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■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to expose the fabric, and
bulges indicating internal damage.
●A tire goes flat repeatedly or cannot be properly repaired due to the size or location of
a cut or other damage.
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered, the tire
pressure warning system will not work proper ly. After driving for about 20 minutes, the
tire pressure warning light blinks for 1 minu te and stays on to indicate a system malfunc-
tion.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has seldom
or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning syst em does not replace routine tire inflation pressure checks.
Make sure to check tire inflat ion pressure as part of your routine of daily vehicle checks.
■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, whichever is
greater.
For the GAWR, see the Certification Label. For
the maximum load of the tire, see the load limit
at maximum cold tire inflation pressure men-
tioned on the sidewall of the tire. ( P. 594)
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4926-3. Do-it-yourself maintenance
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■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• If a window tint that affects th e radio wave signals is installed.
• If there is a lot of snow or ice on the vehi cle, particularly around the wheels or wheel
housings.
• If the tire inflation pressure is extr emely higher than the specified level.
• If wheel without the tire pressure warning valve and transmitter is used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-
port or other facility that generates st rong radio waves or electrical noise.
• When carrying a portable radio, cellular phone, cordless phone or other wireless
communication device.
If tire position information is not correctl y displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could be
extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization afte r adjusting the tire inflation pressure.
Also, make sure the tires are cold before carryi ng out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the power switch off during initialization, it is not neces-
sary to press the reset switch again as initialization will restart automatically when the
power switch has been turned to ON mode for the next time.
●If you accidentally press the re set switch when initialization is not necessary, adjust the
tire inflation pressure to the specified leve l when the tires are cold, and conduct initial-
ization again.
●While the position of each tire is being de termined and the inflation pressures are not
being displayed on the multi-info rmation display, if the inflation pressure of a tire drops,
the tire pressure warning light will come on.
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4936-3. Do-it-yourself maintenance
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Maintenance and care
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■Warning performance of the tire pressure warning system
The warning of the tire pressure warning system will change in accordance with the con-
ditions under which it was init ialized. For this reason, the system may give a warning even
if the tire pressure does not reach a low enough level, or if the pressure is higher than the
pressure that was adjusted to when the system was initialized.
■When initialization of the tire pressure warning system has failed
Initialization may take longer to complete if the vehicle is driven on an unpaved road.
When performing initialization, drive on a pa ved road if possible. Depending on the driv-
ing environment and condition of the tires, initialization will be completed in approxi-
mately 10 to 30 minutes. If initialization is not complete after driving approximately 10 to
30 minutes, continue driving for a while.
If the inflation pressure of each tire is not displayed after driving for approximately 1 hour,
perform the following procedure.
●Park the vehicle in a safe place for approxim ately 20 minutes. Then drive straight (with
occasional left and right turns) at appr oximately 25 mph (40 km/h) or more for
approximately 10 to 30 minutes.
However, in the following situations, the tire inflation pressure will not be recorded and
the system will not operate proper ly. Perform initialization again.
●When operating the tire pressure warning reset switch, the tire pressure warning light
does not blink 3 times.
●After performing initia lization, the tire pressure warning light blinks for 1 minute then
stays on while driving.
If the inflation pressure of each tire is still not displayed, have the vehicle inspected by
your Lexus dealer.
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4956-3. Do-it-yourself maintenance
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Maintenance and care
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WARNING
■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 han-
dling 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 snow 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.
●Do not tow if your vehicle has a compact spare tire installed.
■When initializing the tire pressure warning system
Do not initializing tire inflatio n pressure 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 trans-
mitters may be damaged if not handled correctly.
●Make sure to install the tire valve caps. If the tire valve caps are not installed, water
could enter the tire pressure warning valves and the tire pressure warning valves
could be bound.
●When replacing tire valve caps, do not use tire valve caps other than those specified.
The cap may become stuck.
■To avoid damage to the tire pressu re warning valves and transmitters
When a tire is repaired with liquid sealants, the tire pressure warning valve and trans-
mitter may not operate properly. If a liquid sealant is used, contact your Lexus dealer or
other qualified service shop as soon as possi ble. Make sure to replace the tire pressure
warning valve and transmitter when replacing the tire. ( P. 488)
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
These conditions may cause lo sses in tire inflation pressure, reducing the cushioning
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.
■If tire inflation pressure of ea ch tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.
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■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may need
replacement. ( P. 513)
●If the replaced fuse blows again, have th e vehicle inspected by your Lexus dealer.
■If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
■When replacing light bulbs
Lexus recommends that you use genuine Lexus products designed for this vehicle.
Because certain bulbs are connected to circuits designed to prevent overload, nongenu-
ine parts or parts not designed for this vehicle may be unusable.
WARNING
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to th e vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage rating than that indicated, or use any other
object in place of a fuse.
●Always use a genuine Lexus fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
●Do not modify the fuses or fuse boxes.
■Fuse box near the power control unit
Never check or replace the fuses as there are high volt age parts and wiring near the
fuse box.
Doing so may cause electric shock, re sulting in death or serious injury.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your Lexus dealer as
soon as possible.
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Maintenance and care
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Adjustment bolt A
Adjustment bolt B
Make sure the vehicle has a full tank of gasoline and the area around the
headlight is not deformed.
Park the vehicle on level ground.
Sit in the driver’s seat.
Bounce the vehicle several times.
Headlight aim (vehicles with single-beam head-
lights)
Vertical movement adjusting bolts
1
2
Before checking the headlight aim
1
2
3
4
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5126-3. Do-it-yourself maintenance
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Using a Phillips-head screwdriver,
turn bolt A in either direction.
Remember the turning direction and the
number of turns.
Turn bolt B the same number of turns
and in the same direction as step .
If the headlight cannot be adjusted using
this procedure, take the vehicle to your
Lexus dealer to adjust the headlight aim.
Adjusting the headlight aim
1
2
1
Page 513 of 660
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6
Maintenance and care
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Check the wattage of the light bulb to be replaced. (P. 590)
P. 146
Light bulbs
You may replace the following bulbs by yo urself. The difficulty level of replace-
ment varies depending on the bulb. If necessary bulb replacement seems diffi-
cult to perform, contact your Lexus dealer.
For more information about replacing other light bulbs, contact your Lexus
dealer.
Preparing for light bulb replacement
Canceling the power back door system