tires Lexus IS250C 2014 Owner's Guide

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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
■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
1 Summer tiresSummer 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.
2 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 sea-
son 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 handling performance compared wi th summer tires in highway driving.
3Snow 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 capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking lo cal regulations for possible restriction.
Snow tires should be installed on all wheels. ( →P. 2 3 3 )
■Initializing the tire pressure warning system
Initialize the tire pressure warning system with the tire inflation pressure adjusted to
the specified level. 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 7 3 )

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4-3. Do-it-yourself maintenance
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Maintenance and care
IS250C/350C_U
CAUTION
■Tire pressure warning system operation
The tire pressure warning system may not provide warning immediately if a tire
bursts or if sudden air leakage occurs.
■When inspecting or replacing tires
Observe the following precautions to prevent accidents. Failure to do so may cause
damage to parts of the drive train, as well as dangerous handling characteristics,
which may lead to an accident resulting in death or serious injury.
●Do not mix tires of different makes, models or tread patterns. Also, do not mix
tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and winter tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■When initializing the tire pressure warning system
Do not press the satellite switch without first adjusting the tire inflation pressure to
the specified level. Otherwise, the tire pressure warning light may not come on
even if the tire inflation pressure is low, or it may come on when the tire inflation
pressure is actually normal.
NOTICE
■Repairing or replacing tires, wheels, tire pressure warning valves, transmitters
and tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning valves and
transmitters, contact your Lexus dealer as the tire pressure warning valves and
transmitters may be damaged if not handled correctly.
●When replacing tire valve caps, do not use tire valve caps other than those speci-
fied. The cap may become stuck.

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4-3. Do-it-yourself maintenance
IS250C/350C_U
NOTICE
■To avoid damage to the tire pressure warning valves and transmitters
When a tire is repaired with liquid sealants, the tire pressure warning valve and
transmitter may not operate properly. If a liquid sealant is used, contact your Lexus
dealer or other qualified service shop as soon as possible. Make sure to replace the
tire pressure warning valve and transmitter when replacing the tire. ( →P. 4 3 2 )
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or pot holes.
These conditions may cause losses in tire inflation pressure, reducing the cushion-
ing ability of the tires. In addition, driving on rough roads may cause damage to the
tires themselves, as well as the vehicle’s wheels and body.
■Low profile tires and wheels
Low profile tires may cause greater damage than usual to the tire wheel when
receiving impact from the road surface. Therefore pay attention to the following:
●Be sure to use proper tire inflation pressure. If tires are under-inflated, they may
be damaged more severely.
●Avoid pot holes, uneven pavement, curbs and other road hazards.
Failure to do so may lead to severe tire and wheel damage.
■If tire inflation pressures become low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

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4-3. Do-it-yourself maintenance
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Maintenance and care
IS250C/350C_U
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the following:
●Reduced fuel efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent refilling, have it checked by your Lexus dealer.
■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours and has not been driven for
more than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure
reading.
●Always use a tire pressure gauge.
The appearance of the tire can be misleading. In addition, tire inflation pressures
that are even just a few pounds off can degrade ride and handling.
●Do not bleed or reduce tire inflation press ure after driving. It is normal for the
tire inflation pressure to be higher after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is bal-
anced.

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4-3. Do-it-yourself maintenance
IS250C/350C_U
CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherwise, the following conditions may occur
and result in an accident causing death or serious injury.
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Poor sealing of the tire bead
●Wheel deformation and/or tire separation
●A greater possibility of tire damage from road hazards
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to reinstall the tire valve caps.
Without the valve caps, dirt or moisture could get into the valve and cause air leak-
age, which could result in an accident. If the caps have been lost, replace them as
soon as possible.

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4-3. Do-it-yourself maintenance
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Maintenance and care
IS250C/350C_U
Wheels
■When replacing wheels
The wheels of your Lexus are equipped with tire pressure warning valves and trans-
mitters that allow the tire pressure warning system to provide advanced warning in
the event of a loss in tire inflation pressure. Whenever wheels are replaced, the tire
pressure warning valves and transmitters must be installed. (→P. 4 3 2 )
If a wheel is bent, cracked or heavily corroded, it should be replaced. Oth-
erwise, the tire may separate from the wheel or cause loss of handling con-
trol.
■Wheel selection
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 your Lexus dealer.
*: Conventionally referred to as “offset”.
Lexus does not recommend using:
● Wheels of different sizes or types
● Used wheels
● Bent wheels that have been straightened
■ Aluminum wheel precautions
●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 1000 miles (1600 km).
● 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.

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4-3. Do-it-yourself maintenance
IS250C/350C_U
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 loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire.
Doing so may result in an accident, causing death or serious injury.
NOTICE
■Replacing tire inflation pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves
and transmitters, make sure to have tires serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase your tire pressure
warning valves and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.

When trouble arises5
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IS250C/350C_U
5-1. Essential informationEmergency flashers.............. 482
If your vehicle needs to be towed................................ 483
If you think something is wrong ...................................... 489
Fuel pump shut off system.... 490 5-2. Steps to take in an
emergency
If a warning light turns on or a warning buzzer
sounds... .................................. 491
If a warning message is displayed................................ 500
If you have a flat tire (vehicles with standard
tires) ......................................... 513
If you have a flat tire (vehicles with run-flat
tires) ........................................ 522
If the engine will not start .... 524
If the shift lever cannot be shifted from P ....................... 526
If you lose your keys .............. 527
If the electronic key does not operate properly.......... 528
If the vehicle battery is discharged ............................ 532
If your vehicle overheats ..... 536
If the vehicle becomes stuck........................................ 539
If the retractable hardtop does not close ...................... 540
If your vehicle has to be stopped in an
emergency ............................ 550

5
When trouble arises
489
5-1. Essential information
IS250C/350C_U
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature gauge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor

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5-2. Steps to take in an emergency
IS250C/350C_U
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire (vehicles with a spare tire)
The compact spare tire is not equipped with the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
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 a different set of tires has been selected using the satellite switch.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher
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 frequencies is in use in the vehicle
●If there is a lot of snow or ice on the vehicle, in particular 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 frequently comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute
when the “ENGINE START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.