tire pressure Lexus IS250 2007 Audio/Video System LEXUS 2007 IS350/250 (OM53578U) Owner's Guide

293
4-3. Do-it-yourself maintenance
4
Maintenance and care
Tire inflation pressure
■Tire inflation pressure
The recommended cold tire inflation pressure and tire size is dis-
played on the tire and loading information label. (P. 389)

294
4-3. Do-it-yourself maintenance
.
■Tire inflation pressure check interval
You should check tire pressure every two weeks, or at least once a month.
Do not forget to check the spare.
■Inspection and adjustment procedure
Ti r e v a l v e
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the graduations of the gauge.
If the tire inflation pressure is not within the recommended lev-
els, adjust inflate the tire.
If you add too much air, press the center of the valve to lower.
After completing the tire inflation pressure measurement and
adjustment, apply soapy water to the valve and check for leak-
age.
Reinstall the tire valve cap.
STEP1
STEP2
STEP3
STEP4
STEP5
STEP6

295
4-3. Do-it-yourself maintenance
4
Maintenance and care
■Effects of incorrect tire inflation pressure
Driving with incorrect tire 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 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 pressure 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.

296
4-3. Do-it-yourself maintenance
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 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.

297
4-3. Do-it-yourself maintenance
4
Maintenance and care
Wheels
■When replacing wheels
The wheels of your Lexus are equipped with sensors that allow the tire pressure
warning system sensors to provide advanced warning in the event of a loss in tire
pressure. Whenever wheels are replaced, the tire inflation pressure sensors must
be switched over from the old wheels. (P. 2 8 5 )
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 offset.
Replacement wheels are available at your Lexus dealer.
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.

298
4-3. Do-it-yourself maintenance
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 serious injury or death.
NOTICE
■Replacing tire inflation pressure sensors
●Because tire repair or replacement may affect the tire pressure sensors, make
sure to have tires serviced by your Lexus dealer or other qualified service shop. In
addition, make sure to purchase your tire pressure sensors at your Lexus dealer.
●Ensure that only Genuine Lexus wheels are used on your vehicle.
Tire pressure sensors may not work properly with non-genuine wheels.

342
5-2. Steps to take in an emergency
*1:Open door warning buzzer:
P. 3 4 9
*2:Driver's and front passenger’s seat belt reminders:
The driver’s and front passenger’s seat belts reminder sounds to alert the driver
and front passenger that his or her sear belt is not fastened. The buzzer sounds
intermittently for 10 seconds after the vehicle has reached a speed of at least 12
mph (20 km/h). Then, if the seat belt is still unfastened, the buzzer will sound in a
different tone for 20 more seconds.
Warning lightWarning light/DetailsCorrection procedure
(On the center
cluster)
Front passenger’s seat belt
reminder light
(warning buzzer)
*2
Warns the front passenger to
fasten his/her seat belt.
Fasten the seat belt.
Low tire pressure warning
light
Indicates low tire pressure.Adjust the tire pressure.
A malfunction in the tire pres-
sure warning system.P. 3 4 5
Master warning light
A buzzer sounds and the
warning light comes on and
flashes to indicate that the
master warning system has
detected a malfunction.
P. 3 4 4

5
When trouble arises
345
5-2. Steps to take in an emergency
Have the vehicle inspected by your Lexus dealer immediately.
A buzzer sounds and a warning message is shown on the multi-informa-
tion display. Failing to investigate the cause of the following warnings may
lead to the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by your Lexus dealer immediately.
Wa r n i n g m e s s a g eDetails
(If equipped)
Indicates a malfunction in the AWD system.
(Flashing and then
continuously on)
Indicates a malfunction in the tire pressure warning
system. (P. 2 8 4 )
(Flashing)
Indicates a malfunction in the steering lock system.

5
When trouble arises
347
5-2. Steps to take in an emergency
■If the tire pressure warning system is inoperative
The tire pressure warning system may become inoperative in the following circum-
stances:
●The vehicle’s wheels have not been equipped with tire pressure sensors.
●The sensor batteries are dead.
●If wireless frequencies the same as those used by the sensors are being used by
other facilities or equipment in the vicinity of the vehicle.
●If snow or ice has collected on or around the wheel or wheelhouse.
●If non-genuine wheels are used on the vehicle.
●When driving with tire chains.
●If wireless devices or other equipment that operate on similar frequencies to
those used by the sensors are being used
●If the select switch is used to select the wrong set of sensors (wheels)
●If the tire pressure was not set to the specified level when the system was initial-
ized
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.

352
5-2. Steps to take in an emergency
Wa r n i n g m e s s a g eDetailsCorrection procedure
Indicates low tire pres-
sure.Check the tire pressure,
and adjust to the appropri-
ate level.
(Flashing)
(If equipped)
Indicates that the pre-
collision system is not
currently functional.
Clean the grille and the
sensor.
This message appears
when the pre-collision
system is hot. In this case,
wait until the system
cools down.
(If equipped)
Indicates that Lexus
parking assist-sensor is
dirty or covered with ice.
Clean the sensor.
(If equipped)
(Flashing)
Indicates that the radar
cruise control sensor is
dirty or covered with ice.
Clean the sensor.