2020 TOYOTA 4RUNNER brake sensor

2294-3. Operating the lights and wipers
4
Driving
4RUNNER (U)
■Daytime running light system
●The daytime running lights illuminate using the same lights as the headlight
high beam and illuminate dimmer than the headlight high beam.
● To make your vehicle more visible to other drivers during dayti me driving,
the daytime running lights turn on automatically when all of the following
conditions are met. (The daytime running lights are not designe d for use at
night.)
• The engine is running
• The parking brake is released
• The headlight switch is in the , (type A only), (type C
and D), or
* (type B and D) position
*: When the surroundings are bright
The daytime running lights remain on after they illuminate, eve n if the park-
ing brake is set again.
Type A and B: Daytime running lights can be turned off by opera ting the
switch.
● Compared to turning on the headlights, the daytime running ligh t system
offers greater durability and consumes less electricity, so it can help improve
fuel economy.
■ Headlight control sensor (if equipped)
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.

2474-5. Using the driving support systems
4
Driving
4RUNNER (U)
The pre-collision system is equipped with a sophisticated computer
that will record certain data, such as: • Accelerator status
• Brake status
• Vehicle speed
• Operation status of the pre-collision system functions
• Information (such as the dist ance and relative speed between y our
vehicle and the vehicle ahead or other objects)
• Images from the camera sensor (available only when the pre-col li-
sion braking function or the pre-collision brake assist functio n was
operating)
The pre-collision system does not record con versations, 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 recorded data to a third party exc ept:
• With the consent of the vehicle owner or with the consent of t he
lessee if the vehicle is leased
• In response to an official request by the police, a court of l aw 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 f unc-
tion is disabled, data from when the pre-collision system opera tes
will not be available.
Vehicle data recording

2544-5. Using the driving support systems
4RUNNER (U)
◆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.
◆Pre-collision brake assist
When the system determines that the possibility of a frontal colli-
sion is high, the system applies greater braking force in relat ion to
how strongly the brake pedal is depressed.
◆Pre-collision braking
When the system determines that the possibility of a frontal colli-
sion is high, the system warns the driver. If the system determ ines
that the possibility of a frontal collision is extremely high, the brakes
are automatically applied to hel p avoid the collision or reduce the
collision speed.
PCS (Pre-Collision System)
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 t he possibility of a frontal col-
lision with a vehicle or pedest rian is high, a warning operates to
urge the driver to take evasive action and the potential brake
pressure is increased to help the driver avoid the collision. If the
system determines that the possi bility 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 th e
impact of the collision.
The pre-collision system can b e disabled/enabled and the warnin g
timing can be changed. ( P. 2 5 7 )

2634-5. Using the driving support systems
4
Driving
4RUNNER (U)●
In some situations such as the following, sufficient braking fo rce 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 sli ppery sur-
face
● Some pedestrians such as the following may not be detected by t he radar
sensor and camera sensor, preventing the system from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or taller than approx-
imately 6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skir t, etc.), mak-
ing their silhouette obscure
• Pedestrians who are carrying large baggage, holding an umbrella, etc., hiding part of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller, wheelchair, bicycle or other vehi-
cle
• Groups of pedestrians which are close together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to be nearly the same color or
brightness as their surroundings
• Pedestrians near walls, fences, guardrails, or large objects
• Pedestrians who are on a metal object (manhole cover, steel plate, etc.)
on the road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly
• Pedestrians running out from behind a vehicle or a large objec t
• Pedestrians who are extremely close to the side of the vehicle (outside
rear view mirror, etc.)

2644-5. Using the driving support systems
4RUNNER (U)■
If the PCS warning light flashes or illuminates and a warning m essage is
displayed on the multi-information display
The pre-collision system may be temporarily unavailable or ther e may be a
malfunction in the system.
● In the following situations, the warning light will turn off, t he message will
disappear and the system will become operational when normal op erating
conditions return:
• When the radar sensor or camera sensor or the area around eith er sen-
sor is hot, such as in the sun
• When the radar sensor or camera sensor or the area around eith er 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. 342, 348)
• 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 the
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. 323, 324), the pre-collision brake assist and pre-col-
lision braking functions are also disabled.
● The PCS warning light will turn on and “VSC Turned Off Pre-Coll ision Brake
System Unavailable” will be displayed on the multi-information display.

2774-5. Using the driving support systems
4
Driving
4RUNNER (U)
This mode employs a radar sensor to detect the presence of vehicles
up to approximately 320 ft. (100 m) ahead, determines the curre nt
vehicle-to-vehicle following distance, and operates to maintain a suit-
able following distance from the vehicle ahead.
Note that vehicle-to-vehicle distance will close in when traveling on long
downhill slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-
vehicle distance can also be set by operating the vehicle-to-ve hicle dis-
tance switch.
Example of deceleration crui sing and follow-up cruising
When a preceding vehicle driving slower than the set speed
appears
When a vehicle is detected running ahead of you, the system automatically
decelerates your vehicle. When a greater reduction in vehicle s peed is
necessary, the system applies the brakes (the stop lights will come on at
this time). The system will respond to changes in the speed of the vehicle
ahead in order to maintain the vehicle-to-vehicle distance set by the driver.
Approach warning warns you when the system cannot decelerate su ffi-
ciently to prevent your vehicle fr om closing in on the vehicle ahead.
Example of acceleration
When there are no longer any preceding vehicles driving slower
than the set speed
The system accelerates until the set speed is reached. The syst em then
returns to constant speed cruising.
Driving in vehicle-to-vehi cle distance control mode
1
2
3

2844-5. Using the driving support systems
4RUNNER (U)■
Automatic cancelation of c onstant 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 an y other rea-
son, there may be a malfunction in the system. Contact your Toyota dealer.
■ Brake system operation sound
If the brakes are applied automatically while the vehicle is in vehicle-to-vehi-
cle distance control mode, a brake system operation sound may b e heard.
This does not indicate a malfunction.
■ Warning messages and buzzers for d ynamic radar cruise control
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 detect ing the vehicle ahead
In the case of the following and depending on the conditions, o perate 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 o f vehicles, the
approach warning ( P. 281) may not be activated.
● Vehicles that cut in suddenly
● Vehicles traveling at low speeds
● Vehicles that are not moving in the same lane
● Vehicles with small rear ends (trailers with no load on board, etc.)
● Motorcycles traveling in the same lane

2854-5. Using the driving support systems
4
Driving
4RUNNER (U)●
When water or snow thrown up by the surrounding vehicles hinders the
detecting of the sensor
■ Conditions under which the vehic le-to-vehicle distance control mode
may not function correctly
In the case of the following conditions, operate the brake peda l (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 driving on a road surrounded by a structure, such as in a tunnel or on
a bridge
● While the vehicle speed is decreasing to the set speed after th e vehicle
accelerates by depressing the accelerator pedal
●
When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
● Preceding vehicle has an extremely
high ground clearance
●When the road curves or when the
lanes are narrow
● When steering wheel operation or your
position in the lane is unstable