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Maintenance and care
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■Tire pressure warning system certification
MODEL/FCC IDs:
Tr a n s m i t t e r : PA X P M V 1 0 7 J
Receiver: HYQ13BCEFor vehicles sold in the U.S.A.
NOTE:
This device complies with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) this device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC WARNING:
Changes or modifications not expressly approved by the party responsible for
compliance could void the user's authority to operate the equipment. For vehicles sold in Canada
NOTE:
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interfer-
ence that may cause undesired operation of the device.
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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, ti re pressure warning valves, transmitters
and tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and
transmitter 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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Maintenance and care
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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 0 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
Wheels with profile tires like 17- and 18-inch 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 can lead to severe tire and wheel damage.
■If tire inflation pressure become low while driving
Do not continue driving, or your tires and/or wheels may be ruined.
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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 0 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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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.
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Driver’s side instrument panel
FuseAmpereCircuit
1FR P/SEAT LH30 APo w e r s e a t
2A/C7. 5 AAir conditioning system
3MIR HTR15 AOutside rear view mirror defoggers
4TV NO.110 ADisplay
5FUEL OPEN10 AFuel filler door opener
6TV NO.27. 5 A
7PSB30 A
8S/ROOF25 AMoon roof
9TA I L10 ATail lights, license plate lights, parking
lights
10PA N E L7. 5 ASwitch illumination, air conditioning
system, display, audio
11RR FOG7. 5 A
12ECU-IG LH10 A
Cruise control, air conditioning sys-
tem, power steering, rain sensor, anti-
glare inside rear view mirror, shift lock
system, moon roof, tire inflation pres-
sure warning system, VSC
13FR S/HTR LH15 ASeat heaters and ventilators
Page 450 of 578

When trouble arises5
449
IS350/250_U
5-1. Essential informationEmergency flashers............... 450
If your vehicle needs to be towed ....................................... 451
If you think something is wrong ...................................... 457
Fuel pump shut off system ..................................... 458
Event data recorder .............. 459 5-2. Steps to take in an
emergency
If a warning light turns on or a warning buzzer
sounds... ................................... 461
If a warning message is displayed................................ 470
If you have a flat tire................ 481
If the engine will not start .... 489
If the shift lever cannot be shifted from P ........................ 491
If you lose your keys .............. 492
If the electronic key does not operate properly.......... 493
If the vehicle battery is discharged ............................ 498
If your vehicle overheats ...... 501
If the vehicle becomes stuck........................................ 504
If your vehicle has to be stopped in an
emergency ............................ 506
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When trouble arises
461
IS350/250_U
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately. Continuing to drive the vehicle may be dangerous.
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
*: Parking brake engaged warning buzzer:
→P. 4 7 3
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer)*
• Low brake fluid
• Malfunction in the brake booster system
This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is fully
released the system is operating normally.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, but then turns off, this does not necessar-
ily indicate a malfunction in the system.