Page 472 of 692
4726-2. Using the air conditioning system
IS300h_EE(OM53D89E)
■Option control screen
Select on the air conditioning co ntrol screen to display the option
control screen. The functions can be switched on and off.
■Side display operation screen (Vehicles with a 10.3-inch display)
With a Lexus Display Audio With a 10.3-inch display
Removing pollen from the ai r (Pollen removal mode) (P. 474)1
With “DUAL” modeWithout “DUAL” mode
Select the air flow mode
Adjust the left-hand side temperature setting
Adjust the fan speed setting
Adjust the right-hand side temperature setting
Select to set auto mode on/off
Select to set cooling and de humidification function on/off
Adjust the temperature fo r driver and passenger seats separately (“DUAL”
mode) ( P. 473)
Adjust the temperature setting
1
2
3
4
5
6
7
8
Page 477 of 692

4776-2. Using the air conditioning system
6
Interior features
IS300h_EE(OM53D89E)
■Registering air conditioning settings to electronic keys (vehicles with driving position
memory)
●Unlocking the vehicle using an electronic key and turning the power switch to ON mode will recall that ke y’s registered air conditioning settings.
●When the power switch is turned off, the current air conditioning settings will automati-
cally be registered to the electronic key that was used to unlock the vehicle.
●The system may not operate correctly if more than one electronic key is in the vicinity or
if the smart entry & start system is used to unlock a passenger door.
●The doors that can recall the air conditioning setting when unlocked using the smart entry & start system can be changed.* For details, contact any authorized Lexus
retailer or Lexus authorized re pairer, or any reliable repairer.
*: The doors that can recall the driving position memory are changed at the same time.
■Using automatic mode
Fan speed is adjusted automatically accordin g to the temperature setting and the ambi-
ent conditions.
Therefore, the fan may stop for a while until wa rm or cool air is ready to flow immediately
after is pressed or “AUTO” is selected.
■Fogging up of the windows
The windows will easily fog up when the hu midity in the vehicle is high. Turning
(“A/C”) on will dehumidify the air from the outlets and defog the windshield effectively.
●If you turn (“A/C”) off, the windows may fog up more easily.
●The windows may fog up if the recirculated air mode is used.
■Outside/recirculated air mode
●When driving on dusty roads such as tunnels or in heavy traffic, set the outside/recircu-
lated air mode button to the recirculated ai r mode. This is effective in preventing out- side air from entering the vehicle interi or. During cooling operation, setting the
recirculated air mode will also cool the vehicle interior effectively.
●Outside/recirculated air mode may automa tically switch depending on the tempera-
ture setting or the inside temperature.
■Operation of the air conditioni ng system in Eco drive mode
In Eco drive mode, the air conditioning system is controlled as follows to prioritize fuel
efficiency:
●Engine speed and compressor operation controlled to restrict heating/cooling capac-
ity
●Fan speed restricted when automatic mode is selected
To improve air conditioning performanc e, perform the following operations:
●Adjust the fan speed
●Turn off Eco drive mode
Page 512 of 692

5127-3. Do-it-yourself maintenance
IS300h_EE(OM53D89E)
WARNING
The engine compartment contains many mechanisms and fluids that may move suddenly, become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the “ACCESSORY” or “I GNITION 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 yo ur 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 disc omfort, 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. 521)
■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 f ilter 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 freq uent refilling, it may indicate a serious problem.
Page 515 of 692
5157-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D89E)
■12-volt battery
P. 522
Engine compartment
Power control unit coolant reser-
voir ( P. 519)
Engine oil level dipstick
( P. 516)
Engine coolant reservoir
( P. 519)
Engine oil filler cap
( P. 517)
Fuse box ( P. 552)
Washer fluid tank ( P. 521)
Electric cooling fans
Condenser ( P. 521)
Power control unit coolant
radiator ( P. 521)
Engine coolant radiator
( P. 521)
1
2
3
4
5
6
7
8
9
10
Page 520 of 692

5207-3. Do-it-yourself maintenance
IS300h_EE(OM53D89E)
■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 mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -35 C [-31F])
For more details about coolant, contact any authorized Lexus retailer or Lexus autho-
rized repairer, or an y reliable repairer.
■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 retailer or Lexus authorized repairer, or any reliable repairer, test the cap an d check for leaks in the cooling system.
WARNING
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or water filler cap. ( P. 636)
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.
Page 600 of 692

6008-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
Carrying out the corresponding action turns the messages off.
(If equipped)
Indicates that the PCS (Pre-Collision System) is tempo- rarily unavailable
When conditions improve, the system resumes
operation. If this message is displayed continuously, have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repairer, or any reliable
repairer.
(If equipped)
Indicates that part of th e PCS (Pre-Collision System)
sensor is dirty, covered with ice, etc.
Remove any dirt, ice, etc.
Other displayed messages
Warning messageDetails/Actions
(Flashes)
(Flashes)
Warning messageDetails/Actions
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 retailer or Lexus authorized repairer, or
any reliable repairer.
Page 635 of 692
6358-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure th at they do not become entangled in the
cooling fans or belt.
■Exclusive jump starting terminal
The exclusive jump starting terminal is inte nded to charge the 12-volt battery on your
vehicle from another vehicle in an emergency. Do not use the exclusive jump starting
terminal to jump start another vehicle.
Page 636 of 692

6368-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
●The needle of the engine coolant temperature gauge (P. 105) enters the
red zone or a loss of hybrid system po wer is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Ou tput Power” is shown on the multi-
information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red zone
Stop the vehicle in a safe place and tu rn off the air conditioning system, and
then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core (radi-
ator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact any autho-
rized Lexus retailer or Lexus authorized repairer, or any reli-
able repairer.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2