2012 Lexus IS250 inflation pressure

429
4-3. Do-it-yourself maintenance
4
Maintenance and care
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 wh eels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.

474
5-2. Steps to take in an emergency
Warning lightWarning light/DetailsCorrection procedure
(On the center panel)
Front passenger’s seat belt
reminder light
(warning buzzer)
*2
Warns the front passenger to
fasten his/her seat belt.
Fasten the seat belt.
Tire pressure warning light
When the light comes on:
Low tire inflation pressure
such as
• Natural causes ( P. 4 76 )
• Flat tire ( P. 4 9 2 )
Adjust the tire inflation pres-
sure to the specified level.
The light will turn off after a
few minutes. In case the light
does not turn off even if the
tire inflation pressure is
adjusted, have the system
checked by your Lexus
dealer.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pres-
sure warning system
( P. 4 7 7 )
Have the system checked by
your Lexus dealer.

476
5-2. Steps to take in an emergency
■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 lamp will go off after taking several driving trips.
If the lamp does not go off even after several trips, contact your Lexus dealer as
soon as possible.
■Electric power steering warning light
When the battery is low or when the voltage drops temporarily, the electric power
steering warning light may come on.
■Front passenger detection sensor and pass enger seat belt reminder and warning
buzzer
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash and the warning buzzer to sound,
even if a passenger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pressing the
satellite switch does not turn off the tire pressure warning light.
■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 caus ed 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
The compact spare tire is not equipped wi th 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.

5
When trouble arises
477
5-2. Steps to take in an emergency
■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 freque ntly 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.
■Customization that can be configured at Lexus dealer
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features  P. 5 5 3 )

478
5-2. Steps to take in an emergency
CAUTION
■When the electric power steering warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, firmly hold 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 ti re. Check the tires. If the tire is flat,
change to the spare tire and have the flat tire repaired by the nearest Lexus
dealer.
●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.

5
When trouble arises
479
5-2. Steps to take in an emergency
CAUTION
■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 vehicl e 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.
TPMS (tire pressure warning system) malfunctions may occur for a variety of rea-
sons, including the installation of replacem ent or alternate tires or wheels on the
vehicle that prevent the TPMS (tire pressure 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.

5
When trouble arises
497
5-2. Steps to take in an emergency
■When using the compact spare tire
As the compact spare tire is not equipped with the tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be indicated. Also, if you
replace the compact spare tire after the tire pressure warning light comes on, the
light remains on.
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on the front 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 vehi-
cle.
Fit tire chains to the rear tires.
■After completing the tire change
The tire pressure warning system must be reset. ( P. 4 1 4 )
CAUTION
■Using the tire jack
Improper use of the tire jack may lead to death or serious injuries due to the vehicle
suddenly falling off the jack.
●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 the vehicle while it is supported by a jack.
●Do not start or run the engine while your vehicle is supported by the jack.
●Do not raise the vehicle while someone is in it.
●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.
STEP1
STEP2
STEP3

531
6-1. Specifications
6
Vehicle specifications
Steering
Tires and wheels■ Tires and wheels (except for compact spare)
Type A
Free playLess than 1.2 in. (30 mm)
Ti r e s i z e205/55R16 89W
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditions
Front:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
*: When driving at high speeds above 100 mph
(160 km/h), in countries where such speeds are
permitted by law, add 5.8 psi (40 kPa, 0.4 kgf/
cm
2 or bar) to the front tires and rear tires.
Never exceed the maximum cold tire inflation
pressure indicated on the tire sidewall.
Wheel size16  7JJ
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)