2018 TOYOTA PRIUS brake sensor

PRIUS_OM_OM47B89U_(U)
2514-3. Operating the lights and wipers
4
Driving
■Daytime running light system
●The daytime running lights illuminate using the same lights as the head-
lights, and illuminate dimmer than the headlights.
● To make your vehicle more visible to other drivers during daytime driving,
the daytime running lights turn on automatically when all of the following
conditions are met. (The daytime running lights are not designed for use at
night.)
• The hybrid system is operating
• The parking brake is released
• The headlight switch is in the (Canada only), , or
* position
*: When the surroundings are bright
The daytime running lights remain on after they illuminate, even if the park-
ing brake is set again.
● For the U.S.A.: Daytime running lights can be turned off by operating the
switch.
● Compared to turning on the headlights, the daytime running light system
offers greater durability and consumes less electricity, so it can help improve
fuel economy.
■ Headlight control sensor (if equipped)
■ Automatic light off system
●When the headlights come on: The headlights and tail lights turn off 30 sec-
onds after a door is opened and closed if the power switch is turned to
ACCESSORY mode or turned off. (The lights turn off immediately if on
the key is pressed after all the doors are locked.)
● When only the tail lights come on: The tail lights turn off automatically if the
power switch is turned to ACCESSORY mode or turned off and the driver’s
door is opened.
To turn the lights on again, turn the power switch to ON mode, or turn th\
e light
switch off once and then back to or . The sensor may not function properly if an
object is placed on the sensor, or anything
that blocks the sensor is affixed to the
windshield.
Doing so interferes with the sensor
detecting the level of ambient light and
may cause the automatic headlight sys-
tem to malfunction.
Air conditioning operation may also be
interrupted.

274
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
The pre-collision system is equipp ed with a sophisticated computer
that will record cert ain data, such as:
• Accelerator status
• Brake status
• Vehicle speed
• Operation status of the pre-collision system functions
• Information (such as the distanc e and relative speed between your
vehicle and the vehicle ahead or other objects)
• Images from the camera sensor (available only when the pre-colli-
sion braking function or the pre-collision brake assist function was
operating)
The pre-collision system does not record conversations, sounds or
images of the inside of the vehicle.
● Data usage
Toyota may use the data recorded in this computer to diagnose
malfunctions, conduct research and development, and improve
quality.
Toyota will not disclose the recor ded data to a third party except:
• With the consent of the vehicle owner or with the consent of the lessee if the vehicle is leased
• In response to an official request by the police, a court of law or a
government agency
• For use by Toyota in a lawsuit
• For research purposes where the data is not tied to a specific vehicle or vehicle owner
● Recorded images can be erased using a specialized device.
The image recording function can be disabled. However, if the func-
tion is disabled, data from when the pre-collision system operates
will not be available.
Vehicle data recording

281
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
4
Driving
PCS (Pre-Collision System)∗
◆Pre-collision warning
When the system determines
that the possibility of a frontal
collision is high, a buzzer will
sound and a warning message
will be displayed on the multi-
information display to urge the
driver to take evasive action.
∗: If equipped
The pre-collision system uses a radar sensor and camera sen-
sor to detect vehicles and pedest rians in front of your vehicle.
When the system determines that the possibility of a frontal col-
lision with a vehicle or pedestrian is high, a warning operates to
urge the driver to take evasive action and the potential brake
pressure is increased to help the dr iver avoid the collision. If the
system determines that the possibi lity of a frontal collision with
a vehicle or pedestrian is extremely high, the brakes are auto-
matically applied to help avoid the collision or help reduce the
impact of the collision.
The pre-collision system can be disabled/enabled and the warning
timing can be changed. ( →P. 285)

290
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
• When driving in inclement weather such as heavy rain, fog, snow or a
sandstorm
• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When driving in a place where the surrounding brightness changes sud- denly, such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun or the headlights of oncoming
traffic, shines directly into the camera sensor
• When the surrounding area is dim, such as at dawn or dusk, or while at night or in a tunnel
• After the hybrid system has started the vehicle has not been driven for a certain amount of time
• While making a left/right turn and for a few seconds after making a left/
right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or camera sensor is misaligned
● In some situations such as the following, sufficient braking force may not be
obtained, preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when
the brake parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn, improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery sur- face
• If the front of the vehicle is raised or
lowered

292
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
■If the PCS warning light flashes or illuminates and a warning message is
displayed on the mult i-information display
The pre-collision system may be tem porarily unavailable or there may be a
malfunction in the system.
● In the following situations, the warning light will turn off, the message will
disappear and the system will become operational when normal operating
conditions return:
• When the radar sensor or camera sensor or the area around either sen-
sor is hot, such as in the sun
• When the radar sensor or camera sensor or the area around either sen- sor is cold, such as in an extremely cold environment
• When a front sensor is dirty or covered with snow, etc.
• When the part of the windshield in front of the camera sensor is fogged up or covered with condensation or ice (Defogging the windshield:
→P. 520, 530)
• If the camera sensor is obstructed, such as when the hood is open or a sticker is attached to the windshield near the camera sensor
● If the PCS warning light continues to flash or remains illuminated or th\
e
warning message does not disappear even though the vehicle has returned
to normal, the system may be malfunctioning. Have the vehicle inspected by
your Toyota dealer immediately.
■ If VSC is disabled
●If VSC is disabled ( →P. 410), the pre-collision brake assist and pre-collision
braking functions are also disabled.
● The PCS warning light will turn on and “VSC Turned Off Pre-Collision Brake
System Unavailable” will be displayed on the multi-information display.

PRIUS_OM_OM47B89U_(U)
3154-5. Using the driving support systems
4
Driving
■Dynamic radar cruise control with full-speed range can be set when
● The shift position is in D.
● Vehicle speed is at or above approximately 30 mph (50 km/h).
However, when a preceding vehicle is detected, the dynamic radar cruise
control with full-speed range can be set even if the vehicle speed is below
approximately 30 mph (50 km/h).
■ Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After acceler-
ating, the set speed resumes. However, during vehicle-to-vehicle distance
control mode, the vehicle speed may decrease below the set speed in order
to maintain the distance to the preceding vehicle.
■ When the vehicle stops while follow-up cruising
●Pushing the lever up while the vehicle ahead stops will resume follow-up
cruising if the vehicle ahead starts off within approximately 3 seconds after
the switch is pressed.
● If the vehicle ahead starts off within 3 seconds after your vehicle stops, fol-
low-up cruising will be resumed.
■ Automatic cancelation of vehicle-t o-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically canceled in the fol-
lowing situations.
● Actual vehicle speed falls at or below approximately 25 mph (40 km/h) when
there are no vehicles ahead.
● The preceding vehicle leaves the lane when your vehicle is following at a
vehicle speed at or below approximately 25 mph (40 km/h). Otherwise, the
sensor can not properly detect the vehicle.
● VSC is activated.
● TRAC is activated for a period of time.
● When the VSC or TRAC system is turned off.
● The sensor cannot detect correctly because it is covered in some way.
● Pre-collision braking is activated.
● Intelligent Clearance Sonar is operated. (if equipped)
● The parking brake is operated.
● The vehicle is stopped by system control on a steep incline.

316
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
●The following are detected when the vehicle has been stopped by system
control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.
In this situation, the shift position may automatically switch to P. ( →P. 243)
If vehicle-to-vehicle distance control mode is automatically canceled for any
other reason, there may be a malfunction in the system. Contact your Toyota
dealer.
■ Automatic cancelation of co nstant speed control mode
Constant speed control mode is automatically canceled in the following situa-
tions:
● Actual vehicle speed is more than approximately 10 mph (16 km/h) below
the set vehicle speed.
● Actual vehicle speed falls below approximately 25 mph (40 km/h).
● VSC is activated.
● TRAC is activated for a period of time.
● When the VSC or TRAC system is turned off.
● Pre-collision braking is activated.
If constant speed control mode is automatically canceled for any other rea-
son, there may be a malfunction in the system. Contact your Toyota dealer.
■ Warning messages and buzzers for dy namic radar cruise control with
full-speed range
Warning messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. If a warning message
is shown on the multi-information display, read the message and follow the
instructions.
■ When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the
brake pedal when deceleration of the system is insufficient or operate the
accelerator pedal when acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning ( →P. 313) may not be activated.
● Vehicles that cut in suddenly
● Vehicles traveling at low speeds
● Vehicles that are not moving in the same lane

318
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
■Conditions under which the vehicle -to-vehicle distance control mode
may not function correctly
In the case of the following conditions, operate the brake pedal (or accelera-
tor pedal, depending on the situation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system
may not operate properly.
● When the vehicle ahead of you decelerates suddenly
●
When the road curves or when the lanes
are narrow
● When steering wheel operation or your
position in the lane is unstable