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6496-3. Do-it-yourself maintenance
6
Maintenance and care
CAUTION
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may pro-
duce hydrogen gas which is flammable and explosive. To reduce the risk of death
or serious injury, take the following precautions while working on or near the 12-
volt battery:
●Do not cause sparks by touching the 12-volt battery terminals with tools.
●Do not smoke or light a match near the 12-volt battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the 12-volt battery.
●Keep children away from the 12-volt battery.
■Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt bat-
tery in a garage or closed room wh ere there is insufficient ventilation.
■How to recharge the 12-volt battery
Observe the following precautions when re charging the 12-volt battery. Failure to
do so may damage the 12 -volt battery and cause de ath or serious injury.
●Slow charge: Recharge at a current of 5 A or less and make sure that the
recharging period does not exceed a total of 12 hours.
●Quick charge: Recharge at a current of 15 A or less and make sure that the
recharging period does not exceed 60 minutes.
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CAUTION
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medi-
cal 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 atten-
tion 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 imme-
diately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for this ve hicle. Failure to do so may cause gas
(hydrogen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact your Lexus dealer.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while th e hybrid system is operating. Also, be
sure all accessories are turned off.
Page 651 of 860
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GS450h_U (OM30D01U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indicators is
shown by the “TWI” or “ ” marks, etc.,
molded on the sidewall of each tire.
Check spare tire condition and pres-
sure if not rotated.
Replace or rotate tires in accord ance with maintenance schedules and
treadwear.
Checking tires
1
2
3
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6-3. Do-it-yourself maintenance
Rotate the tires in the order shown.
To equalize tire wear and extend tire
life, Lexus recommends that tire rota-
tion is carried out at the same interval
as tire inspection.
Do not fail to initialize the tire pressure
warning system after tire rotation.
Tire rotation
Front
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6536-3. Do-it-yourself maintenance
6
Maintenance and care
Your vehicle is equipped with a tire pressure warning system that uses tire
pressure warning valves and transmitters to detect low tire inflation pres-
sure 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. 715)
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. 740)
●The tire pressure detected by the tire pressure warning system can be
displayed on the multi- information display. (P. 9 7 )
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and trans-
mitters 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 pres-
sure warning valve and transmitter ID codes registered by your Lexus
dealer. ( P. 655)
◆Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the following
circumstances:
●When rotating the tires.
●When the tire inflation pressure is changed such as when changing
traveling speed or load weight.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the benchmark pressure.
Tire pressure warning system
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6-3. Do-it-yourself maintenance
■How to initialize the tire pressure warning systemPark 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 inflation
pressure level. ( P. 790)
Make sure to adjust the tire pressure to the specified cold tire inflation pres-
sure level. The tire pressure warning sy stem will operate based on this pressure
level.
Turn the power switch to ON mode.
Press and hold the tire pres-
sure warning reset switch until
the tire pressure warning light
blinks slowly 3 times.
Wait for a few minutes with the power switch in ON mode and then
turn the power switch off.
1
2
3
4
5
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GS450h_U (OM30D01U)
6556-3. Do-it-yourself maintenance
6
Maintenance and care
◆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 your Lexus dealer.
■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 loca-
tion of a cut or other damage
If you are not sure, consul t 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 properly. After driving for about 20 min-
utes, the tire pressure warning light blinks for 1 minute and stays on to indicate a sys-
tem malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has sel-
dom 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 pressure
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 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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GS450h_U (OM30D01U)
6-3. Do-it-yourself maintenance
■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.
■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, which-
ever is greater.
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are in adequate for driving on snow-covered or
icy roads. For driving on snow-covered road s or icy roads, the use of snow tires is
recommended. When installing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions as well as for use year-round. All season
tires, however, do not have adequate traction performance compared with snow
tires in heavy or loose snow. Also, all seas on tires fall short in acceleration and han-
dling performance compared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires.
If you need snow tires, select tires of th e same size, construction and load capacity
as the originally installed tires. Since your vehicle has radial tires as original equip-
ment, make sure your snow tires also have radial construction. Do not install stud-
ded tires without first checking local regulations for possible restrictions. Snow
tires should be installed on all wheels. ( P. 3 1 9 )
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the load
limit at maximum cold tire inflation pressure
mentioned on the sidewall of the tire.
(
P. 795)