3894-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
In low temperatures, the screen may darken or the image may become
faint. The image could distort when the vehicle is moving, or you may
become unable to see the image on the screen. Be sure to check direct
visually and with mirror all around the vehicle before proceeding.
If the tire sizes are changed, the position of the guide lines displayed on
the screen may change.
The camera uses a special lens. The distances between objects and pedes-
trians that appear in the image displayed on the screen will differ from the
actual distances. (P. 381)
When using the perpendicular parking assist screen
Estimated course line display mode: If the steering wheel is straight and the
vehicle width extension guide lines and the estimated course lines are not in
alignment, have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
When using the parallel parking assist screen
Do not use the system if the display is incorrect due to an uneven (curvy/
hilly) road or a non-straight road.
Make sure to operate the steering wheel only when the vehicle is stopped.
Be sure to check that there are no obstacles inside the blue outline.
If there are any obstacles inside the blue outline, do not use the parallel
parking assist.
When positioning the blue outline over the parking space, be sure to posi-
tion it so that the extended blue line may not cross the tire of the vehicle
parked in front of the empty space.
4054-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
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 inflation pressure level.
The ABS, TRC and VSC systems will not function correctly if different
tires are installed on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional for further information when replacing tires or
wheels.
Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will
affect the driving assist systems, and may cause a system to malfunction.
4384-6. Driving tips
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
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 at speeds in excess of the speed limit or the speed limit spec-
ified for the snow tires being used.
Use snow tires on all, not just some wheels.
Do not use LKA (Lane-Keeping Assist) system.
Driving with tire chains (vehicles 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 50 km/h (30 mph), whichever is lower.
Avoid driving on bumpy road surfaces or over potholes.
Avoid sudden acceleration, abrupt steering, sudden braking and shifting
operations that cause sudden engine braking.
Slow down sufficiently before entering a curve to ensure that vehicle con-
trol is maintained.
Do not use LKA (Lane-Keeping Assist) system.
759 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
When to replace your vehicle’s tires
Tires should be replaced if:
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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Replacing tires and wheels (vehicles with the tire pressure warning system)
If the ID code of the tire pressure warning valve and transmitter is not regis-
tered, the tire pressure warning system will not work properly. After driving
for about 10 minutes, the tire pressure warning light blinks for 1 minute and
stays on to indicate a system malfunction.
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 pres-
sure checks. Make sure to check tire inflation pressure as part of your routine
of daily vehicle checks.
When rotating the tires (vehicles with the tire pressure warning system featur-
ing a tire inflation pressure display function)
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.
7606-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
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 appropriate for road and weather conditions. (P. 436)
If the tread on snow tires wears down below 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost.
Situations in which the tire pressure warning system may not operate properly
(vehicles with the tire pressure warning system)
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 Equip-
ment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts 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 wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large
display, airport or other facility that generates strong radio waves or elec-
trical noise
• When carrying a portable radio, cellular phone, cordless phone or other
wireless communication device
Vehicles with the tire inflation pressure display function: If tire position
information is not correctly displayed due to the radio wave conditions, the
display may be corrected by driving and changing the radio wave condi-
tions.
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.
7746-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Wheels
When replacing wheels, care should be taken to ensure that they are
equivalent to those removed in load capacity, diameter, rim width
and inset
*.
Replacement wheels are available at any authorized Lexus dealer
or repairer, or another duly qualified and equipped professional.
*: Conventionally referred to as “off-
set”.
Lexus does not recommend using the following:
Wheels of different sizes or types
Used wheels
Bent wheels that have been straightened
Steel wheels (except for vehicles with a steel spare wheel)
If a wheel is bent, cracked or heavily corroded, it should be
replaced. Otherwise, the tire may separate from the wheel or cause
a loss of handling control.
Wheel selection
775
6 6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Use only Lexus wheel nuts and wrenches designed for use with
your aluminum wheels.
When rotating, repairing or changing your tires, check that the
wheel nuts are still tight after driving 1600 km (1000 miles).
Be careful not to damage the aluminum wheels when using tire
chains.
Use only Lexus genuine balance weights or equivalent and a
plastic or rubber hammer when balancing your wheels.
When replacing wheels (vehicles with the tire pressure warning system)
The wheels of your vehicle are equipped with tire pressure warning valves
and transmitters that allow the tire pressure warning system to provide
advance warning in the event of a loss in tire inflation pressure. Whenever
wheels are replaced, tire pressure warning valves and transmitters must be
installed. (P. 756)
Aluminum wheel precautions
CAUTION
When replacing wheels
Do not use wheels that are a different size from those recommended in the
Owner’s Manual, as this may result in a loss of handling control.
Never use an inner tube in a leaking wheel which is designed for a tube-
less tire. Doing so may result in an accident, causing death or serious
injury.
Do not install steel wheels.
The wheel contact surface could be damaged, and the wheel could come
off while driving, which could lead to an accident resulting in death or
serious injury. (except for vehicles with a steel spare wheel)
Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air during driving, possibly causing an
accident.
8817-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
The compact spare tire
The compact spare tire is identified by the label “TEMPORARY USE
ONLY” on the tire sidewall.
Use the compact spare tire temporarily, and only in an emergency.
Make sure to check the tire inflation pressure of the compact spare tire.
(P. 936)
When using the compact spare tire (vehicles with the tire pressure warning
system)
As the compact spare tire is not equipped with a tire pressure warning valve
and transmitter, low inflation pressure of the spare tire will not be indicated
by the tire pressure warning system. Also, if you replace the compact spare
tire after the tire pressure warning light comes on, the light remains on.
When the compact spare tire is equipped
The vehicle becomes lower when driving with the compact spare tire com-
pared to when driving with standard tires.
If you have a flat rear tire on a road covered with snow or ice (vehicles with
front and rear tires of the same size and compact spare tire only)
Install the compact spare tire on one of the front wheels of the vehicle. Per-
form the following steps and fit tire chains to the rear tires:
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehicle.
Fit tire chains to the rear tires.
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