2010 Lexus HS250h tires

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When trouble arises
497
5-2. Steps to take in an emergency
■Electric power steering warning light (warning buzzer)
The electric power steering warning light comes on and the warning buzzer sounds
when the voltage is low or the voltage drops.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty? 
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose? 
If it is, tighten it securely.
The light will go off after several driving trips. 
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch will not turn off the tire pressure warning light.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural
air leaks and tire inflation pressure chan ges caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few min-
utes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning valve and trans-
mitter. If a tire goes flat, the tire pressure warning light will not turn off even though
the flat tire has been replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the tire inflatio n pressure. The tire pressure warning light
will go off after a few minutes.
■If the tire pressure warning system is not functioning
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.

498
5-2. Steps to take in an emergency
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequency is in use in the vehicle.
●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 non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used.
■If the tire pressure warning light comes on after flashing frequently for 1 minute
If the tire pressure warning light comes on after flashing frequently for 1 minute
when the “POWER” switch is turned to ON mode, have it checked by your Lexus
dealer.
■Customization that can be configured at Lexus dealer
The vehicle speed linked seat belt reminder buzzer can be disabled. 
(Customizable features P. 5 7 2 )
CAUTION
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy. 
If the steering wheel becomes heavier than usual when operating, hold firmly and
operate it using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pres-
sure immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If a tire is flat, change
it with the spare tire and have the flat tire repaired by the nearest Lexus dealer.

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When trouble arises
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5-2. Steps to take in an emergency
CAUTION
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could
lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold
and inflated to the inflation pressure re commended by the vehicle manufacturer on
the vehicle placard or tire inflation pressure label (tire and load information label).
(If your vehicle has tires of a different size than the size indicated on the vehicle
placard or tire inflation pressure label [tire and load information label], you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure
monitoring system (TPMS-tire pressure warning system) that illuminates a low tire
pressure telltale (tire pressure warning light) when one or more of your tires is sig-
nificantly under-inflated. Accordingly, when the low tire pressure telltale (tire pres-
sure warning light) illuminates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat an d can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for
proper tire maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger illumination of
the TPMS low tire pressure telltale (tire pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system)
malfunction indicator to indicate when th e system is not operating properly. The
TPMS (tire pressure warning system) malf unction indicator is combined with the
low tire pressure telltale (tire pressure warning light). When the system detects a
malfunction, the telltale will flash for approximately one minute and then remain
continuously illuminated. This sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists . When the malfunction indicator is illumi-
nated, the system may not be able to detect or signal low tire pressure as intended.

500
5-2. Steps to take in an emergency
CAUTION
TPMS (tire pressure warning system) malfunctions may occur for a variety of rea-
sons, including the installation of replacement or alternate tires or wheels on the
vehicle that prevent the TPMS (tire pres sure warning system) from functioning
properly. Always check the TPMS (tire pressure warning system) malfunction tell-
tale after replacing one or more tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow the TPMS (tire pressure warning
system) to continue to function properly.
NOTICE
■Precaution when installing a different tire
When a tire of a different specification or maker is installed, the tire pressure warn-
ing system may not operate properly.

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When trouble arises
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5-2. Steps to take in an emergency
Take out the tool tray.
Loosen the center fastener that
secur
es the spare tire.
Replacing a flat tire
Chock the tires.
Flat tireWheel chock
positions
Front
Left-
hand sideBehind the
rear right-
hand side tire
Right-
hand sideBehind the
rear left-
hand side tire
Rear
Left-
hand sideIn front of the
front right-
hand side tire
Right-
hand sideIn front of the
front left-
hand side tire

526
5-2. Steps to take in an emergency
Firmly tighten each wheel nut two
or three times in the order shown
in the illustration.
Tightening torque:
76 ft•lbf (103 N•m, 10.5 kgf•m)
Stow the flat tire, tire jack and all tools.
■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 inflatio n pressure of the compact spare tire. 
(  P. 555 )
■After completing the tire change
The tire pressure warning system must be reset. ( P.
4 3 9 )
■When using the compact spare tire
As the compact spare tire is not equipped with a tire pressure warning valve and
tr

ansmitter, low inflation pressure of the spare tire will not be indicated by the tire
pressure warning system. Also, if you repl ace the compact spare tire after the tire
pressure warning light comes on, the light remains on.
■If you have a flat front tire on a road covered with snow or ice
Install the compact spare tire on one of the rear wheels of the vehicle. Perform the
fo
llowing steps and fit tire chains to the front tires:
Replace a rear tire with the compact spare tire.
Replace the flat front tire with the tire removed from the rear of the vehi -
cle.
Fit tire chains to the front tires.

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5-2. Steps to take in an emergency
CAUTION
■Using the tire jack
Improper use of the tire jack may cause the vehicle to suddenly fall off the jack,
leading to death or serious injury.
●Do not use the tire jack for any purpose other than replacing tires or installing and
removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a flat tire.
Do not use it on other vehicles, and do no t use other tire jacks for replacing tires
on this vehicle.
●Always check that the tire jack is securely set to the jack point.
●Do not put any part of your body under th e vehicle while it is supported by the
jack.
●Do not start or run the hybrid system while your vehicle is supported by the jack.
●Do not raise the vehicle while someone is inside.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greate r than that required to replace the tire.
●Use a jack stand if it is necessary to get under the vehicle.
Take particular care when lowering the vehicle to ensure that no one working on or
near the vehicle may be injured.
■Replacing a flat tire
Observe the following precautions to reduce the risk of death or serious injury:
●Do not touch the disc wheels or the area around the brakes immediately after the
vehicle has been driven.
After the vehicle has been driven the disc wheels and the area around the brakes
will be extremely hot. Touching these areas with hands, feet or other body parts
while changing a tire, etc. may result in burns.
●Never use oil or grease on the wheel bolts or wheel nuts. 
Oil and grease may cause the wheel nuts to be excessively tightened, leading to
bolt or disc wheel damage. In addition, the oil or grease can cause the wheel nuts
to loosen and the wheel may fall off, causing a serious accident. Remove any oil or
grease from the wheel bolts or wheel nuts.

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When trouble arises
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5-2. Steps to take in an emergency
CAUTION
●Have the wheel nuts tightened with a torque wrench to 76 ft•lbf (103 N•m, 10.5
kgf•m) as soon as possible after changing wheels.
Failure to follow these precautions could cause the wheel nuts to loosen and the
tire to fall off, resulting in death or serious injury.
●When installing a tire, only use wheel nuts that have been specifically designed
for that wheel.
●If there are any cracks or deformations in the bolt screws, nut threads or bolt
holes of the wheel, have the vehicle inspected by your Lexus dealer.
Failure to follow these precautions could cause the wheel nuts to loosen and the tire
to fall off, resulting in death or serious injury.
NOTICE
■Do not drive the vehicle with a flat tire
Do not continue driving with a flat tire. 
Driving even a short distance with a flat tire can damage the tire and the wheel
beyond repair.
■Be careful when driving over bumps with the compact spare tire installed on the
vehicle.
The vehicle becomes lower when driving with the compact spare tire compared to
when driving with standard tires. Be careful when driving over uneven road sur-
faces.
■Driving with tire chains and the compact spare tire
Do not fit tire chains to the compact spare tire. 
Tire chains may damage the vehicle body and adversely affect driving performance.
■When replacing the tires
When removing or fitting the wheels, tire s or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and trans-
mitter may be damaged if not handled correctly.
■To avoid damage to the tire pressure warning valves and transmitters
Do not use liquid sealants on flat tires.