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443 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■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.
●Vehicles with compact spare tire: Do not tow if your vehicle has a compact spare tire
installed.
●Vehicles with emergency tire puncture repair kit: Do not tow anything if a tire that has
been repaired using the emergency tire punc ture repair kit is installed. The load on
the tire may cause unexpected damage to the tire.
■When initializing the tire pressure warning system (vehicles with the tire pressure
warning system)
Do not initialize tire inflation pressure withou t first adjusting the tire inflation pressure to
the specified level. Otherwise, the tire pre ssure warning light may not come on even if
the tire inflation pressure is low, or it ma y come on when the tire inflation pressure is
actually normal.
■Caution regarding interference with electron ic devices (vehicles with the tire pres-
sure warning system featuring a tire inflation pressure display function)
●Users of any electrical medical device other than implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemakers or implantable cardioverter defibril-
lators should consult the manufacturer of the device for information about its opera-
tion under the influence of radio waves.
Radio waves could have unexpected effects on the operation of such medical
devices.
●People with implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemak-
ers or implantable cardioverter defibrillators
should not come within 450 mm (17.7 in.) of
the tire pressure warning system initiators.
The radio waves may affect the operation of
such devices.
Page 447 of 620

447
6
6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F00E_(EE)
Wheels
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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
*: Conventionally referred to as “offset”.
Lexus does not recommend using the following:
●Wheels of different sizes or types
●Used wheels
●Bent wheels that have been straightened
●Steel wheels (except for vehicles with steel spare wheel)
●Use only Lexus wheel nuts and wrenches designed for use with your alumi-
num wheels.
●When rotating, repairing or changing your tires, check that the wheel nuts are
still tight after driving 1600 km (1000 miles).
●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.
■When replacing wheels (vehicles with the tire pressure warning system)
The wheels of your vehicle are equipped with tire pressure warning valves and transmit-
ters that allow the tire pressure warning system to provide advance warning in the event
of a loss in tire inflation pressure. Whenever wheels are replaced, tire pressure warning
valves and transmitters must be installed. ( →P. 434)
If a wheel is bent, cracked or heavily corroded, it should be replaced. Other-
wise, the tire may separate from the wheel or cause a loss of handling control.
Wheel selection
Aluminum wheel precautions
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4486-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■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 a 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.
●Except for vehicles with steel spare wheel: Do not install steel wheels.
The wheel contact surface could be damaged, and the wheel could come off while
driving, which could lead to an accident resulting in death or serious injury. (except
for vehicles with steel spare wheel)
■Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air during driving, possibly causing an accident.
NOTICE
■Replacing tire pressure warning valves and transmitters (vehicles with the tire pres-
sure warning system)
●Because tire repair or replacement may affect the tire pressure warning valves and
transmitters, make sure to have tires serviced by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional or other qualified ser-
vice shop. In addition, make sure to purchase your tire pressure warning valves and
transmitters at any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
●Ensure that only genuine Lexus wheels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with non-genu-
ine wheels.
Page 467 of 620

467
7When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
7-1. Essential informationEmergency flashers...................468
If your vehicle has to be stopped in an
emergency ................................. 469 7-2. Steps to take in an emergency
If your vehicle needs to be towed................................ 470
If you think something is wrong........................................475
If a warning light turns on or a warning buzzer
sounds........................................... 476
If a warning message is displayed ................................ 482
If you have a flat tire (vehicles with spare tire)............................517
If you have a flat tire (vehicles without spare tire)................... 528
If the hybrid system will not start ............................... 543
If the shift lever cannot be shifted from P............................ 545
If the parking brake cannot be released................. 546
If the electronic key does not operate properly .....................548
If the 12-volt battery is discharged .................................. 551
If your vehicle overheats ......... 556
If the vehicle becomes stuck ............................................. 563
Page 480 of 620

4807-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caused by temperature. In this case, adjusting
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 with a tire pressure warning valve and transmit-
ter. If a tire goes flat, the tire pressure warning light will not turn off even though the flat
tire has been replaced with the spare tire.
■Conditions that the tire pressure warning system may not function properly
→P. 4 3 6
■If the tire pressure warning light frequently comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when the
power switch is turned to ON mode, have it checked by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
■Warning buzzer
In some cases, the buzzer may not be heard because of noisy place or an audio sound.
WA R N I N G
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact any authorized Lexus dealer
or repairer, or another duly qualified and equipped professional. The vehicle will
become extremely unstable during braking, and the ABS system may fail, which could
cause an accident resulting in death or serious injury.
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than us ual when operating, hold firmly and oper-
ate 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 a 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 pressure
immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If a tire is flat, change it
with the spare tire and have the flat tire repaired by the nearest any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional.
●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.
Page 517 of 620
517
7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
If you have a flat tire (vehicles with spare tire)
●Stop the vehicle on a hard, flat surface.
●Set the parking brake.
●Shift the shift lever to P.
●Stop the hybrid system.
●Turn on the emergency flashers. (
→P. 4 6 8 )
Your vehicle is equipped with a spare tire. The flat tire can be replaced with
the spare tire.
For details about tires: →P. 4 3 2
WA R N I N G
■If you have a flat tire
Do not continue driving with a flat tire.
Driving even a short distance with a flat tire can damage the tire and the wheel beyond
repair, which could result in an accident.
Before jacking up the vehicle
Page 518 of 620
5187-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
Location of the spare tire, jack and tools
Jack handle
Parking brake release tool
Screwdriver
Towing eyeletWheel nut wrench
Spare tire
Jack1
2
3
4
5
6
7
Page 520 of 620
5207-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
Remove the center luggage mat. (→P. 3 9 5 )
Remove the spacer and take out the
jack handle from the reverse side of
the center luggage mat.
Take out the jack. For tightening
For loosening
Remove the center luggage mat. ( →P. 3 9 5 )
Loosen the center fastener that
secures the spare tire.
Taking out the jack and jack handle
1
2
3
1
2
Taking out the spare tire
1
2
WA R N I N G
■When storing the spare tire
Be careful not to catch fingers or other body parts between the spare tire and the body
of the vehicle.