wheel size Lexus GS450h 2016 Owner's Manual / LEXUS 2016 GS450H OWNERS MANUAL (OM30E99U)

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4-5. Using the driving support systems
WA R N I N G
■Pre-collision braking*3
●The pre-collision braking function may not operate if certain operations are per-
formed by the driver. If the accelerator pedal is being depressed strongly or the steer-
ing wheel is being turned, the system may de termine that the driver is taking evasive
action and possibly prevent the pre-colli sion braking function from operating.
●In some situations, while the pre-collision braking function is operating, operation of
the function may be canceled if the accele rator pedal is depressed strongly or the
steering wheel is turned and the system determines that the driver is taking evasive
action.
●A large amount of braking force is applied while the pre-collision braking function is
operating. As the pre-collision braking function will be canceled after the vehicle has
been stopped for approximately 2 seconds, the driver should depress the brake
pedal as necessary.
●If the brake pedal is being depressed, the system may determine that the driver is tak-
ing evasive action and possibly delay the op eration timing of the pre-collision braking
function.
*3: Depending on the region in which the ve hicle was sold, the pre-collision braking
function may not be available.
■When to disable the pre-collision system
In the following situations, disable the syst em, as it may not operate properly, possibly
leading to an accident resultin g 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 operating and the tires are
allowed to rotate freely
●When inspecting the vehicle using a drum tester such as a chassis dynamometer or
speedometer tester, or when using an on vehicle wheel balancer
●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 stable manner, such as when the vehicle has been
in an accident or is malfunctioning
●When the vehicle is driven in a sporty manner or off-road
●When the tires are not properly inflated
●When the tires are very worn
●When tires of a size other than specified are installed
●When tire chains are installed
●When a compact spare tire or an emergency tire puncture repair kit is used

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4-5. Using the driving support systems
■Pedestrian detection function*4
*4: Depending on the region in which the vehicle was sold, the pedestrian detection func-tion may not be available.
■Cancelation of the pre-collision braking*3
●If either of the following occur while the pr e-collision braking function is operating, it
will be canceled:
• The accelerator pedal is depressed strongly.
• The steering wheel is turned sharply or abruptly.
●If the vehicle is stopped by the operation of the pre-collision braking function, the oper-
ation of the pre-collision braking function will be canceled after the vehicle has been
stopped for approximately 2 seconds.
*3: Depending on the region in which the vehi cle was sold, the pre-collision braking func-
tion may not be available.
■Conditions under which the system may operate even if there is no possibility of a colli-
sion
●In some situations such as the following, th e system may determine that there is a possi-
bility of a frontal co llision and operate.
• When passing a vehicle or pedestrian
*4
• When changing lanes while overtaking a preceding vehicle
• When overtaking a preceding vehicle that is changing lanes
The pre-collision system detects pedestrians
based on the size, profile, and motion of a
detected object. However, a pedestrian may not
be detected depending on the surrounding
brightness and the motion, posture, and angle of
the detected object, preventing the system from
operating properly. (
P. 2 3 0 )
• When overtaking a preceding vehicle that is making a left/right turn
• When passing a vehicle in an oncoming lane that is stopped to make a right/left turn

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4-5. Using the driving support systems
• 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 making 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 lowered
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or camera sensor is misaligned
●In some situations such as the following, su fficient 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
●Some pedestrians such as the following may not be detected by the radar sensor and
camera sensor, preventing the system from operating properly
*4:
• Pedestrians shorter than approximately 3. 2 ft. (1 m) or taller than approximately
6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skirt, etc.), making their sil- houette 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 vehicle
• 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 (man hole 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 object
• Pedestrians who are extremely close to the side of the vehicle (outside rear view mirror, etc.)
*4: Depending on the region in which the ve hicle was sold, the pedestrian detection
function may not be available.

GS450h_OM_OM30E99U_(U)
2714-5. Using the driving support systems
4
Driving
WA R N I N G
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded. (such as excessively
worn tires on a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■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 maintain a
safe distance from the vehicle in front of you, especially in the following situations:
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or uneven surfaces
■TRAC may not operate effectively when
Directional control and power may not be achievable while drivin g on slippery road
surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■Hill-start assist control does not operate effectively when
●Do not overly rely on the hill-start assist control. The 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 con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless 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 ap propriate to the road conditions. As these
are the systems to help ensure vehicle st ability and driving force, do not turn the
TRAC/VSC systems off unless necessary.
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire infla-
tion 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 modi fying the suspension will affect the driving
assist systems, and may caus e a system to malfunction.

GS450h_OM_OM30E99U_(U)
2754-6. Driving tips
4
Driving
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 parking brake.
The parking brake may freeze up, preventing it from being released. If necessary,
block the wheels to prevent in advertent sliding or creeping.
Vehicles with front and rear tires of the same size except for the vehicles with
LDH and 19 inch tires
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)
Cross chain
(0.16 in. [4 mm] in diameter)
Vehicles with front and rear tires of differing sizes and vehicles with LDH and
19 inch tires
Tire chains cannot be mounted.
Snow tires should be used instead.
Regulations regarding the use of tire chains vary depending on location and type
of road. Always check local regulations before installing chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
1
2
Regulations on the use of tire chains

GS450h_OM_OM30E99U_(U)
2774-6. Driving tips
4
Driving
WA R N I N G
■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 serious 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 (vehic les with front and rear tires of the same size except for
the vehicles with LDH and 19 inch tires)
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), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, ab rupt steering, sudden braking and shifting operations
that cause sudden engine braking.
●Slow down sufficiently before entering a cu rve to ensure that vehicle control is main-
tained.
●Do not use LKA (Lane-Keeping Assist) system. (if equipped)
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 attachment of snow tires affects the operation of the
tire pressure warning valves and transmitters.
■Fitting tire chains (vehicles with front and rear tires of the same size except for the
vehicles with LDH and 19 inch tires)
The tire pressure warning valves and transmitters may not function correctly when tire
chains are fitted.
■When standing the windshield wipers up
Raise the wipers in line with the windshield. ( P. 2 76 )
Failure to do so may result in dama ge to the wipers and/or the hood.

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6-3. Do-it-yourself maintenance
Rotate the tires in the order shown.
To equalize tire wear and extend tire life,
Lexus recommends that tire rotation is
carried out at the same interval as tire
inspection.
Do not fail to initialize the tire pressure
warning system after tire rotation.
Vehicles with front and rear tires of differing sizes
Tires cannot be rotated.
Your vehicle is equipped with a tire pressure warning system that uses tire pres-
sure warning valves and transmitters to detect low tire inflation pressure before
serious problems arise.
●If the tire pressure drops below a predet ermined level, the driver is warned by
the multi-information display and a warning light. ( P. 4 0 0 , 4 0 6 )
●The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( P. 9 3 )
The illustration used is intended as an
example, and may differ from the image
that is actually displayed on the multi-
information display.
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and transmitters
must also be installed.
When new tire pressure warning valves and transmitters are installed, new ID
codes must be registered in the tire pressure warning computer and the tire
pressure warning system must be initialized. Have tire pressure warning valve
and transmitter ID codes registered by your Lexus dealer. ( P. 3 6 4 )
Tire rotation
Front
Tire pressure warning system

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6-3. Do-it-yourself maintenance
◆Registering ID codes
The tire pressure warning valve and transmitter is equipped with a unique ID
code. When replacing a tire pressure warning valve and transmitter, it is nec-
essary to register the ID code. Have the ID code registered by your Lexus
dealer.
■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to expose the fabric, and
bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or location of
a cut or other damage
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered, the tire
pressure warning system will not work proper ly. After driving for about 20 minutes, the
tire pressure warning light blinks for 1 minute and stays on to indicate a system malfunc-
tion.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has seldom
or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure checks.
Make sure to check tire inflation pressure as part of your routine of daily vehicle checks.
■When rotating the tires
Make sure that the power switch is off. If the tires are rotated while the power switch is in
ON mode, the tire position information will not be updated.
If this accidentally occurs, either turn the power switch to off and then to ON mode, or
initialize the system after checking that the tire pressure is properly adjusted.
■Low profile tires (except 225/50R17 tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when compared to standard tires. Be sure to use
snow tires or tire chains on snowy and/or icy roads and drive carefully at a speed appro-
priate for road and weather conditions. ( P. 2 7 5 )

GS450h_OM_OM30E99U_(U)
3656-3. Do-it-yourself maintenance
6
Maintenance and care
■Maximum load of tire
Check that the maximum load of the replacement tire is greater than 1 /2 of the Gross
Axle Weight Ratings (GAWR) of either the front axle or the rear axle, whichever is
greater.
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway driving under
dry conditions. Since summer tires do not have the same traction performance as
snow tires, summer tires are inadequate for driving on snow-covered or icy roads. For
driving on snow-covered roads or icy roads, the use of snow tires is recommended.
When installing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to be adequate for
driving in most winter condit ions as well as for use year-round. All season tires, how-
ever, do not have adequate traction performance compared with snow tires in heavy
or loose snow. Also, all season tires fall short in acceleration and handling perfor-
mance compared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires. If
you need snow tires, select tires of the same size, construction and load capacity as the
originally installed tires. Since your vehicle has radial tires as original equipment, make
sure your snow tires also have radial cons truction. Do not install studded tires without
first checking local regulations for possible re strictions. Snow tires should be installed
on all wheels. ( P. 2 74 )
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost. For the GAWR, see the Certification Label. For
the maximum load of the tire, see the load limit
at maximum cold tire inflation pressure men-
tioned on the sidewall of the tire. ( P. 4 8 1 )

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6-3. Do-it-yourself maintenance
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheelhousings.
• If the tire inflation pressure is extremely higher than the specified level.
• If wheel without the tire pressure warning valve and transmitter are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air- port or other facility th at generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless
communication device
If tire position information is not correctl y displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could be
extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization af ter adjusting the tire inflation pressure.
Also, make sure the tires are cold before carry ing out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the power swit ch off during initialization, it is not neces-
sary to manually restart the initialization agai n, as initialization will restart automatically
the next time the power switch is turned to ON mode.
●If you accidentally perform initialization when initialization is not necessary, adjust the
tire inflation pressure to the specified level when the tires are co ld, and conduct initial-
ization again.
■When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases, the set-
tings have not been recorded and the system will not operate properly. If repeated
attempts to record tire inflation pressure settings are unsuccessful, have the vehicle
inspected by your Lexus dealer.
●The initialization message is not displayed on the multi-information display when per-
forming initialization.
●After carrying out the initialization procedure, the tire pressure warning light blinks for 1
minute then stays on after driving for 20 minutes.