2007 Lexus IS250 tire sensor

123
2-3. Operating the lights and windshield wipers
2
When driving
AFS (vehicles with discharge headlights)
AFS (Adaptive Front Lighting System) improves visibility at intersections
and on curves by automatically adjusting the level of the headlights
according to vehicle speed and the degree of the tire angle that are con-
trolled by steering input.
Operates at speeds of 6 mph (10 km/h) or higher.
■Deactivating AFS
How to switch: P. 2 2 2
The indicator turns on when the AFS is deactivated.
■Daytime running light system
To make your vehicle more visible to other drivers, the headlights turn on automati-
cally (at a reduced intensity) whenever the engine is started and the parking brake
is released. Daytime running lights are not designed for use at night.
■Headlight control sensor
The sensor may not function properly if an
object is placed on the sensor, or anything
that blocks the sensor is affixed to the wind-
shield.
Doing so interferes with the sensor detecting
the level of ambient light and may cause the
automatic headlight system to malfunction.

164
2-5. Driving information
NOTICE
■Repairing or replacing snow tires
Request repairs of and obtain replacement snow tires from Lexus dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the operation of
the tire air pressure sensor.
■Fitting tire chains
The tire air pressure sensor may not function correctly when tire chains are fitted.

223
3-5. Other interior features
3
Interior features
■Items that can be set using the satellite switches
Lexus parking assist-sensor (P. 142) ON/OFF
(if equipped)
Tire pressure warning system initialization
(P. 285)
ID code selection for tire air pressure system
(P. 2 8 6 )
AFS (Adaptive Front-lighting System) (P. 1 2 3 )
ON/OFF (if equipped)
Vehicle speed indicator ON/OFF and speed set-
ting (P. 111)
Tacho indicator ON/OFF and engine speed (rpm)
setting (P. 111)

284
4-3. Do-it-yourself maintenance
Directional tires
Tire direction marks
The tires listed below are direc-
tional. The tire sidewalls are
marked with arrows indicating the
rolling direction of the tire. If
mounted on the wrong side of the
vehicle, directional tires will per-
form poorly.
Installing tire inflation pressure sensors
When replacing tires or wheels, tire pressure sensors must also be
installed. Tire pressure sensors can be installed in any of the following
three ways:
■The tire pressure warning system
Your Lexus is equipped with a tire pressure warning system that uses
tire pressure sensors to detect low tire pressure before serious
problems arise. (P. 341, 345)
Before removing the tire from the wheel, remove the system’s tire
inflation pressure sensor. Be careful not to damage the sensor when
removing and installing the tires.
Tire size of turning directional tires
Front225/45R17 90W
225/40R18 88Y
Rear245/45R17 95W
255/40R18 95Y

285
4-3. Do-it-yourself maintenance
4
Maintenance and care
●Sensors can be removed from the old wheels and installed on the new
wheels.
●When replacing only the tire, the sensor already installed on the wheel
does not need to be replaced.
●Replacing both a wheel and its sensor.
When new tire pressure sensors are installed, new sensor ID codes must be
registered in the ECU and tire inflation pressure sensor must be initialized.
(P. 285, 286)
Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the following
circumstances:
●When the standard tire pressure changes by replacing tires or
wheels
●When tires are rotated.
●When tire pressure sensors are replaced.
●When driving with the tires inflated to a higher than standard tire
pressure.
When the tire pressure warning system is initialized, the current tire
pressure is set as the pressure benchmark.
■How to initialize the tire pressure warning system
To initialize the system, use the satellite switch. (P. 222)
Park the vehicle in safe place and turn off the engine.
Adjust the tire pressure to the specified pressure (P. 389)
Start the engine.
Make sure to adjust the tire pressure to the specified level. The tire infla-
tion pressure warning system will operate based on this pressure level.
STEP1
STEP2
STEP3

286
4-3. Do-it-yourself maintenance
The tire pressure initialization
setting display
Continue to press the  or 
switch until the initialization setting
display appears.
It may take several minutes to com-
plete the setting. Wait for several
minutes before turning the engine
switch OFF if necessary.
Recording tire pressure settings
Press the ON/OFF button for
more than 3 seconds. At this time,
the tire inflation pressure warning
indicator flashes 3 times and the
message showing that the initial
setting is complete is displayed on
the multi-information display.
Registering and selecting tire inflation pressure sensor ID codes
The tire inflation pressure sensor is equipped with a unique ID code.
To select tire inflation pressure sensor ID codes, use the satellite switch.
(P. 222)
■Registering ID codes
Two separate sets of ID codes can be registered for each vehicle. This
allows 2 separate sets of settings to be conveniently recorded for all
season and winter tires.
MAIN: The MAIN ID code is used for the factory installed tire pres-
sure sensors.
2nd: The 2nd ID code is used for tire inflation pressure sensors associ-
ated with a secondary set of tires.
Make sure to have all tire inflation pressure warning system ID codes regis-
tered by your Lexus dealer. ID codes must be reset when tires or wheels are
replaced.
STEP4

291
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■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 fatal or injury accidents.
●Do not mix tires of different makes, models, tread patterns or tread wear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix radial, bias-belted, or bias-ply tires.
●Do not mix summer, all season and winter tires.
NOTICE
■Repairing or replacing tires, wheels and sensors
●When removing the tires from the wheels, be careful not to damage the system’s
tire inflation warning sensors. Contact your Lexus dealer for details regarding the
removal and installation procedures.
●When replacing tires, make sure also to replace the tire inflation pressure sensor
grommets.
■Do not use puncture sealant sprays to repair flats
Puncture sealant sprays may damage tire inflation pressure sensors.

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.