change LEXUS UX250H 2019 Service Manual

1864-3. Operating the lights and wipers
time the lever is pulled.
■The windshield wipers and washer can
be operated when
The power switch is in ON.
■Effects of vehicle speed on wiper opera-
tion (vehicles with rain-sensing wind-
shield wipers)
Vehicle speed affects the Intermittent wiper
interval.
■Raindrop sensor (vehicles with rain-
sensing windshield wipers)
●The raindrop sensor judges the amount
of raindrops.
An optical sensor is adopted. It may not
operate properly when sunlight from the
rising or setting of the sun intermittently
strikes the windshield, or if bugs, etc. are
present on the windshield.
●If the wiper switch is turned to the AUTO
position while the power switch is in ON,
the wipers will operate once to show that
AUTO mode is activated.
●If the temperature of the raindrop sensor
is 194°F (90°C) or higher, or 5°F (-15°C)
or lower, automatic operation may not
occur. In this case, operate the wipers in
any mode other than AUTO mode.
■If no windshield washer fluid sprays
Check that the washer nozzles are not
blocked, if there is washer fluid in the
washer fluid tank.
When the windshield wipers are not
being used, they retract to below the
hood. To enable the windshield wipers
to be lifted when parking in cold condi-
tions or when replacing a windshield
wiper insert, change the rest position of
WARNING
■Caution regarding the use of wind-
shield wipers in AUTO mode (vehi-
cles with rain-sensing windshield
wipers)
The windshield wipers may operate
unexpectedly if the sensor is touched or
the windshield is subject to vibration in
AUTO mode. Take care that your fingers,
etc. do not become caught in the wind-
shield wipers.
■Caution regarding the use of washer
fluid
When it is cold, do not use the washer
fluid until the windshield becomes warm.
The fluid may freeze on the windshield
and cause low visibility. This may lead to
an accident, resulting in death or serious
injury.
NOTICE
■When the washer fluid tank is empty
Do not operate the switch continually as
the washer fluid pump may overheat.
■When a nozzle becomes blocked
In this case, contact your Lexus dealer.
Do not try to clear it with a pin or other
object. The nozzle will be damaged.
■To prevent 12-volt battery discharge
Do not leave the wipers on longer than
necessary when the hy brid system is off.
Changing the windshield wiper
rest position/Lifting the wind-
shield wipers

1884-3. Operating the lights and wipers
Operating the switch operates
the rear wiper as follows:
1
or Off
2
or Intermittent opera-
tion
3
or Normal operation 4
Washer/wiper dual opera-
tion
Pushing the lever oper ates the wiper and
washer.
The wipers will automatically operate a
couple of times after the washer squirts.
■The rear window wiper and washer can
be operated when
The power switch is in ON.
■If no windshield washer fluid sprays
Check that the washer nozzles are not
blocked, if there is washer fluid in the
washer fluid tank.
■Reverse-linked rear window wiper func-
tion
When the shift lever is shifted to R when the
front wipers are operating, the rear window
wiper will operate once.
■Back door opening linked rear window
wiper stop function
When the rear window wi per is operating, if
the back door is opened while the vehicle is
stopped, operation of the rear window
wiper will be stopped to prevent anyone
near the vehicle from being sprayed by
water from the wiper. When the back door
is closed, wiper operation will resume.
*
*
: The setting must be customized at your Lexus dealer.
■Customization
Setting of the reverse-linked function can
be changed. (Customizable fea-
tures: P.441
Rear window wiper and
w
asher
The rear window wiper and washer
can be used by operating the lever.
NOTICE
■When the rear window is dry
Do not use the wiper, as it may damage
the rear window.
Operating the wiper lever

1944-5. Using the driving support systems
WARNING
●If the part of the windshield in front of
the front camera is fogged up or cov-
ered with condensation, or ice, use the
windshield defogger to remove the
fog, condensation, or ice. (P.277)
●If water droplets cannot be properly
removed from the area of the wind-
shield in front of the front camera by
the windshield wipers, replace the
wiper insert or wiper blade.
If the wiper inserts or wiper blades
need to be replaced, contact your
Lexus dealer.
●Do not attach window tint to the wind-
shield.
●Replace the windshield if it is damaged
or cracked.
If the windshield needs to be replaced,
contact your Lexus dealer.
●Do not allow liquids to contact the
front camera.
●Do not allow bright lights to shine into
the front camera.
●Do not dirty or damage the front cam-
era.
When cleaning the inside of the wind-
shield, do not allow glass cleaner to
contact the lens of the front camera.
Also, do not touch the lens.
If the lens is dirty or damaged, contact
your Lexus dealer.
●Do not subject the front camera to a
strong impact.
●Do not change the installation position
or direction of the front camera or
remove it.
●Do not disassemble the front camera.
●Do not modify any components of the
vehicle around the front camera
(inside rear view mirror, etc.) or ceiling.
●Do not attach any accessories to the
hood, front grille or front bumper that
may obstruct the front camera. Con-
tact your Lexus dealer for details.
●If a surfboard or other long object is to
be mounted on the roof, make sure
that it will not obstruct the front cam-
era.
●Do not modify the headlights or other
lights.

1974-5. Using the driving support systems
4
Driving
●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 operational.
If the message does not disappea r, contact your Lexus dealer.
When the temperature around the radar sensor is outside of the operational range, such as
when the vehicle is in the sun or in an extremely cold environment
When the front camera cannot detect objects in fr ont of the vehicle, such as when driving in
the dark, snow, or fog, or when bright lights are shining into the front camera
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 environment
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 tem-
perature around the front camera.
If a sunshade was used when the vehicle was
parked, depending on its type, the sunlight
reflected from the surface of the sunshade
may cause the temperature of the front cam-
era to become excessively high.
If the front camera is cold, such after the
vehicle is parked in an extremely cold envi-
ronment, 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.
SituationActions

1984-5. Using the driving support systems
The system can detect the following:
Vehicles
 Bicyclists
 Pedestrians
■Pre-collision warning
When the system determines that the
possibility of a frontal collision is high, a
buzzer will sound and a warning mes-
sage 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 collision is high,
the system applies greater braking
force in relation to how strongly the
brake pedal is depressed.
■Pre-collision braking
If the system determines that the possi-
bility of a frontal collision is extremely
high, the brakes are automatically
applied to help avoid the collision or
reduce the impact of the collision.
PCS (Pre-Collision System)
The pre-collision system uses a
radar sensor and front camera to
detect objects ( P.198) in front of
the vehicle. When the system
determines that the possibility of a
frontal collision with an object 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 deter-
mines that the possibility of a frontal
collision with an object is extremely
high, the brakes are automatically
applied to help avoid the collision or
help reduce the impact of the colli-
sion.
The pre-collision system can be dis-
abled/enabled and the warning tim-
ing can be changed. ( P.200)
Detectable objects
System functions
WARNING
■Limitations of the pre-collision system
●The driver is solely responsible for safe
driving. Always drive safely, taking
care to observe your surroundings. Do
not use the pre-collision system
instead of normal braking operations
under any circumstances. This system
will not prevent collisions or lessen col-
lision damage or injury in every situa-
tion. Do not overly rely on this system.
Failure to do so may lead to an acci-
dent, resulting in death or serious
injury.

1994-5. Using the driving support systems
4
Driving
WARNING
●Although this system is designed to
help avoid a collision or help reduce
the impact of the collision, its effective-
ness may change according to various
conditions, therefore the system may
not always be able to achieve the same
level of performance. Read the follow-
ing conditions carefully. Do not overly
rely on this system and always drive
carefully.
• Conditions under which the system may operate even if there is no possi-
bility of a collision: P.202
• Conditions under which the system may not operate properly: P.203
●Do not attempt to test the operation of
the pre-collision system yourself.
Depending on the objects used for
testing (dummies, cardboard objects
imitating detectable objects, etc.), the
system may not operate properly, pos-
sibly leading to an accident.
■Pre-collision braking
●When the pre-collision braking func-
tion is operating, a large amount of
braking force will be applied.
●If the vehicle is stopped by the opera-
tion of the pre-collision braking func-
tion, the pre-collision braking function
operation will be canceled after
approximately 2 seco nds. Depress the
brake pedal as necessary.
●The pre-collision braking function may
not operate if certain operations are
performed by the driver. If the acceler-
ator pedal is being depressed strongly
or the steering wheel is being turned,
the system may determine that the
driver is taking evasive action and pos-
sibly prevent the pre-collision braking
function from operating.
●In some situations, while the pre-colli-
sion braking function is operating,
operation of the function may be can-
celed if the accelerator pedal is
depressed strongly or the steering
wheel is turned and the system deter-
mines that the driver is taking evasive
action.
●If the brake pedal is being depressed,
the system may determine that the
driver is taking evasive action and pos-
sibly delay the operat ion timing of the
pre-collision braking function.
■When to disable the pre-collision sys-
tem
In the following situations, disable the
system, as it may not operate properly,
possibly leading to an accident resulting
in death or serious injury:
●When the vehicle is being towed
●When your vehicle is towing another
vehicle
●When transporting the vehicle via
truck, boat, train or similar means of
transportation
●When the vehicle is raised on a lift with
the hybrid system on and the tires are
allowed to rotate freely
●When inspecting the vehicle using a
drum tester such as a chassis dyna-
mometer or speedometer tester, or
when using an on vehicle wheel bal-
ancer
●When a strong impact is applied to the
front bumper or front grille, due to an
accident or other reasons
●If the vehicle cannot be driven in a sta-
ble manner, such as when the vehicle
has been in an accident or is malfunc-
tioning
●When the vehicle is driven in a sporty
manner or off-road
●When the tires are not properly
inflated

2004-5. Using the driving support systems
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.87) of
the multi-information display.
The system is automatically enabled each
time the power switch is turned to ON.
If the system is disabled, the PCS warn-
ing light will turn on and a message will
be displayed on the multi-information
display.
■Changing the pre-collision warn-
ing timing
The pre-collision warning timing can
be changed on ( P.87) of the
multi-information display.
The warning timing setting is retained
when the power switch is turned off. How-
ever, if the pre-collisio n system is disabled
and re-enabled, the operation timing will
return to the default setting (middle).
1Early
2
Middle
This is the default setting.
3Late
■Operational conditions
The pre-collision system is enabled and the system determines that the possibility of a frontal
collision with a detect ed object is high.
WARNING
●When the tires are very worn
●When tires of a size other than speci-
fied are installed
●When tire chains are installed
●When a compact spare tire or an
emergency tire puncture repair kit is
used
●If equipment (snow plow, etc.) that may
obstruct the radar sensor or front cam-
era is temporarily installed to the vehi-
cle
Changing settings of the pre-col-
lision system

2044-5. Using the driving support systems
bicycle ridden by more than one person,
or a uniquely shaped bicycle (bicycle with
a child seat, tandem bicycle, etc.)
• If a pedestrian/or the riding height of a bicyclist ahead is shorter than approxi-
mately 3.2 ft. (1 m) or taller than approxi-
mately 6.5 ft. (2 m)
• If a pedestrian/bicyclist is wearing over- sized clothing (a rain coat, long skirt,
etc.), making their silhouette obscure
• If a pedestrian is bending forward or squatting or bicyclist is bending forward
• If a pedestrian/bicyclist is moving fast
• If a pedestrian is pushing a stroller, wheel- chair, bicycle or other vehicle
• When driving in incl ement weather such
as heavy rain, fog, snow or a sandstorm
• When driving through steam or smoke
• When the surrounding area is dim, such
as at dawn or dusk, or while at night or in
a tunnel, making a detectable object
appear to be nearly the same color as its
surroundings
• When driving in a place where the sur-
rounding brightness changes suddenly,
such as at the entrance or exit of 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 makin g 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 front of the vehicle is raised or low- ered
• If the wheels are misaligned
• If a wiper blade is blocking the front cam- era
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is mis-
aligned●In some situations su ch 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 surface
■If VSC is disabled
●If VSC is disabled ( P.257), the pre-col-
lision brake assist and pre-collision brak-
ing 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.

2064-5. Using the driving support systems
WARNING
●When tires of a size other than speci-
fied are installed.
●Vehicle is driven in traffic lanes other
than that highways and freeways.
●During emergency towing
■Preventing LTA system malfunctions
and operations performed by mistake
●Do not modify the headlights or place
stickers, etc. on the surface of the
lights.
●Do not modify the suspension etc. If
the suspension etc. needs to be
replaced, contact your Lexus dealer.
●Do not install or place anything on the
hood or grille. Also, do not install a
grille guard (bull bars, kangaroo bar,
etc.).
●If your windshield needs repairs, con-
tact your Lexus dealer.
■Conditions in which functions may
not operate properly
In the following situations, the functions
may not operate properly and the vehicle
may depart from its lane. Drive safely by
always paying careful attention to your
surroundings and operate the steering
wheel to correct the path of the vehicle
without relying solely on the functions.
●When the follow-up cruising display is
displayed ( P.210) and the preceding
vehicle changes lanes. (Your vehicle
may follow the preceding vehicle and
also change lanes.)
●When the follow-up cruising display is
displayed ( P.210) and the preceding
vehicle is swaying. (Your vehicle may
sway accordingly and depart from the
lane.)
●When the follow-up cruising display is
displayed ( P.210) and the preceding
vehicle departs from its lane. (Your
vehicle may follow the preceding vehi-
cle and depart from the lane.)
●When the follow-up cruising display is
displayed ( P.210) and the preceding
vehicle is being driven extremely close
to the left/right lane line. (Your vehicle
may follow the preceding vehicle and
depart from the lane.)
●Vehicle is being driven around a sharp
curve.
●Objects or patterns that could be mis-
taken for white (yellow) lines are pres-
ent on the side of the road (guardrails,
curbs, reflective poles, etc.).

2074-5. Using the driving support systems
4
Driving
WARNING
●Vehicle is driven where the road
diverges, merges, etc.
●Repair marks of asphalt, white (yellow)
lines, etc. are present due to road
repair.
●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, su ch as in front of a
tollgate or checkpoint, or at an inter-
section, etc.
●The white (yellow) lines are cracked,
“Botts’ dots”, “Raised pavement
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 recognize than
lines that are white).
●The white (yellow) lines cross over a
curb, etc.
●The vehicle is driven on a bright sur-
face, such as concrete.
●If the edge of the road is not clear or
straight.
●The vehicle is driven on a surface that
is bright due to reflected light, etc.
●The vehicle is driven in an area where
the brightness change s suddenly, such
as at the entrances and exits of tunnels,
etc.
●Light from the headlights of an oncom-
ing vehicle, the sun, etc. enters the
camera.
●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 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 conditions
during driving (poor roads or road
seams).
●When driving in a tunnel or at night
with the headlights off or when a head-
light is dim due to its lens being dirty or
it being misaligned.
●The vehicle is struck by a crosswind.