operate effectively when accelerating down slopes or driving on slippery road surfaces.
• When Active Cornering Assist frequently operates, Active Cornering Assist may temporarily stop operating to ensure proper operation of the brakes, TRAC and VSC.

Hill-start assist control does not operate effectively when

• Do not overly rely on hill-start assist control. Hill-start assist control may not operate effectively on steep inclines and roads covered with ice.
• Unlike the parking brake, hillstart assist control is not intended to hold the vehicle stationary for an extended period of time. Do not attempt to use hill-start assist control to hold the vehicle on an incline, as doing so may lead to an accident.

When the TRAC/ABS/VSC is activated

The slip indicator light flashes.

Always drive carefully. Reckless driving may cause an accident.

Exercise particular care when the indicator light flashes.

When the TRAC/VSC systems are turned off

Be especially careful and drive at a speed appropriate to the road conditions. As these are the systems to help ensure vehicle stability and driving force, do not turn the TRAC/VSC systems off unless necessary.

Replacing tires

Make sure that all tires are of the specified size, brand, tread pattern and total load capacity. In addition, make sure that the tires are inflated to the recommended tire inflation pressure level.

The ABS, TRAC and VSC systems will not function correctly if different tires are installed on the vehicle.

Contact your Toyota dealer for further information when replacing tires or wheels.

WARNING

Handling of tires and the suspension

Using tires with any kind of problem or modifying the suspension will affect the driving assist systems, and may cause a system to malfunction.

Secondary Collision Brake

Do not rely solely upon the Secondary Collision Brake. This system is designed to help reduce the possibility of further damage due to a secondary collision, however, that effect changes according to various conditions. Overly relying on the system may result in death or serious injury.