2019 LEXUS UX250H warning

2494-5. Using the driving support systems
4
Driving
■The Parking Support Brake function
(static object) will operate when
The function will operate when the PKSB
OFF indicator is not illuminated or flashing
(  P.75, 76) and all of the following condi-
tions are met:
●Hybrid system output restriction control
• The Parking Support Brake is enabled.
• The vehicle speed is 10 mph (15 km/h) or less.
• There is a static object in the traveling direction of the vehicle and 6 to 13 ft. (2
to 4 m) away.
• The Parking Support Brake determines that a stronger-than-normal brake opera-
tion is necessary to avoid a collision.
●Brake control
• Hybrid system output restriction control
is operating.
• The Parking Support Brake determines that an immediate brake operation is nec-
essary to avoid a collision.
■The Parking Support Brake function
(static objects) will stop operating when
The function will stop operating if any of the
following conditions are met:
●Hybrid system output restriction control
• The Parking Support Brake is disabled.
• The system determines that the collision has become avoidable with normal brake
operation.
• The static object is no longer 6 to 13 ft. (2
to 4 m) away from the vehicle or in the
WARNING
■Handling the suspension
Do not modify the suspension, as
changes to the height or inclination of the
vehicle may prevent the sensors from
detecting objects correctly or cause the
system to not operate or operate unnec-
essarily.
■If the Parking Support Brake function
(static objects) operates unnecessar-
ily, such as at a railroad crossing
In the event that the Parking Support
Brake function (static objects) operates
unnecessarily, such as at a railroad cross-
ing, brake control w ill be canceled after
approximately 2 seconds, allowing you
to proceed forward and leave the area,
brake control can also be canceled by
depressing the brake pedal. Depressing
the accelerator pedal after brake control
is canceled will allow you to proceed for-
ward and leave the area.
■Notes when washing the vehicle
Do not apply intensive bursts of water or
steam to the sensor area.
Doing so may result in the sensor mal-
functioning.
●When using a high pressure washer to
wash the vehicle, do not spray the sen-
sors directly, as doing so may cause a
sensor to malfunction.
●When using steam to clean the vehicle,
do not direct steam too close to the
sensors as doing so may cause a sen-
sor to malfunction.
■When to disable the Parking Support
Brake (static objects)
In the following situations, disable the
Parking Support Brake (static objects) as
the system may operate even though
there is no possibility of a collision.
●When inspecting the vehicle using a
chassis roller, chassis dynamo or free
roller
●When loading the vehicle onto a boat,
truck or other transport vessel
●If the suspension has been modified or
tires of a size other than specified are
installed
●If the front of the vehicle is raised or
lowered due to the carried load
●When equipment that may obstruct a
sensor is installed, such as a towing
eyelet, bumper protector (an addi-
tional trim strip, etc.), bicycle carrier, or
snow plow
●When using an automatic car wash

2504-5. Using the driving support systems
traveling direction of the vehicle.
●Brake control
• The Parking Support Brake is disabled.
• Approximately 2 seconds have elapsed since the vehicle was stopped by brake
control.
• The brake pedal is depressed after the vehicle is stopped by brake control.
• The static object is no longer 6 to 13 ft. (2 to 4 m) away from the vehicle or in the
traveling direction of the vehicle.
■Detection range of the Parking Support
Brake function (static objects)
The detection range of the Parking Support
Brake function (static objects) differs from
the detection range of the intuitive parking
assist. ( P.236) Therefore, even if the intu-
itive parking assist detects an object and
provides a warning, the Parking Support
Brake function (static objects) may not start
operating.
■Objects that the Parking Support Brake
function (static obje cts) may not detect
The sensors may not be able to detect cer-
tain objects, such as the following:
●Pedestrian
●Cotton cloth, snow, and other materials
that are poor reflectors of ultrasonic
waves
●Objects which are not perpendicular to
the ground, are not perpendicular to the
traveling direction of the vehicle, are
uneven or are waving
●Low objects
●Thin objects such as wires, fences, ropes
and signposts
●Objects that are extremely close to the
bumper
■Situations in which the Parking Support
Brake function (stati c objects) may not
operate
When driving with the shift lever in N
■Intuitive parking assist buzzer
Regardless of whether the intuitive parking
assist function is enabled or not ( P.233),
if the Parking Support Brake function (static
objects) is enabled ( P.244), the front or
rear sensors detect an object and hybrid system output restriction control or brake
control is performed, the intuitive parking
assist buzzer will sound to notify the driver
of the approximate distance to the object.
■Situations in which the Parking Support
Brake function (static objects) may
operate even if there is no possibility of a
collision
In some situations, such as the following, the
Parking Support Brake function (static
objects) may operate even though there is
no possibility of a collision.
●Vehicle surroundings
• When driving on a narrow road
• When driving on a gravel road or in an area with tall grass
• When driving toward a banner, flag, low- hanging branch or boom barrier (such as
those used at railroad crossings, toll gates
and parking lots)
• When driving on a narrow path sur-
rounded by a structure, such as in a tun-
nel or on an iron bridge
• When parallel parking
• When there is a rut or hole in the surface
of the road
• When driving on a metal cover (grating),
such as those used for drainage ditches
• When driving on a steep slope
• If a sensor is hit by a large amount of water, such as when driving on a flooded
road
●Weather

2524-5. Using the driving support systems
*: If equipped
This function will operate in situations
such as the following if a vehicle is
detected in the traveling direction of
the vehicle.
■When reversing, a vehicle is
approaching and the brake pedal is
not depressed, or is depressed late
 P.228
■The Parking Support Brake function
(rear-crossing vehicles) will operate
when
The function will operate when the PKSB
OFF indicator is not illuminated or flashing
(  P.75, 76) and all of the following condi-
tions are met:
●Hybrid system output restriction control
• The Parking Support Brake is enabled.
• The vehicle speed is 10 mph (15 km/h) or less.
• Vehicles are approaching from the right or left at the rear of the vehicle at a travel-
ing speed of more than approximately 5
mph (8 km/h)
• The shift lever is in R.
• The Parking Support Brake determines
that a stronger than normal brake opera-
tion is necessary to avoid a collision with
Parking Support Brake func-
tion (rear-crossing vehicles)*
If a rear radar sensor detects a vehi-
cle approaching from the right or
left at the rear of the vehicle and the
system determines that the possi-
bility of a collision is high, this func-
tion will perform brake control to
reduce the likelihood of an impact
with the approaching vehicle.
Examples of function operation
Types of sensors
WARNING
■To ensure the Parking Support Brake
(rear-crossing vehicles) can operate
properly
Observe the following precautions
regarding the rear radar sensors
(  P.228). Failure to do so may cause a
sensor to not operate properly, and may
cause an accident.
●Do not modify, disassemble or paint
the sensors.
●Do not replace a rear radar sensor
with a part other than a genuine part.
●Do not damage the rear radar sensors,
and always keep the radar sensors and
their surrounding area on the bumper
clean.
■To prevent a rear radar sensor from
malfunctioning
●If the area around a rear radar sensor
is subjected to an impact, the system
may not operate properly due to a
sensor malfunction. Have the vehicle
inspected by your Lexus dealer.
●Observe the rear radar sensor han-
dling precautions. ( P.228)

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

2604-5. Using the driving support systems
WARNING
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating.
Drive the vehicle carefully in conditions
where stability and power may be lost.
■Active Cornering Assist does not
operate effectively when
●Do not rely solely upon Active Cor-
nering Assist. Active Cornering Assist
may not operate effectively when
accelerating down slopes or driving on
slippery road surfaces.
●When Active Cornering Assist fre-
quently operates, Active Cornering
Assist may temporarily stop operating
to ensure proper operation of the
brakes, TRAC, VSC.
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on the hill-start
assist control. Hill-start assist control
may not operate effectively on steep
inclines and roads covered with ice.
●Unlike the parking brake, hill-start
assist control is not intended to hold
the vehicle stationary for an extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/ABS/VSC is acti-
vated
The slip indicator light flashes. Always
drive carefully. Re ckless driving may
cause an accident. Exercise particular
care when the indicator light flashes.
■When the TRAC/VSC systems are
turned off
Be especially careful and drive at a speed
appropriate to the road conditions. As
these are the systems to help ensure
vehicle stability and driving force, do not
turn the TRAC/VSC systems off unless
necessary.
■Secondary Collision Brake
Do not overly rely on the Secondary Col-
lision Brake. This system is designed to
help reduce the possibility of further
damage due to a secondary collision,
however, that effect changes according
to various conditions. Overly relying on
the system may result in death or serious
injury.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC and VSC systems will
not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or
modifying the suspensi on will affect the
driving assist systems, and may cause a
system to malfunction.

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

2644-6. Driving tips
freezing.
 To ensure proper operation of the
climate control system fan, remove
any snow that has accumulated on
the air inlet vents in front of the
windshield.
 Check for and remove any excess
ice or snow that may have accumu-
lated on the exterior lights, vehicle’s
roof, chassis, around the tires or on
the brakes.
 Remove any snow or mud from the
bottom of your shoes before getting
in the vehicle.
Accelerate the vehicle slowly, keep a
safe distance between you and the
vehicle ahead, and drive at a reduced
speed suitable to road conditions.
 Park the vehicle and move the shift
lever to P without setting the park-
ing brake. The parking brake may
freeze up, preventing it from being
released. If the vehicle is parked
without setting the parking brake,
make sure to block the wheels.
Failure to do so may be dangerous
because it may cause the vehicle to
move unexpectedly, possibly lead-
ing to an accident.
When the parking brake is in automatic
mode, release the parking brake after shift-
ing the shift lever to P. ( P.172)
 If the vehicle is left parked with the brakes damp in cold temperatures,
there is a possibility of the brakes
freezing.
 If the vehicle is parked without set-
ting the parking brake, confirm that
the shift lever cannot be moved out
of P
*.
*: The shift lever will be locked if it is
attempted to be shifted from P to any
other position with out depressing the
brake pedal. If the shift lever can be
shifted from P, there may be a problem
with the shift lock system. Have the vehi-
cle inspected by your Lexus dealer
immediately.
Use the correct tire chain size when
mounting the tire chains. Chain size is
regulated for each tire size.
Side chain:
0.12 in. (3 mm) in diameter
0.39 in. (10 mm) in width
When driving the vehicle
When parking the vehicle
WARNING
■When parking the vehicle
When parking the vehicle without apply-
ing the parking brake, make sure to
chock the wheels. If you do not chock the
wheels, the vehicle may move unexpect-
edly, possibly result ing in an accident.
Selecting tire chains
A
B