snow chains Lexus GS450h 2015 Owner's Manual

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4-5. Using the driving support systems
CAUTION
■Situations unsuitable for LKA
Do not use LKA in any of the following situations.
Otherwise, the system may not function correctly and could result in an accident.
●When driving with snow tires, tire chains, a spare tire, or similar equipment
●When the tires have been excessively worn, or when the tire inflation pressure is
low.
●When there are objects or structures along the roadside that might be misinter-
preted as lane markers (such as guardrails, curb, reflector posts, etc.)
●When driving on snowy roads
●When pavement lane markers are difficult to see due to rain, snow, fog, sand, dirt,
etc.
●When there are visible lines on the pavement from road repairs, or if the remains
of old lane markers are still visible on the road
●When driving on slippery roads, such as those covered with rain, ice or snow
●When driving in a lane other than the driving or passing lanes on a freeway or
highway
●When driving on a road with lane closures due to maintenance, or when driving
in a temporary lane
●When emergency towing
NOTICE
■To prevent damage to or incorrect operation of the LKA system
●Do not modify the headlights or attach stickers to the surface of the lights.
●Do not modify the suspension. If any suspension part needs to be replaced, con-
tact your Lexus dealer.
●Do not install or place anything on the hood or the grille. Also, do not install a
grille guard (bull bars, kangaroo bar etc.).
●Do not modify the sun visor. If any sun visor part needs to be replaced, contact
your Lexus dealer.
●If your windshield needs repairs, contact your Lexus dealer.
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4-5. Using the driving support systems
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheat-
ing when there is frequent steering input over an extended period of time. The steer-
ing wheel may feel heavy as a result.
* Should this occur, refrain 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 the LKA (Lane-Keeping Assist) system cannot operate in this case, a warning
message will be shown on the multi-information display.
CAUTION
■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 condi-
tions
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 situa-
tions:
●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 driving on slippery
road surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■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 appropriate to the road conditions. As
these are the systems to help ensure vehicl e stability and driving force, do not turn
the TRAC/VSC systems off unless necessary.
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4-6. Driving tips
Winter driving tips
●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.
●Have the vehicle fitted with four snow tires or purchase a set of tire
chains for the rear tires.
*
Ensure that all tires are the specified size and brand, and that chains match the
size of the tires.
*: Tire chains cannot be mounted on vehicles with front and rear tires of differing
sizes and vehicles with LDH and 19-inch tires.
Carry out the necessary preparatio ns and inspections before driving
the vehicle in winter. Always drive the vehicle in a manner appropriate
to the prevailing weather conditions.
Preparation for winter
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4-6. Driving tips
XVehicles with front and rear tires of the same size except for the vehi-
cles with LDH and 19 inch tires
Use the correct tire chain size wh en 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)
XVehicles 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 loca l regulations before installing chains.
Selecting tire chains
1
2
Regulations on the use of tire chains
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3214-6. Driving tips
4
Driving
If heavy snow or icy condition is expected, shift the rest position manually.
Grip the hook section of the wiper arm firmly when shifting the wiper
position.
■To rest position
Raise the wiper in line with the
windshield.
You can stand the wipers up for the
rest position.
★ : More than 3.9 in. (10 cm)
■To retract position
Lower the wipers by pressing on
the upper part of the hook sec-
tion.
■Tire chain installation
Observe the following precautions when installing and removing chains:
●Install and remove tire chains in a safe location.
●Install tire chains on the rear tires. Do not install tire chains on the front tires.
●Install tire chains on rear tires as tightly as possible. Retighten chains after driving
1/4  1/2 mile (0.5  1.0 km).
●Install tire chains following the instructions provided with the tire chains.
Shifting the windshield wiper position
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4-6. Driving tips
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 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.
●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 30 mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, abrupt steering, sudden braking and shifting opera-
tions that cause sudden engine braking.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
●Do not use LKA (Lane-Keeping Assist) system.
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3234-6. Driving tips
4
Driving
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. 3 2 1 )
Failure to do so may result in damage to the wipers and/or the hood.
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6-3. Do-it-yourself maintenance
■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.
■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, which-
ever 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 perfor-
mance 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 ade-
quate for driving in most winter conditions as well as for use year-round. All season
tires, however, do not have adequate traction performance compared with snow
tires in heavy or loose snow. Also, all season tires fall short in acceleration and han-
dling performance 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 equip-
ment, make sure your snow tires also have radial construction. Do not install stud-
ded tires without first checking local regulations for possible restrictions. Snow
tires should be installed on all wheels. (→P. 3 1 8 )
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the load
limit at maximum cold tire inflation pressure
mentioned on the sidewall of the tire.
(
→ P. 5 8 7 )
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4496-3. Do-it-yourself maintenance
6
Maintenance and care
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■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.
• 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 electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wire- less 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 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 after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire inflation
pressure adjustment.
●If you have accidentally turned the power switch off during initialization, it is not
necessary to press the reset switch again as initialization will restart automatically
when the power switch has been turned to ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust
the tire inflation pressure to the specified level when the tires are cold, and conduct
initialization again.
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5517-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)
7
When trouble arises
■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. 5 8 2 )
■When using the compact spare tire
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 compared to
when driving with standard tires.
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on one of the front wheels of the vehicle. Perform 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.
1
2
3
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