Page 450 of 628

4367-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
CAUTION
The engine compartment contains many mechanisms and fluids that may move
suddenly, become hot, or become electrically energized. To avoid death or seri-
ous injury, observe the following precautions.
When working on the engine compartment
Make sure that the “ACCESSORY” or “IGNITION ON” on the multi-infor-
mation 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 mani-
fold, 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
flammable.
Take care because brake fluid can harm your hands or eyes and damage
painted surfaces. 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 electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature is
high. (P. 446)
Safety glasses
Wear safety glasses to prevent flying or falling 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.
Page 453 of 628
4397-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
12-volt battery
P. 447
Engine compartment
Power control unit coolant res-
ervoir (P. 444)
Engine oil level dipstick
(P. 440)
Engine coolant reservoir
(P. 444)
Engine oil filler cap
(P. 441)Fuse box (P. 475)
Washer fluid tank (P. 446)
Electric cooling fans
Condenser (P. 446)
Power control unit coolant
radiator (P. 446)
Engine coolant radiator
(P. 446)1
2
3
4
5
6
7
8
9
10
Page 454 of 628
4407-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
With the engine at operating temperature and turned off, check the oil
level on the dipstick.
Checking the engine oil
Park the vehicle on level ground. After warming up the engine and
turning off the hybrid system, wait more than 5 minutes for the oil to
drain back into the bottom of the engine.
Holding a rag under the end,
pull the dipstick out.
Wipe the dipstick clean.
Reinsert the dipstick fully.
Holding a rag under the end,
pull the dipstick out and check
the oil level.
Low
Normal
Excessive
The shape of the dipstick may
differ depending on the type of
vehicle or engine.
Wipe the dipstick and reinsert it fully.
Engine oil
1
2
3
4
5
1
2
3
6
Page 455 of 628
4417-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Adding engine oil
If the oil level is below or near
the low level mark, add engine
oil of the same type as that
already in the engine.
Make sure to check the oil type and prepare the items needed before
adding oil.
Remove the oil filler cap by turning it counterclockwise.
Add engine oil slowly, checking the dipstick.
Install the oil filler cap by turning it clockwise.
Engine oil selectionP. 5 6 5
Oil quantity (Low Full) 1.5 L (1.6 qt., 1.3 Imp. qt.)
Items Clean funnel
1
2
3
Page 456 of 628

4427-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
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 (if equipped)
The engine oil maintenance data should be reset. Perform the following proce-
dures:
While the hybrid system is operating, switch the multi-information display to
the “Settings” screen. (P. 118)
Select “Maintenance System” on the “Settings” screen.
Select “Yes” on the “Maintenance System” screen.
A message will be displayed when the
reset procedure has been completed.
1
2
3
Page 457 of 628

4437-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
CAUTION
Used engine oil
Used engine oil contains potentially harmful contaminants which may cause
skin disorders such as inflammation and skin cancer, so care should be taken
to avoid prolonged 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 con-
cerning 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.
Page 508 of 628

4947-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
CAUTION
Replacing light bulbs
Turn off the lights. Do not attempt to replace the bulb immediately after turn-
ing off the lights.
The bulbs become very hot and may cause burns.
Do not touch the glass portion of the light bulb with bare hands. When it is
unavoidable to hold the glass portion, use and hold with a clean dry cloth to
avoid getting moisture and oils on the bulb.
Also, if the bulb is scratched or dropped, it may blow out or crack.
Fully install light bulbs and any parts used to secure them. Failure to do so
may result in heat damage, fire, or water entering the headlight unit. This may
damage the headlights or cause condensation to build up on the lens.
Discharge headlights (if equipped)
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional before replacing the discharge headlights (including
light bulbs).
Do not touch the discharge headlight’s high voltage socket when the head-
lights are turned on.
An extremely high voltage of 30000 V will be discharged and could result in
death or serious injury by electric shock.
Do not attempt to take apart or repair the headlight bulbs, connectors, power
supply circuits, or related components.
Doing so could result in electric shock and death or serious injury.
To prevent damage or fire
Make sure bulbs are fully seated and locked.
Check the wattage of the bulb before installing to prevent heat damage.
Vehicles with discharge headlights: While
the headlights are turned on, and for a
short time after they have been turned off,
metal components at the rear of the head-
light assembly will be extremely hot. To
prevent burns, do not touch these metal
components until you are certain they
have cooled down.
Metal components
Page 534 of 628

5208-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
(If equipped)
Indicates a malfunction in the PCS (Pre-Crash
Safety system)
A buzzer also sounds.
Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly quali-
fied and equipped professional.
(If equipped)
Indicates a malfunction in the BSM (Blind Spot
Monitor) system
A buzzer also sounds.
Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly quali-
fied and equipped professional.
Indicates abnormal engine oil pressure
A buzzer also sounds.
Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer,
or another duly qualified and equipped profes-
sional.
Indicates a malfunction in:
• The regenerative brake system; or
• The electronically controlled brake system
A buzzer also sounds.
Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer,
or another duly qualified and equipped profes-
sional.
Indicates that the Pop Up Hood system has operated
A buzzer also sounds.
Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly quali-
fied and equipped professional.
Indicates a malfunction in the Pop Up Hood system
A buzzer also sounds.
Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly quali-
fied and equipped professional.
Indicates that the hybrid system was stopped while
driving
A buzzer also sounds.
Operate the steering wheel with more force than
usual.
Warning messageDetails/Actions
(Flashes)