2021 TOYOTA 4RUNNER sensor

2524-5. Using the driving support systems
4RUNNER (U)If the message does not disappear, contact your Toyota dealer.
SituationActions
When the area around a cam-
era is covered with dirt, mois-
ture (fogged up, covered with
condensation, ice, etc.), or
other foreign matter
Using the wiper and A/C function,
remove the dirt and other attached mat-
ter. (
P. 342, 349)
When the temperature around
the front camera is outside of
the operational range, such as
when the vehicle is in the sun or
in an extremely cold environ-
ment
If the front camera is hot, such as after
the vehicle had been parked in the sun,
use the air conditioning system to
decrease the temperature around the
front camera.
If a sunshade was used when the vehi-
cle was parked, depending on its type,
the sunlight reflected from the surface
of the sunshade may cause the tem-
perature of the front camera to become
excessively high.
If the front camera is cold, such after the
vehicle is parked in an extremely cold
environment, use the air conditioning
system to increase the temperature
around the front camera.
The area in front of the front
camera is obstructed, such as
when the hood is open or a
sticker is attached to the part of
the windshield in front of the
front camera.
Close the hood, remove the sticker, etc.
to clear the obstruction.
When “Pre-Collision System
Unavailable” is displayed.Check whether there is attached materi-
als on the radar sensor and radar sensor
cover, and if there is, remove it.

2534-5. Using the driving support systems
4
Driving
4RUNNER (U)●
In the following situations, if the situation has changed (or the vehicle has
been driven for some time) and the normal operating conditions are
detected, the message will disappear and the system will become opera-
tional.
If the message does not disappear, contact your Toyota dealer.
• When the temperature around the radar sensor is outside of the opera- tional range, such as when the vehicle is in the sun or in an e xtremely
cold environment
• When the front camera cannot detect objects in front of the ve hicle, such
as when driving in the dark, snow, or fog, or when bright lights are shining
into the front camera
• Depending on the conditions in the vicinity of the vehicle, th e radar may
judge the surrounding environment can not be properly recognize d. In
that case, “Pre-Collision Syst em Unavailable” is displayed.

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 front camera
to detect vehicles and pedestrians in front of your vehicle. Wh en
the system determines that the possibility of a frontal collisi on
with a vehicle or pedestrian i s high, a warning operates to urg e
the driver to take evasive action and the potential brake pres-
sure is increased to help the driver avoid the collision. If the sys-
tem determines that the possibi lity of a frontal collision with a
vehicle or pedestrian is extremely high, the brakes are automat i-
cally applied to hel p avoid the collision or help reduce the
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 )

2614-5. Using the driving support systems
4
Driving
4RUNNER (U)• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When there are patterns or paint on the road or a wall that may be mis-
taken for a vehicle or pedestrian
• When driving near an object that reflects radio waves, such as a large
truck or guardrail
• When driving near a TV tower, broadcasting station, electric power plant, or other location where strong radio waves or electrical noise may be
present
■ Situations in which the syst em may not operate properly
● In some situations such as the following, a vehicle may not be detected by
the radar sensor and front camera, preventing the system from operating
properly:
• If an oncoming vehicle is approaching your vehicle
• If a vehicle ahead is a motorcycle or bicycle
• When approaching the side or front of a vehicle
• If a preceding vehicle has a small rear end, such as an unload ed truck
• If a vehicle ahead is carrying a load which protrudes past its rear bumper
• If a vehicle ahead is irregularly shaped, such as a tractor or side car
• If the sun or other light is shining directly on a vehicle ahe ad
• If a vehicle cuts in front of your vehicle or emerges from bes ide a vehicle
• When driving through or under
objects that may contact the vehicle,
such as thick grass, tree branches, or
a banner
• If a preceding vehicle has a low rear end, such as a low bed trailer
• If a vehicle ahead has extremely high ground clearance

2624-5. Using the driving support systems
4RUNNER (U)• If a vehicle ahead makes an abrupt maneuver (such as sudden sw
erving,
acceleration or deceleration)
• When suddenly cutting behind a preceding vehicle
• 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 front camera
• When the surrounding area is dim, such as at dawn or dusk, or while at
night or in a tunnel
• After the engine 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 mak ing a left/
right turn
• While driving on a curve and for a few seconds after driving o n a curve
• If your vehicle is skidding
• If the wheels are misaligned
• If a wiper blade is blocking the front camera
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or front camera is misaligned • When a vehicle ahead is not directly in front of your vehicle
• If the front of the vehicle is raised or lowered

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 front camera, preventing the system from operating p roperly:
• 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.)
■ If VSC is disabled
●If VSC is disabled ( P. 322, 323), 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.

2644-5. Using the driving support systems
4RUNNER (U)
When driving on roads with white (yellow) lines, this function alerts the
driver when the vehicle mi ght depart from its lane.
The LDA system recognizes visi-
ble white (yellow) lines with the
camera sensor on the upper por-
tion of the windshield.
LDA (Lane Depar ture Alert)
Summary of functions

2704-5. Using the driving support systems
4RUNNER (U)■
Conditions in which functions may not operate properly
In the following situations, the camera sensor may not detect w hite (yellow)
lines and various functions may not operate normally.
● There are shadows on the road that run parallel with, or cover, the white
(yellow) lines.
● The vehicle is driven in an area without white (yellow) lines, such as in front
of a tollgate or checkpoint, or at an intersection, etc.
● The white (yellow) lines are cracked, “Botts’ dots”, “Raised pa vement
marker” or stones are present.
● The white (yellow) lines cannot be seen or are difficult to see due to sand,
etc.
● The vehicle is driven on a road surface that is wet due to rain , puddles, etc.
● The traffic lines are yellow (which may be more difficult to re cognize than
lines that are white).
● The white (yellow) lines cross over a curb, etc.
● The vehicle is driven on a bright surface, such as concrete.
● The vehicle is driven on a surface that is bright due to reflec ted light, etc.
● The vehicle is driven in an area where the brightness changes s uddenly,
such as at the entrances and exits of tunnels, etc.
● Light from the headlights of an oncoming vehicle, the sun, etc. enters the
camera.
● The vehicle is driven where the road diverges, merges, etc.
● The vehicle is driven on a slope.
● The vehicle is driven on a road which tilts left or right, or a winding road.
● The vehicle is driven on an unpaved or rough road.
● The vehicle is driven around a sharp curve.
● The traffic lane is excessively narrow or wide.
● The vehicle is extremely tilted due to carrying heavy luggage or having
improper tire pressure.
● The distance to the preceding vehicle is extremely short.
● The vehicle is moving up and down a large amount due to road co nditions
during driving (poor roads or road seams).
● The headlight lenses are dirty and emit a faint amount of light at night, or the
beam axis has deviated.
● The vehicle has just changed lanes or crossed an intersection.