
4447-1. Maintenance and care
IS300h_EE(OM53D56E)
CAUTION
■When washing the vehicle
Do not apply water to the inside of the engine compartment. Doing so may cause the
electrical components etc. to catch fire.
■When cleaning the windshield (vehicles with rain-sensing windshield wipers)
●When the upper part of the windshield where the raindrop sensor is located is
touched by hand
●When a wet rag or similar is held close to the raindrop sensor
●If something bumps against the windshield
●If you directly touch the raindrop sensor bo dy or if something bumps into the raindrop
sensor
■Precautions regarding the exhaust pipes
Exhaust gases cause the exhaust pipes to become quite hot.
When washing the vehicle, be careful not to touch the pipes until they have cooled suf-
ficiently, as touching hot exhaust pipes can cause burns.
■Precaution regarding the rear bumper with Blind Spot Monitor (if equipped)
If the paint of the rear bumper is chipped or scratched, the system may malfunction. If
this occurs, consult any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Set the wipers to the intermittent windshield
wipers. ( →P. 2 4 1 )
If AUTO mode is selected, the wipers may
operate unexpectedly in the following situa-
tions, and may result in hands being caught or
other serious injuries and cause damage to the
wiper blades.

4507-2. Maintenance
IS300h_EE(OM53D56E)
■Where to go for maintenance service?
In order to maintain your vehicle in the best possible condition, Lexus recommends that
maintenance service operations as well as other inspections and repairs be carried out
by authorized Lexus dealers or repairers or other duly qualified and equipped profes-
sionals. For repairs and services covered by your warranty, please visit an authorized
Lexus dealer or repairer, who will use genuine Lexus parts in repairing any difficulties you
may encounter. There can also be advantag es in utilizing authorized Lexus dealers or
repairers for non-warranty repairs and services, as members of the Lexus network will be
able to expertly assist you with any difficulties you may encounter.
Your Lexus dealer or repairer, or another duly qualified and equipped professional will
perform all of the scheduled maintenance on your vehicle reliably and economically due
to their experience with Lexus vehicles.
■Does your vehicle need repairs?
Be on the alert for changes in performance and sounds, and visual tip-offs that indicate
service is needed. Some important clues are:
●Engine missing, stumbling or pinging
●Appreciable loss of power
●Strange engine noises
●A fluid leak under the vehicle (However, water dripping from the air conditioning sys-
tem after use is normal.)
●Change in exhaust sound (This may indicate a dangerous carbon monoxide leak. Drive
with the windows open and have the exhaust system checked immediately.)
●Flat-looking tires, excessive tire squeal when cornering, uneven tire wear
●Vehicle pulls to one side when driven straight on a level road
●Strange noises related to suspension movement
●Loss of brake effectiveness, spongy feeling brake pedal, pedal almost touches the floor,
vehicle pulls to one side when braking
●Engine coolant temperature continually higher than normal ( →P. 1 0 9 )
If you notice any of these clues, take your vehicle to any authorized Lexus dealer or
repairer, or another duly qualified and equipp ed professional as soon as possible. Your
vehicle may need adjustment or repair.
CAUTION
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and possible
death or serious injury.
■Handling of the 12-volt battery
12-volt battery posts, terminals and related accessories contain lead and lead com-
pounds which are known to cause brain damage. Wash your hands after handling.
( → P. 4 6 3 )

4597-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
CAUTION
■Used engine oil
●Used engine oil contains potentially harmful contaminants which may cause skin dis-
orders such as inflammation and skin cancer, so care should be taken to avoid pro-
longed and repeated contact. To remove used engine oil from your skin, wash
thoroughly with soap and water.
●Dispose of used oil and filters only in a safe and acceptable manner. Do not dispose of
used oil and filters in household trash, in sewers or onto the ground.
Call any authorized Lexus dealer or repairer, or another duly qualified and equipped
professional, service station or auto parts store for information concerning recycling
or disposal.
●Do not leave used engine oil within the reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■When replacing the engine oil
●Be careful not to spill engine oil on the vehicle components.
●Avoid overfilling, or the engine could be damaged.
●Check the oil level on the dipstick every time you refill the vehicle.
●Be sure the engine oil filler cap is properly tightened.

4617-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid
organic acid technology.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized water.
(Minimum temperature: -35 °C [-31 °F])
For more details about coolant, contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
■If the coolant level drops within a short time of replenishing
Visually check the radiators, hoses, engine/power control unit coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional, test the cap and check for leaks in the cooling sys-
tem.
CAUTION
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or water filler cap.
( → P. 5 74 )
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of water and
antifreeze must be used to provide proper lubrication, corrosion protection and cool-
ing. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.

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.

5208-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
●Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal.
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the hybrid system
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional as soon as possible.
Visible s ymp toms
Audible symptoms
Operational symptoms

5218-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
Brake system warning light (warning buzzer)*1
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
→ Immediately stop the vehicle in a safe place and contact any
authorized Lexus dealer or repairer, or another duly qualified
and equipped professional. Continuing to drive the vehicle may
be dangerous.
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system
→ Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
immediately.
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
→ Immediately stop the vehicle in a safe place and contact any
authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The emission control system (if equipped);
• The electronic engine control system; or
• The electronic throttle control system
→ Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
immediately.

5318-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Indicates that the hybrid battery (traction battery) is lowA buzzer also sounds.
→ When stopping the vehicle for a long period of time,
shift the shift lever to P. The hybrid battery (traction
battery) cannot be charged with the shift lever in N.
Indicates a malfunction in the EPS (Electric Power Steer-
ing) system
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 vehicle is being driven at 5 km/h (3
mph) or more with the parking brake still engaged
A buzzer also sounds.
→ Release the parking brake.
Indicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system
A buzzer also sounds.
→ Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates a malfunction in:
•The ABS; or
• The brake assist system
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 engine coolant temperature is too high
A buzzer also sounds.
→ P. 5 7 1
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)