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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.
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4587-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
■Engine oil consumption
A certain amount of engine oil will be consumed while driving. In the following situations,
oil consumption may increase, and engine oil may need to be refilled in between oil
maintenance intervals.
●When the engine is new, for example directly after purchasing the vehicle or after
replacing the engine
●If low quality oil or oil of an inappropriate viscosity is used
●When driving at high engine speeds or with a heavy load, when towing, or when driving
while accelerating or decelerating frequently
●When leaving the engine idling for a long time, or when driving frequently through
heavy traffic
■After changing the engine oil
The engine oil maintenance data should be reset. Perform the following procedures:
While the vehicle is stopped, press the meter control switch on the steering wheel.
Press the < or > meter control switch on the steering wheel, select, and then
press the meter control switch.
Press ∧ or ∨ meter control switch on the steering wheel to select “Oil Maintenance”
and then press .
Select “Yes” and then press .
A message will be displayed on the multi-information display.
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2
3
4
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4627-3. Do-it-yourself maintenance
IS300h_EE(OM53D56E)
Check the radiators and condenser and clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of their condi-
tion, have your vehicle inspected by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
If any washer does not work or the
warning message appears on the multi-
information display, the washer tank
may be empty. Add washer fluid.
Radiators and condenser
CAUTION
■When the hybrid system is hot
Do not touch the radiators or condenser as they may be hot and cause serious injuries,
such as burns.
Washer fluid
CAUTION
■When adding washer fluid
Do not add washer fluid when the hybrid system is hot or operating as washer fluid
contains alcohol and may catch fire if spilled on the engine etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bottle.
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4717-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
■Situations in which the tire pressure warning system may not operate properly
●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 Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. 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 wheelhousings.
• If the tire inflation pressure is extremely higher than the specified level.
• If tires not equipped with tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-
port or other facility that generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless communication device
●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.
■The initialization operation
●Make sure to carry out initialization afte r adjusting the tire inflation pressure.
Also, make sure the tires are cold before carry ing out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the power switch off during initialization, it is not neces-
sary to press the reset switch again as init ialization will restart automatically when the
power switch has been turned to ON mode for the next time.
●If you accidentally press the reset switch wh en initialization is not necessary, adjust the
tire inflation pressure to the specified leve l when the tires are cold, and conduct initial-
ization again.
■Warning performance of the tire pressure warning system
The warning of the tire pressu re warning system will change in accordance with the con-
ditions under which it was initialized. For this reason, the system may give a warning even
if the tire pressure does not reach a low enough level, or if the pressure is higher than the
pressure that was adjusted to when the system was initialized.
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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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514
IS300h_EE(OM53D56E)8-2. Steps to take in an emergency
The following may indicate a problem with your transmission. Contact any
authorized Lexus dealer or repairer, or another duly qualified and equipped pro-
fessional or commercial towing service before towing.
●A warning message for the hybrid system is shown on the multi-information
display and the vehicle does not move.
●The vehicle makes an abnormal sound.
If your vehicle needs to be towed
If towing is necessary, we recommend having your vehicle towed by any
authorized Lexus dealer or repairer,
or another duly qualified and equipped
professional or commercial towing service, using a wheel-lift type truck or
flatbed truck.
Use a safety chain system for all towing, and abide by all state/provincial and
local laws.
Situations when it is necessary to contact dealers before towing
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5278-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Master warning light
The master warning light also comes on or flashes in order to indicate that a message
is currently being displayed on the multi-information display.
Multi-information display
If any of the warning lights come on again after the following actions have been
performed, contact any authorized Lexu s dealer or repairer, or another duly
qualified and equipped professional.
If a warning message is displayed
If a warning is shown on the multi-information display, stay calm and perform
the following actions:
XExcept F SPORT models XF SPORT models (when the main
meter is in the center position)
XF SPORT models (when the main
meter is in the right-side position)
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5358-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Indicates a malfunction in the brake override systemA buzzer also sounds.
→ Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates that engine oil level is low
A buzzer also sounds.
→ Check the level of engine oil, and add if necessary.
Indicates that the hybrid system has overheated
This message may be displayed when driving under
severe operating conditions. (For example, when driv-
ing up a long steep hill.)
A buzzer also sounds.
→ Stop and check. ( →P. 5 7 1 )
Indicates a malfunction in:
• The automatic headlight leveling system; or
• The Automatic High Beam system (if equipped)
• The LED headlight system (if equipped)
A buzzer also sounds.
→ Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates that the accelerator and brake pedal are being
depressed simultaneously
→Release the accelerator or brake pedal.
Maintenance of the hybrid battery (traction battery)
cooling component is required
The filter may be clogged, the air intake vent may be
blocked or there may be a gap in the duct
→ Have maintenance performed on the hybrid battery
(traction battery) cooling component by any autho-
rized Lexus dealer or repairer, or another duly qual-
ified and equipped professional.
Indicates that the washer fluid level is low
→Add washer fluid.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)