Page 411 of 628

4116-1. Using the air conditioning system and defogger
Owners Manual_USA_M42C01_en
6
Interior features
■Electronic key battery depletion
P. 1 6 2
■When the electronic key bat-
tery is fully depleted
P. 4 9 7
■Customization
Setting (e.g. Operation using “A/C”
on the wireless remote control) can
be changed. (Customizable fea-
tures: P.575)*: If equipped
WARNING
■Precautions for the Remote
Air Conditioning System
●Do not use the system if people
are in the vehicle.
Even when the system is in use,
the internal temperature may
still reach a high or low level
due to features such as the
automatic shut-off. Children and
pets left inside the vehicle may
suffer heatstroke dehydration or
hypothermia, or could result in
death or serious injury.
●Depending on the surrounding
environment, signals from the
wireless switch may transmit
further than expected. Pay
appropriate attention to the
vehicle’s surroundings and use
the switch only when necessary.
●Do not operate “A/C” if the hood
is open. The air conditioning
may operate unintentionally and
objects may be drawn into the
electrical cooling fan.
NOTICE
■To prevent the traction bat-
tery from being discharged
through incorrect operation
Use “A/C” only when necessary.
Heated steering
wheel*/seat heat-
ers*/seat ventila-
tors*/radiant heater*
Heated steering wheel
Warms up the grip of the
steering wheel
Seat heaters
Warm up the seat upholstery
Seat ventilators
Maintain good airflow on the
seat upholstery by sucking air
into the seats
Radiant heaters
Warm up the feet of the front
seats
WARNING
■To prevent minor burn inju-
ries
Care should be taken if anyone in
the following categories comes in
contact with the steering wheel or
seats when the heater is on:
●Babies, small children, the
elderly, the sick and the physi-
cally challenged
●Persons with sensitive skin
●Persons who are fatigued
●Persons who have taken alco-
hol or drugs that induce sleep
(sleeping drugs, cold remedies,
etc.)
Page 460 of 628

4607-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
7-3.Do-it-yourself maintenance
Do-it-yourself ser vice
precautions
If you perform maintenance
by yourself, be sure to fol-
low the correct procedure
as given in these sections.
Maintenance
ItemsParts and tools
12-volt bat-
tery condi-
tion (P.468)
•Warm water
• Baking soda
•Grease
• Conventional
wrench (for termi-
nal clamp bolts)
Brake fluid
level
( P.468)
• FMVSS No.116
DOT 3 or SAE
J1703 brake fluid
FMVSS No.116
DOT 4 or SAE
J1704 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake
fluid)
Power control
unit coolant
level
( P.467)
• In order to ensure
maximum perfor-
mance of the trac-
tion battery
cooling system
and limit risks of
battery short-cir-
cuit and other
damage to your
vehicle, Toyota
recommends
using “Toyota
Genuine Traction
Battery Coolant”
or similar high-
quality ethylene
glycol-based, low
electric conductiv-
ity coolant, non-
amine and non-
borate coolant
with azole addi-
tives.
• Funnel (used only for adding coolant)
ItemsParts and tools
Page 462 of 628
4627-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
1Pull the hood lock release
lever.
The hood will pop up slightly.
2Push the auxiliary catch lever
to the left and lift the hood.
WARNING
■When working near the elec-
tric cooling fan or radiator
grille
Be sure the power switch is OFF.
With the power switch in ON, the
electric cooling fan may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. ( P.466)
■Safety glasses
Wear safety glasses to prevent
flying or falling material, fluid
spray, etc., from getting in your
eyes.
Hood
Opening the hood
Page 465 of 628
4657-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
7
Maintenance and care
Heater coolant reservoir ( P.465)
Washer fluid tank ( P.471)
Power control unit coolant reservoir ( P.467)
12-volt battery ( P.468)
Brake fluid reservoir ( P.468)
Fuse box ( P.499)
Radiator ( P.466)
Condenser ( P.466)
Electric cooling fan
The coolant level is satisfactory
if it is between the “MAX” and “MIN” lines on the reservoir
when the EV system is cold.
Motor compar tment
Components
Checking the heater cool-
ant
Page 466 of 628

4667-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the “MIN”
line, add coolant up to the “MAX”
line. (P.545)
■Coolant selection
Only use “Toyota Super Long Life
Coolant” or a similar high quality
ethylene glycol based non-silicate,
non-amine, non-nitrite, and nonbo-
rate coolant with long-life hybrid
organic acid technology.
“Toyota Super Long Life Coolant” is
a mixture of 50% coolant and 50%
deionized water. (Minimum tem-
perature: -31°F [-35°C])
For more details about coolant, con-
tact your Toyota dealer.
■If the coolant level drops within
a short time of replenishing
Visually check the radiator, hoses,
power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have your
Toyota dealer, test the cap and
check for leaks in the cooling sys-
tem.
Check the radiator and con-
denser and clear away any for-
eign objects.
If either of the above parts is
extremely dirty or you are not
sure of their condition, have
your vehicle inspected Toyota
dealer.
WARNING
■When the heater system is
hot
Do not remove the heater coolant
reservoir caps.
The heater system may be under
pressure and may spray hot cool-
ant 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 cooling. 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.
Checking the radiator and
condenser
WARNING
■When the EV system is hot
Do not touch the radiator or con-
denser as they may be hot and
cause serious injuries, such as
burns.
Page 467 of 628

4677-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
7
Maintenance and care
The coolant level is satisfactory
if it is between the “MAX” and
“MIN” lines on the reservoir
when the EV system is cold. Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the “MIN”
line, add coolant up to the “MAX”
line.
■Coolant selection
In order to ensure maximum perfor-
mance of the traction battery cooling
system and limit risks of battery
short-circuit and other damage to your vehicle, Toyota recommends
using “Toyota Genuine Traction Bat-
tery Coolant” or similar high-quality
ethylene glycol-based, low electric
conductivity coolant, non-amine and
non-borate coolant with azole addi-
tives.
Toyota cannot guarantee that the
use of a product o
ther than “Toyota
Genuine Traction Battery Coolant”
will prevent risks of battery short-cir-
cuit or other damage.
Never use water as it will cause
damage.
Do not reuse cool ant that has been
removed from the radiator.
For more details about coolant, con-
tact your Toyota dealer.
■If the coolant level drops within
a short time of replenishing
Visually check the hoses, heater
coolant reservoir caps, drain cock
and water pump.
If you cannot find a leak, have your
Toyota dealer, t est the cap and
check for leaks in the cooling sys-
tem.
WARNING
■When the electric cooling fan
are operating
Do not touch the motor compart-
ment.
With the power switch in ON, the
electric cooling fan may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. Be sure the
power switch is OFF when work-
ing near the electric cooling fan or
radiator grille.
Checking the power con-
trol unit coolant
WARNING
■When the EV system is hot
Do not remove the power control
unit coolant reservoir caps.
The cooling system may be under
pressure and may spray hot cool-
ant if the cap is removed, causing
serious injuries, such as burns.
Page 468 of 628

4687-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
Reservoir cap
“MAX” line
“MIN” line
■Adding fluid
Make sure to check the fluid
type and prepare the necessary
item.
Fluid type
FMVSS No.116 DOT 3 or SAE J1703 brake fluid
FMVSS No.116 DOT 4 or SAE
J1704 brake fluid
Item
Clean funnel
■Brake fluid can absorb moisture
from the air
Excess moisture in the brake fluid
can cause a dangerous loss of brak-
ing efficiency. Use only newly
opened brake fluid.
Check the 12-volt battery as fol-
lows.
■12-volt battery exterior
Make sure that the 12-volt bat-
tery terminals are not corroded
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 cooling. 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 d amaging parts or
paint.
Checking and adding the
brake fluidWARNING
■When filling the reservoir
Take care as brake fluid can harm
your hands and 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,
see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level
to go down slight ly as the brake
pads wear out or when the fluid
level in the accumulator is high.
If the reservoir needs frequent
refilling, there m ay be a serious
problem.
Checking the 12-volt bat-
tery
Page 545 of 628

5458-2. Steps to take in an emergency
Owners Manual_USA_M42C01_en
8
When trouble arises1 Stop the vehicle in a safe
place and turn off the air con-
ditioning system.
2 Leave the EV system operat-
ing and carefully lift the hood.
3 Check if the cooling fan is
operating.
If the fan is operating:
Wait until the “EV System
overheated Output power
reduced” message disap-
WARNING
■When replacing the 12-volt
battery
●When the vent plug is close to
the hold down cl amp, the bat-
tery fluid (acid) may leak.
●For information regarding bat-
tery replacement, contact your
Toyota dealer.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan.
If your vehicle over-
heats
When “EV System over-
heated Output power
reduced” is shown on the
multi-information display,
your vehicle may be over-
heating.
NOTICE
■Cooling system coolant
The radiator coolant is exclusive
for radiator usage. Damage may
occur when water or any other
type of coolant is used, so never
use any other fluid. When there is
no “Toyota Genuine Traction Bat-
tery Coolant”, immediately contact
your Toyota dealer.
Correction procedures