4527-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
CAUTION
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energized. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the “ACCESSORY” or “IGNITION ON” on the multi-information
display and the “READY” indicator are both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, power control unit, radiator, exhaust manifold, etc.
right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble.
●Take care because brake fluid can harm your hands or eyes and damage painted sur-
faces. If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, consult a doctor.
■When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the elec tric cooling fans may automatically start to
run if the air conditioning is on and/or the coolant temperature is high. ( →P. 4 6 2 )
■Safety glasses
Wear safety glasses to prevent flying or fallin g material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to dirt
in the air.
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear or when
the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, it may indicate a serious problem.
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
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4747-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drivetrain 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 an emergency tire puncture repair kit: Do not tow anything if a tire that
has been repaired using the emergency tire puncture repair kit is installed. The load
on the tire may cause unexpected damage to the tire.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light may
not come on even if the tire inflation pressu re is low, or it may come on when the tire
inflation pressure is actually normal.
5258-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
■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 due to being in a noisy location or audio
sound.
CAUTION
■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.
XVehicles with an emergency tire puncture repair kit
●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, repair the
flat tire by using emergency tire puncture repair kit.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could lose
control of the steering wheel or the brakes.
XVehicles with run-flat tires
●Decelerate to the lowest appropriate speed as soon as possible. Do not drive over 60
km/h (37 mph).
●Check and adjust the tire in flation 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. Have the tire replaced by the nearest
authorized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional.
●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.
5378-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Indicates that operation of large electricity consuming
systems such as the air conditioning system are sus-
pended
→ Stop using unnecessary electric components to
reduce electricity consumpt ion. Wait a while until
the electric power supply is restored.
(If equipped)
Indicates that the LDA (Lane Departure Alert) system
cannot be used because the vehicle speed is lower than
approximately 50 km/h (32 mph)
→ Drive the vehicle at 50 km/h (32 mph) or higher.
Indicates that the EV drive mode is not available*
The reason the EV drive mode is not available (the
vehicle is idling, hybrid battery [traction battery]
charge is low, speed is higher than the EV drive mode
operating speed range, accelerator pedal is
depressed too much) may be displayed.
A buzzer also sounds.
→ Use the EV drive mode when it becomes available.
Wa r n i n g m e s s a g eDetails/Actions
5398-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
■Warning messages
The warning message illustrations used are intended as examples, and may differ from
the image that is actually displayed on the multi-information display.
■Warning message in radar cruise mode (if equipped)
In the following situations, the warning messag e may not be displayed even if vehicle-to-
vehicle distance decreases:
●When the speed of the preceding vehicle matches or exceeds your vehicle speed
●When the preceding vehicle is traveling at an extremely slow speed
●Immediately after the cruise control speed was set
●When depressing the accelerator pedal
■The LDA (Lane Departure Alert) lane departure warning function (if equipped)
In the following situations, the warning messag e will not be displayed even if a lane line is
crossed.
●When the vehicle speed deviates from the operating range of the LDA system func-
tions
●When the lane lines cannot be recognized
■Resetting the message indicating maintenance is required
Make sure to reset the oil change system. ( →P. 4 5 8 )
■Warning buzzer
→P. 5 2 5
5418-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Once3 times
The electronic key was carried out-
side the vehicle and a door other
than the driver’s door was opened
and closed while the power switch
was in a mode other than off.
→Bring the electronic key back
into the vehicle.
The driver’s door was opened and
closed while the electronic key was
not in the vehicle, the shift lever was
in P and the power switch was not
turned off.
→Tu r n t h e p o w e r s w i t c h o f f .
→ Bring the electronic key back
into the vehicle.
9 times
An attempt was made to drive when
the electronic key was not inside the
vehicle.
→Confirm that the electronic key
is inside the vehicle.
Con-
tinuous
An attempt was made to lock the
doors using the smart entry & start
system while the electronic key was
still inside the vehicle.
→Retrieve the electronic key
from the vehicle and lock the
doors again.
OnceCon-
tinuous
An attempt was made to lock either
front door by opening a door and
putting the inside lock button into
the lock position, then closing the
door by pulling on the outside door
handle with the electronic key still
inside the vehicle.
→Retrieve the electronic key
from the vehicle and lock the
doors again.
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes)
(Vehicles with the entry function)
(Flashes)
5618-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
One of the following may be the cause of the problem:
●One or both of the 12-volt battery terminals may be disconnected.
●The 12-volt battery may be discharged. (→P. 5 6 6 )
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional if the problem cannot be repaired, or if repair procedures are
unknown.
When the hybrid system does not start, the following steps can be used as an
interim measure to start the hybrid system if the power switch is functioning nor-
mally:
Set the parking brake.
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for about 15 seconds while depressing the
brake pedal firmly.
Even if the hybrid system can be started using the above steps, the system may
be malfunctioning. Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
The interior lights and he adlights do not turn on, or the horn does not
sound.
Emergency start function
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