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753
6 6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
Emergency measures regarding electrolyte
If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immedi-
ate medical attention. If possible, continue to apply water with a sponge or
cloth while traveling to the nearest medical facility.
If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical
attention immediately.
If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the
clothing and follow the procedure above if necessary.
If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention
immediately.
When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause
gas (hydrogen) to enter the passenger compartment, causing a fire or explo-
sion.
For replacement of the 12-volt battery, contact any authorized Lexus dealer
or repairer, or another duly qualified and equipped professional.
NOTICE
When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating.
Also, be sure all accessories are turned off.
Page 778 of 1014
7546-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indica-
tors is shown by the “TWI” or “”
marks, etc., molded on the sidewall
of each tire.
Check spare tire condition and
pressure if not rotated.
Replace or rotate tires in accordance with maintenance schedules
and treadwear.
Checking tires
1
2
3
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755 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Rotate the tires in the order shown.
To equalize tire wear and help extend tire life, Lexus recommends
that tire rotation is carried out approximately every 10000 km
(6000 miles).
Do not fail to initialize the tire pressure warning system after tire
rotation. (vehicle with the tire pressure warning system)
Tire rotation
Vehicles with front and rear
tires of the same sizeVehicles with front and rear
tires of differing sizes
FrontFront
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7566-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Your vehicle is equipped with a tire pressure warning system that
uses tire pressure warning valves and transmitters to detect low tire
inflation pressure before serious problems arise.
Vehicles without the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. (P. 834)
Vehicles with the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver
is warned by a screen display and a warning light. (P. 859)
The tire pressure detected by the tire pressure warning system
can be displayed on the multi-information display. (P. 117)
Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pressure warning system must be
initialized. Have tire pressure warning valve and transmitter ID
codes registered by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional. (P. 758)
Tire pressure warning system (if equipped)
Page 781 of 1014
757 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Initializing the tire pressure warning system
The tire pressure warning system must be initialized in the fol-
lowing circumstances:
When rotating the tires.
When the tire inflation pressure is changed such as when
changing traveling speed.
When the tire pressure warning system is initialized, the current
tire inflation pressure is set as the benchmark pressure.
How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the power switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire infla-
tion pressure level. (P. 936)
Make sure to adjust the tire pressure to the specified cold tire inflation
pressure level. The tire pressure warning system will operate based on
this pressure level.
Turn the power switch to ON mode.
1
2
3
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7586-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Press and hold the tire pres-
sure warning reset switch
until the tire pressure warn-
ing light blinks slowly 3
times.
Wait for a few minutes with the power switch in ON mode and
then turn the power switch off.
Registering ID codes
The tire pressure warning valve and transmitter is equipped with
a unique ID code. When replacing a tire pressure warning valve
and transmitter, it is necessary to register the ID code. Have the
ID code registered by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
4
5
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759 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
When to replace your vehicle’s tires
Tires should be replaced if:
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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Replacing tires and wheels (vehicles with the tire pressure warning system)
If the ID code of the tire pressure warning valve and transmitter is not regis-
tered, the tire pressure warning system will not work properly. After driving
for about 10 minutes, the tire pressure warning light blinks for 1 minute and
stays on to indicate a system malfunction.
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 system does not replace routine tire inflation pres-
sure checks. Make sure to check tire inflation pressure as part of your routine
of daily vehicle checks.
When rotating the tires (vehicles with the tire pressure warning system featur-
ing a tire inflation pressure display function)
Make sure that the power switch is off. If the tires are rotated while the power
switch is in ON mode, the tire position information will not be updated.
If this accidentally occurs, either turn the power switch to off and then to ON
mode, or initialize the system after checking that the tire pressure is properly
adjusted.
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7606-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Low profile tires (except 225/50R17 tires)
Generally, low profile tires will wear more rapidly and tire grip performance
will be reduced on snowy and/or icy roads when compared to standard tires.
Be sure to use snow tires or tire chains on snowy and/or icy roads and drive
carefully at a speed appropriate for road and weather conditions. (P. 436)
If the tread on snow tires wears down below 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost.
Situations in which the tire pressure warning system may not operate properly
(vehicles with the tire pressure warning system)
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 Equip-
ment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the
wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large
display, airport or other facility that generates strong radio waves or elec-
trical noise
• When carrying a portable radio, cellular phone, cordless phone or other
wireless communication device
Vehicles with the tire inflation pressure display function: If tire position
information is not correctly displayed due to the radio wave conditions, the
display may be corrected by driving and changing the radio wave condi-
tions.
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.