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4647-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
The meanings of each caution symbol on the top of the 12-volt battery are as fol-
lows:
■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 charger 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 the 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 entry & start system may not be possible immedi-
ately after reconnecting the 12-volt battery. If this happens, use the wireless remote
control or the mechanical key to lock/unlock the doors.
●Start the hybrid system with the power switch 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 vehicle. 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
battery was disconnected. Make sure to turn off the power switch before disconnecting
the 12-volt battery. Take extra care when connecting the 12-volt battery if the power
switch mode prior to the 12-volt battery being disconnected is unknown.
If the system will not start even after multip le attempts at all the methods above, contact
any authorized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional.
Caution symbols
No smoking, no naked
flames, no sparks12-volt battery acid
Shield eyesNote operatin g instructions
Keep away from childrenExplosive gas
1
2
3
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4657-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
CAUTION
■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 there is insufficient ventilation.
■How to recharge the 12-volt battery
Only perform a slow charge (4 A — 5 A). Th e 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 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 fol-
low the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk . Get emergency 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 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.
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4777-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
Remove the 12-volt battery cover. (→P. 463)
Take out the jack. For tightening
For loosening
If the jack is too tightly installed to be
removed by hand, insert a tool, such
as the screwdriver included with the
vehicle, into the hole of the jack (por-
tion “A”) and loosen the jack.
CAUTION
■Using the tire jack
Observe the following precautions.
Improper use of the tire jack may cause the vehicle to suddenly fall off the jack, leading
to death or serious injury.
●Do not use the tire jack for any purpose other than replacing tires or installing and
removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a tire.
Do not use it on other vehicles, and do not use other tire jacks for replacing tires on
this vehicle.
●Put the jack properly in its jack point.
●Do not put any part of your body under the vehicle while it is supported by the jack.
●Do not start the hybrid system or drive the vehicle while the vehicle is supported by
the jack.
●Do not raise the vehicle while someone is inside.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greater than that required to replace the tire.
●Use a jack stand if it is necessary to get under the vehicle.
●When lowering the vehicle, make sure that there is no-one near the vehicle. If there
are people nearby, warn them vocally before lowering.
Taking out the jack
1
2
1
2
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4887-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
●Flathead screwdriver
●Small flathead screwdriver
●Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, wrap the
tip of the screwdriver with tape.
Remove the battery cover.
To prevent damage to the key, wrap the
tip of the screwdriver with tape.
Electronic key battery
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3
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4897-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
Remove the depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
■Use a CR2032 lithium battery
●Batteries can be purchased at any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional, local electrical appliance shops or camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to local laws.
■When the card key battery needs to be replaced (if equipped)
The battery for the card key is available only at Lexus dealers. Your Lexus dealer can
replace the battery for you.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart entry & start system and wireless remote control will not function properly.
●The operational range will be reduced.
■Certification for the key battery
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to the local laws.
4
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4907-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
CAUTION
■Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking. Keep away
from children. Failure to do so could result in death or serious injury.
■Lithium battery precautions
CAUTION:
RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT TYPE.
DISPOSE OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other component inside the remote control.
●Do not bend either of the battery terminals.
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511
8When trouble arises
IS300h_EE(OM53D56E)
8-1. Essential informationEmergency flashers.................... 512
If your vehicle has to be stopped in an
emergency .................................. 513 8-2. Steps to take in an
emergency
If your vehicle needs to be towed .......................................514
If you think something is wrong ........................................... 520
If a warning light turns on or a warning buzzer
sounds............................................521
If a warning message is displayed......................................527
If you have a flat tire (vehicles with
emergency tire puncture
repair kit) .................................... 545
If you have a flat tire (vehicles with run-flat
tires).............................................. 559
If the hybrid system will not start ...............................560
If the shift lever cannot be shifted from P ..................... 562
If the electronic key does not operate properly ............. 563
If the 12-volt battery is discharged ................................. 566
If your vehicle overheats ...........571
If the vehicle becomes stuck ......................... 575
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512
IS300h_EE(OM53D56E)8-1. Essential information
Press the switch.
All the turn signals will flash.
To turn them off, press the switch once
again.
■Emergency flashers
If the emergency flashers are used for a long time while the hybrid system is not operat-
ing (while the “READY” indicator is not illu
minated), the 12-volt battery may discharge.
Emergency flashers
The emergency flashers are used to warn other drivers when the vehicle has
to be stopped in the road due to a breakdown, etc.