steering LEXUS UX250H 2019 Service Manual

2124-5. Using the driving support systems
ft. (3 m) or more.
• No system malfunctions are detected. ( P.213)
●Lane centering function
This function operates when all of the fol-
lowing conditions are met.
• LTA is turned on.
• Setting for “Steering Assist” and “Lane
Center” in of th e multi-information
display are set to “On”. ( P.87)
• This function recognizes white (yellow) lane lines or the position of a preceding
vehicle (except when the preceding vehi-
cle is small, such as a motorcycle).
• The dynamic radar cruise control with full-speed range is operating in vehicle-
to-vehicle distance control mode.
• Width of traffic lane is approximately 10 to 13 ft. (3 to 4 m).
• Turn signal lever is not operated.
• Vehicle is not being driven around a
sharp curve.
• No system malfunctions are detected.
( P.213)
• Vehicle does not acc elerate or deceler-
ate by a fixed amount or more.
• Steering wheel is not operated with a steering force level su itable for changing
lanes.
• ABS, VSC, TRAC and PCS are not oper- ating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not
displayed. ( P.212)
• The vehicle is being driven in the center
of a lane.
• Steering assist function is not operating.
■Temporary cancelation of functions
●When operation conditions are no longer
met, a function may be temporarily can-
celed. However, when the operation con-
ditions are met again, operation of the
function is automa tically restored.
(  P.211)
●If the operation conditions ( P.211) are
no longer met while the lane centering
function is operating, the steering wheel
may vibrate and the buzzer may sound to
indicate that the function has been tem-
porarily canceled. However, if the “Steer-
ing wheel vibration” customization setting is set to “On”, the system will notify
the driver by vibrating the steering wheel
instead of sounding the buzzer.
■Steering assist function/lane centering
function
●Depending on the vehicle speed, lane
departure situation, road conditions, etc.,
the driver may not feel the function is
operating or the function may not oper-
ate at all.
●The steering control of the function is
overridden by the driver’s steering wheel
operation.
●Do not attempt to test the operation of
the steering assist function.
■Lane departure alert function
●The warning buzzer may be difficult to
hear due to external noise, audio play-
back, etc. Also, it may be difficult to feel
steering wheel vibrations due to the road
conditions, etc.
●If the edge of the course* is not clear or
straight, the lane departure alert function
may not operate.
●Vehicles with Blind Spot Monitor: It may
not be possible for the system to deter-
mine if there is a danger of a collision with
a vehicle in an adjacent lane.
●Do not attempt to test the operation of
the lane departure alert function.
*: Boundary between asphalt and the side
of the road, such as grass, soil, or a curb
■Hands off steering wheel warning
In the following situations, a warning mes-
sage urging the driver to hold the steering
wheel and the symbol sh own in the illustra-
tion are displayed on the multi-information
display to warn the driver. The warning
stops when the system determines that the
driver holds the steering wheel. Always
keep your hands on the steering wheel
when using this system , regardless of warn-
ings.

2134-5. Using the driving support systems
4
Driving
●When the system determines that the
driver is driving without holding the steer-
ing wheel while the system is operating
If the driver continue s to keep their hands
off of the steering wheel, the buzzer sounds,
the driver is warned and the function is tem-
porarily canceled. This warning also oper-
ates in the same way when the driver
continuously operates the steering wheel
only a small amount.
The buzzer also sounds even if the alert
type is set to “Steering wheel vibration”.
●When the system determines that the
vehicle may not turn and instead depart
from its lane while driving around a curve
Depending on the vehicle condition and
road conditions, the warning may not oper-
ate. Also, if the system determines that the
vehicle is driving around a curve, warnings
will occur earlier than during straight-lane
driving.
●When the system determines that the
driver is driving without holding the steer-
ing wheel while the st eering wheel assist
of the steering assist function is operat-
ing.
If the driver continue s to keep their hands
off of the steering wheel and the steering
wheel assist is operating, the buzzer sounds
and the driver is warned. Each time the
buzzer sounds, the continuing time of the
buzzer becomes longer.
The buzzer also sounds even if the alert
type is set to “Steering wheel vibration”.
■Vehicle sway warning function
When the system determines that the vehi- cle is swaying while the vehicle sway warn-
ing function is operating, a buzzer sounds
and a warning message urging the driver to
rest and the symbol sh
own in the illustration
are simultaneously di splayed on the multi-
information display.
Depending on the vehicle and road condi-
tions, the warning may not operate.
■Warning message
If the following warning message is dis-
played on the multi-in formation display and
the LTA indicator illuminates in orange, fol-
low the appropriate troubleshooting proce-
dure. Also, if a different warning message is
displayed, follow the instructions displayed
on the screen.
●“LTA Unavailable”
The system is temporarily canceled due to a
malfunction in a sensor other than the front
camera. Turn the LTA system off, wait for a
little while, and then turn the LTA system
back on.
●“LTA Unavailable at Current Speed”
The function cannot be used as the vehicle
speed exceeds the LTA operation range.
Drive slower.
■Customization
Function settings can be changed.
(Customizable features: P.441)

2254-5. Using the driving support systems
4
Driving
lane
●Vehicles with small rear ends (trailers
with no load on board, etc.)
●Motorcycles traveling in the same lane
●When water or snow thrown up by the
surrounding vehicles hinders the detect-
ing of the sensor
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
●Preceding vehicle has an extremely high
ground clearance
■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 accelerator
pedal, depending on the situation) as nec-
essary.
As the sensor may not be able to correctly
detect vehicles ahead, the system may not
operate properly.
●When the road curves or when the lanes are narrow
●When steering wheel operation or your
position in the lane is unstable
●When the vehicle ahead of you deceler-
ates 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 the vehicle acceler-
ates by depressing the accelerator pedal

2564-5. Using the driving support systems
the “Eco” indicator comes on.
3Sport mode
Assists acceleration response by con-
trolling the hybrid system and steering.
Suitable for when precise handling is desir-
able, for example when driving on moun-
tain roads.
When not in Sport mode, if the driving
mode select switch is turned backward, the
“Sport” indicator comes on and the Hybrid
System Indicator changes to the tachome-
ter. ( P.78, 82)
■Operation of the air conditioning sys-
tem in Eco drive mode
Eco drive mode controls the heating/cool-
ing operations and fan speed of the air con-
ditioning system to enhance fuel efficiency.
To improve air condit ioning performance,
perform the following operations:
●Turn off eco air conditioning mode
(  P.278)
●Adjust the fan speed ( P.276, 279)
●Turn off Eco drive mode
■Automatic deactivation of Sport mode
If the power switch is turned off after driving
in Sport mode, the driving mode will be
changed to Normal mode.
■Driving mode pop-up display (vehicles
with 10.3-inch display model)
When the driving mode is changed, the
selected driving mode will be temporarily
displayed on the side display. ( P.273)
■ECB (Electronically Controlled
Brake System)
The electronically controlled system
generates braking force correspond-
ing 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 brak-
ing 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 sudden ly or turning on
slippery road surfaces
■Enhanced VSC (Enhanced Vehi-
cle Stability Control)
Provides cooperative control of the
ABS, TRAC, VSC and EPS.
Driving assist systems
To keep driving safety and perfor-
mance, the following systems oper-
ate automatically in response to
various driving situations. Be aware,
however, that these systems are
supplementary and should not be
relied upon too heavily when oper-
ating the vehicle.
Summary of the driving assist
systems

2574-5. Using the driving support systems
4
Driving
Helps to maintain directional stability
when swerving on slippery road sur-
faces by controlling steering perfor-
mance.
■Secondary Collision Brake
When the airbag sensor detects a colli-
sion, the brakes and brake lights are
automatically controlled to reduce the
vehicle speed and that helps reduce
the possibility of further damage due to
a secondary collision
■TRAC (Traction Control)
Helps to maintain drive power and pre-
vent the drive wheels from spinning
when starting the vehicle or accelerat-
ing on slippery roads
■Active Cornering Assist (ACA)
Helps to prevent the vehicle from drift-
ing to the outer side by performing
inner wheel brake control when
attempting to accelerate during cor-
nering
■Hill-start assist control
Helps to reduce the backward move-
ment 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 (AWD models)
Electronic On-Demand AWD system.
Automatically switches from front-
wheel drive to all-wheel drive (AWD)
according to the driving conditions,
helping to ensure reliable handling and stability. Examples of
conditions where
the system will switch to AWD are
when cornering, going uphill, starting
off or accelerating, and when the road
surface is slippery due to snow, rain,
etc.
■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
the switch 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 switch.
The “Traction Co ntrol Turned Off” will be
shown on the multi-information display.
Press the switch again to turn the sys-
tem back on.
■Disabling both TRAC and VSC systems
To turn the TRAC and VSC systems off,

2584-5. Using the driving support systems
press and hold the switch 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 the switch again to turn the sys-
tem back on.
*: Pre-collision brake assist and pre-colli- sion braking will also be disabled. The
PCS warning light will come on and the
message will be shown on the multi-infor-
mation display. ( P.204)
■When the message is displayed on the
multi-information display showing that
TRAC has been disabled even if the
switch has not been pressed
TRAC is temporary deactivated. If the infor-
mation continues to show, contact your
Lexus dealer.
■Operating conditions of hill-start assist
control
When the following four conditions are met,
the hill-start assist control will operate:
●The shift lever is in a position other than P
or N (when starting off forward/back-
ward on an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-
start assist control
The hill-start assist control will turn off in any
of the following situations:
●The shift lever is shifted to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●2 seconds at maximum elapsed after the
brake pedal is released
■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 indi-
cate that a malfunction has occurred in
any of these systems.
●Any of the following conditions may
occur when the above systems are oper-
ating.
None of these indicates that a malfunc-
tion 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.
●Motor sound of the brake system heard
from the front part of the vehicle when
the driver’s door is opened.
●Operating sound heard from the engine
compartment when one or two minutes
passed after the stop of the hybrid sys-
tem.
■Active Cornering Assist operation
sounds and vibrations
When Active Cornering Assist is operated,
operation sounds and vibrations may be
generated from the brake system, but this is
not a malfunction.
■EPS operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate 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

2594-5. Using the driving support systems
4
Driving
systems are turned off, automatic re-
enabling will not occur when vehicle
speed increases.
■Secondary Collision Brake operating
conditions
The vehicle speed is approximately 6 mph
(10 km/h) or more and the airbag sensor
detects a collision. (The Secondary Colli-
sion Brake will not operate when the vehicle
speed is below approximately 6 mph [10
km/h].)
■Secondary Collision Brake automatic
cancellation
The Secondary Collision Brake is automati-
cally canceled in the following situations.
●The vehicle speed drops below approxi-
mately 6 mph (10 km/h)
●A certain amount of time elapses during
operation
●The accelerator pedal is depressed a
large amount
■Operating conditions of Active Corner-
ing Assist
The system operates in the following situa-
tions.
●TRAC/VSC can operate
●The system determines that the vehicle is
drifting to the outer side when attempting
to accelerate during cornering
●The brake pedal is released
■Reduced effectiveness of the EPS sys-
tem
The effectiveness of the EPS system is
reduced to prevent the system from over-
heating when there is frequent steering
input over an extended period of time. The
steering wheel may feel heavy as a result.
Should this occur, re frain from excessive
steering input or stop the vehicle and turn
the hybrid system off. The EPS system
should return to normal within 10 minutes.
■If a message about AWD system is
shown on the multi-information display
(AWD models)
If one of the following messages is shown on
the multi-information di splay, perform each
action.
●“AWD System Overheated Switching to
2WD Mode”
The AWD system is overheating. Reduce
load on the system by stopping the vehicle
for a while or driving the vehicle at a speed
of 6 mph (10 km/h) or more. If the message
disappears, it is possible to drive the vehicle
normally.
●“AWD System Overheated 2WD Mode
Engaged”
The AWD system has been canceled and
switched to the front-wheel drive due to
overheating. Reduce load on the system by
stopping the vehicle for a while or driving
the vehicle at a speed of 6 mph (10 km/h)
or more. If the message disappears, it is
possible to drive the vehicle normally.
●“AWD System Malfunction 2WD Mode
Engaged Visit Your Dealer”
The AWD system has been stopped and
switched to the front-wheel drive due to a
malfunction. Have your vehicle inspected
by your Lexus dealer immediately.
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick road.
■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 main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations:
●When driving on dirt, gravel or snow-
covered roads

2634-6. Driving tips
4
Driving
Use fluids that are appropriate to
the prevailing outside temperatures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
Have a service technician inspect
the condition of the 12-volt battery.
 It is recommended that the vehicle is
fitted with four snow run-flat tires or
purchase a set of tire chains for the
front tires.
Ensure that all tires are the same size and
brand, and that chains match the size of the
tires.
Perform the following according to the
driving conditions:
Do not try to forcibly open a window
or move a wiper that is frozen. Pour
warm water over the frozen area to
melt the ice. Wipe away the water
immediately to prevent it from
Winter driving tips
Carry out the necessary prepara-
tions and inspections before driving
the vehicle in winter. Always drive
the vehicle in a manner appropriate
to the prevailing weather condi-
tions.
Preparation for winter
WARNING
■Driving with snow tires
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in a loss of
vehicle control and cause death or seri-
ous injury.
●Use tires of the specified size.
●Maintain the recommended level of air
pressure.
●Do not drive in excess of 75 mph (120
km/h), regardless of the type of snow
tires being used.
●Use snow tires on all, not just some
wheels.
■Driving with tire chains
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in the vehicle
being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed
limit specified for the tire chains being
used, or 30 mph (50 km/h), which-
ever is lower.
●Avoid driving on bumpy road surfaces
or over potholes.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
●Slow down sufficiently before entering
a curve to ensure that vehicle control is
maintained.
●Do not use LTA (Lane Tracing Assist).
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow
tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attach-
ment of snow tires affects the operation
of the tire pressure warning valves and
transmitters.
Before driving the vehicle

2674-6. Driving tips
4
Driving
Drive your vehicle only in areas
where off-road vehicles are permit-
ted to travel.
 Respect private property. Get
owner’s permission before entering
private property.
 Do not enter areas that are closed.
Honor gates, barriers and signs that
restrict travel.
 Stay on established roads. When
conditions are we t, driving tech-
niques should be changed or travel
delayed to prevent damage to
roads.
 AWD models: Avoid driving on very
steep, slippery roads and other sur-
faces, such as sand, where the tires
are liable to lose traction. Your vehi-
cle may not perform as well as con-
ventional AWD on-road vehicles on
these surfaces.
■Additional informatio n for off-road driv-
ing
For owners in U.S. mainland, Hawaii and
Puerto Rico:
To obtain additional information pertaining
to driving your vehicle off-road, consult the
following organizations.
●State and Local Parks and Recreation
Departments
●State Motor Vehicle Bureau
●Recreational Vehicle Clubs
●U.S. Forest Service and Bureau of Land
Management
WARNING
■Off-road driving precautions
Always observe the following precau-
tions to minimize the risk of death or seri-
ous injury or damage to your vehicle:
●Drive carefully when off the road. Do
not take unnecessary risks by driving in
dangerous places.
●Do not grip the steering wheel spokes
when driving off-road. A bad bump
could jerk the wheel and injure your
hands. Keep both hands and especially
your thumbs on the outside of the rim.
●Always check your brakes for effec-
tiveness immediately after driving in
sand, mud, water or snow.
●After driving through tall grass, mud,
rock, sand, water, et c., check that there
is no grass, bush, paper, rags, stone,
sand, etc. adhering or trapped to the
underbody. Clear of f any such matter
from the underbody. If the vehicle is
used with these materials trapped or
adhering to the underbody, a break-
down or fire could occur.
●When driving off-road or in rugged
terrain, do not drive at excessive
speeds, jump, make sharp turns, strike
objects, etc. This may cause loss of
control or vehicle rollover causing
death or serious injury. You are also
risking expensive damage to your
vehicle’s suspension and chassis.
NOTICE
■To prevent water damage
Take all necessary safety measures to
ensure that water damage to the hybrid
battery (traction battery), hybrid system
or other components does not occur.
●Water entering the engine compart-
ment may cause seve re damage to the
hybrid system. Water entering the inte-
rior may cause the hybrid battery
stowed under the re ar seats to short
circuit.

269
5
5
Interior features
Interior features
5-1. Remote TouchRemote Touch ............................ 270
5-2. Lexus Climate Concierge Lexus Climate Concierge ..... 274
5-3. Using the air conditioning system and defogger
Automatic air conditioning system ........................................................ 276
Heated steering wheel/seat heat- ers/seat ventilators ................ 286
5-4. Using the interior lights Interior lights list......................... 290
5-5. Using the storage features List of storage features............ 293
Luggage compartment features ........................................................ 296
5-6. Using the other interior features Other interior features ............ 301
Garage door opener................. 311
Compass........................................ 317