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Maintenance and care
12-volt battery
The 12-volt battery is located on the
right-hand side of trunk.
Remove the 12-volt battery cover.
Install the cover
Lift the tab to secure to the trunk
liner
Location
Removing the 12-volt battery cover
Installing the 12-volt battery cover
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2
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Make sure that the 12-volt battery terminals are not corroded and that there are
no loose connections, cracks, or loose cl
amps. Make sure that the terminal cov-
ers are secured over the battery terminals.
Terminals
Hold-down clamp
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the charge r is off when connecting and disconnecting
the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow th e procedure below to initialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
●Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the 12-volt battery. If this happens, use the
wireless remote control or the mechan ical key to lock/unlock the doors.
●Start the hybrid system with the power sw itch in ACCESSORY mode. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.
●The power switch mode is recorded by the v ehicle. If the 12-volt battery is reconnected,
the vehicle will return the power switch mode to the status it was in before the 12-volt bat-
tery was disconnected. Make sure to turn o ff the power switch before disconnect the 12-
volt battery. Take extra care when connecting the 12-volt battery if the power switch mode
prior to discharge is unknown.
If the system will not start even after multip le attempts at all methods above, contact your
Lexus dealer.
Exterior
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2
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2
3
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Maintenance and care
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may produce
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 battery in
a garage or closed room where th ere is insufficient ventilation.
■How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if charged
at a quicker rate.
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate 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 fe el pain or burning, get medical attention
immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your s kin. Immediately take off the clothing and fol-
low the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergenc y medical attention immedi-
ately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause gas (hydro-
gen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact your Lexus dealer.
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ES300h_OM_OM33D45U_(U)7-3. Do-it-yourself maintenance
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.
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Maintenance and care
Tires
Check if the treadwear indicators are showing on the tires. Also check the tires
for uneven wear, such as excessive wear on one side of the tread.
Check the spare tire condition and pressure if not rotated.
New tread
Worn tread
Treadwear indicator
The location of treadwear indicato rs is shown by a “TWI” or “Δ” mark, etc., molded
into the sidewall of each tire.
Replace the tires if the treadwear indicators are showing on a tire.
Rotate the tires in the order shown.
To equalize tire wear and extend tire life,
Lexus recommends that tire rotation is
carried out at the same interval as tire
inspection.
Do not fail to initialize the tire pressure
warning system after tire rotation.
Replace or rotate tires in accordance with maintenance schedules and tread-
wear.
Checking tires
Tire rotation
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2
3
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Your vehicle is equipped with a tire pressure warning system that uses tire pres-
sure warning valves and transmitters to
detect low tire inflation pressure before
serious problems arise.
●If the tire pressure drops below a predet ermined level, the driver is warned by
a screen display and a warning light. ( →P. 505)
●The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( →P. 91)
The illustration used is intended as an
example, and may differ from the image
that is actually disp layed on the multi-
information display.
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pr essure warning valves and transmitters
must also be installed.
When new tire pressure wa rning 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 initia lized. Have tire pressure warning valve
and transmitter ID codes registered by your Lexus dealer. ( →P. 463)
◆Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the following circum-
stances:
●When rotating the tires.
●When the tire inflation pressure is changed such as when changing travel-
ing 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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Maintenance and care
■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 th e specified cold tire inflation pressure
level. ( →P. 545)
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.
Press and hold the tire pressure
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.
◆Registering ID codes
The tire pressure warning valve and tran smitter is equipped with a unique ID
code. When replacing a tire pressure warning valve and transmitter, it is nec-
essary to register the ID code. Have the ID code registered by your Lexus
dealer.
1
2
3
4
5
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ES300h_OM_OM33D45U_(U)7-3. Do-it-yourself maintenance
■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.
■When rotating the tires
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.
■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 Ce rtification 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. 550)