2021 TOYOTA HIGHLANDER HYBRID cooling

4807-2. Steps to take in an emergency
HIGHLANDER HV_Uare shown on the multi-informa-
tion display, it may indicate a mal-
function. Immediat
ely stop the
vehicle and contact your Toyota
dealer.
• “Braking Power Low Stop in a
Safe Place See Owner's Manual”
• “Oil Pressure Low Stop in a Safe Place See Owner's Manual”
• “Charging System Malfunction Stop in a Safe Place See Owner's
Manual”
• “Stop in a Safe Place See Owner's Manual”
• “Shift to P See Owner's Manual”
●If any of the following messages
are shown on the multi-informa-
tion display, the vehicle may have
run out of fuel. Stop the vehicle in
a safe place and, if the fuel level is
low, refuel the vehicle.
• “Hybrid System Stopped”
• “Engine Stopped”
●If any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal-
function. Have the vehicle
inspected by you r Toyota dealer
immediately.
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunc- tion”
• “Accelerator System Malfunction”
• “Smart Key System Malfunction
See Owner's Manual”
●If any of the following messages
are shown on the multi-informa-
tion display, follow the instruc-
tions.
• “Engine Coolant Temp High Stop in a Safe Place See Owner's Man-
ual” ( P.504)
• “Maintenance Required for Trac- tion Battery Cooling Parts See
Owner's Manual” ( P.441)
NOTICE
■If “High Power Consumption
Partial Limit on AC/Heater
Operation” is displayed fre-
quently
There is a possible malfunction
relating to the charging system or
the 12-volt battery may be deteri-
orating. Have the vehicle
inspected by you r Toyota dealer.

5037-2. Steps to take in an emergency
7
When trouble arises
HIGHLANDER HV_U
WARNING
●In the event that battery fluid
comes into contact with the skin
or eyes, immediately wash the
affected area with water and
seek medical attention. Place a
wet sponge or cloth over the
affected area until medical
attention can be received.
●Always wash your hands after
handling the 12-volt battery sup-
port, terminals, and other bat-
tery-related parts.
●Do not allow child ren near the
12-volt battery.
■After recharging the 12-volt
battery
Have the 12-volt battery
inspected at your Toyota dealer
as soon as possible.
If the 12-volt battery is deteriorat-
ing, continued use may cause the
12-volt battery to emit a malodor-
ous gas, which may be detrimen-
tal to the health of passengers.
■When replacing the 12-volt
battery
●When the vent plug and indica-
tor are close to the hold down
clamp, the battery fluid (sulfuric
acid) may leak.
●For information regarding
12-volt battery replacement,
contact your Toyota dealer.
●After replacing, securely attach
the exhaust hose and exhaust
hole plug to the exhaust hole of
the replaced 12-volt battery. If
not properly installed, gases
(hydrogen) may leak into the
vehicle interior, and there is the
possible danger of the gas ignit-
ing and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan or belt.
■To prevent damaging the
vehicle
The exclusive jump starting termi-
nal is to be used when charging
the 12-volt battery from another
vehicle in an emergency. It cannot
be used to jump start another
vehicle.

5047-2. Steps to take in an emergency
HIGHLANDER HV_U
If the engine coolant tempera-
ture gauge enters the red
zone or “Engine Coolant
Temp High Stop in a Safe
Place See Owner’s Manual”
is shown on the multi-informa-
tion display
1 Stop the vehicle in a safe
place and turn off the air con-
ditioning system, and then
stop the hybrid system.
2 If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the hybrid system has
cooled down sufficiently,
inspect the hoses and radia-
tor core (radiator) for any
leaks.
Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
4The coolant level is satisfac-
tory if it is between the
“FULL” and “LOW” lines on
the reservoir.
Reservoir
“FULL” line
“LOW” line
If your vehicle over-
heats
The following may indicate
that your vehicle is over-
heating.
The needle of the engine
coolant temperature gauge
( P.89) enters the red zone
or a loss of hybrid system
power 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 Output
Power Reduced” is shown
on the multi-information dis-
play.
 Steam comes out from
under the hood.
Correction procedures

5057-2. Steps to take in an emergency
7
When trouble arises
HIGHLANDER HV_U
Radiator cap
5 Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
6Start the hybrid system and
turn the air conditioning sys-
tem on to check that the radi-
ator cooling fan operates and
to check for coolant leaks
from the radiator or hoses.
The fan operates when the air con-
ditioning system is turned on imme-
diately after a cold start. Confirm
that the fan is op erating by check-
ing the fan sound and air flow. If it is
difficult to check th ese, turn the air
conditioning system on and off
repeatedly. (The fan may not oper-
ate in freezing temperatures.)
7 If the fan is not operating:
Stop the hybrid system
immediately and contact your
Toyota dealer.
If the fan is operating:
Have the vehicle inspected at
the nearest Toyota dealer.
8 Check if “Engine Coolant
Temp High Stop in a Safe
Place See Owner's Manual”
is shown on the multi-infor-
mation display.
If the message does not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is not displayed:
Have the vehicle inspected at the
nearest Toyota dealer.
If “Hybrid System Over-
heated Output Power
Reduced” is shown on the
multi-information display
1 Stop the vehicle in a safe
place.
2 Stop the hybrid system and
carefully lift the hood.
3 After the hybrid system has
cooled down, inspect the
hoses and radiator core (radi-
ator) for any leaks.
Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
4The coolant level is satisfac-
tory if it is between the

5077-2. Steps to take in an emergency
7
When trouble arises
HIGHLANDER HV_U
1Stop the hybrid system. Shift
the shift lever to P and set the
parking brake.
2 Remove the mud, snow or
sand from around the front
wheels.
3 Place wood, stones or some
other material under the front
wheels to help provide trac-
tion.
4 Restart the hybrid system.
5 Shift the shift lever to D or R
and release the parking
brake. Then, while exercising
caution, depress the acceler-
ator pedal.
■When it is difficult to free the
vehicle
Press to turn off TRAC.
NOTICE
■To prevent damage to the
cooling system
Observe the following precau-
tions:
●Avoid contaminating the coolant
with foreign matter (such as
sand or dust, etc.).
●Do not use any coolant additive.
If the vehicle becomes
stuck
Carry out the following pro-
cedures if the tires spin or
the vehicle becomes stuck
in mud, dirt or snow:
Recovering procedure

5138-1. Specifications
8
Vehicle specifications
HIGHLANDER HV_U
Outside temperature
SAE 0W-16 is the best choice
for good fuel economy and good
starting in cold weather.
If SAE 0W-16 is not available,
SAE 0W-20 oil may be used.
However, it must be replaced
with SAE 0W-16 at the next oil
change.
Oil viscosity (0W-16 is explained
here as an example):
• The 0W in 0W-16 indicates the characteristic of the oil
which allows cold startability.
Oils with a lower value before the W allow for easier starting
of the engine in cold weather.
• The 16 in 0W-16 indicates the viscosity characteristic of the
oil when the oil is at high tem-
perature. An oil with a higher
viscosity (one with a higher
value) may be better suited if
the vehicle is operated at high
speeds, or under extreme
load conditions.
How to read oil container label:
API registered mark is added to
some oil containers to help you
select the oil you should use.
Cooling system
Capacity
Gasoline
engine10.5 qt. (9.9 L , 8.7 Imp. qt.)
Power con-
trol unit2.0 qt. (1.9 L, 1.7 Imp. qt.)
Coolant type
Use either of the following:
 “Toyota Super Long Life Coolant”
 Similar high-quality et hylene glycol-based
non-silicate, non -amine, non-nitrite, and
non-borate coolant with long-life hybrid organic
acid technology
Do not use pla in water alone.

560Alphabetical Index
HIGHLANDER HV_UBack-up lights
Replacing light bulbs ............ 449
Battery (12-volt battery) Battery checking................... 421
If the 12-volt battery is dis-charged .............................. 498
Preparing and c hecking before
winter.................................. 333
Replacing ............................. 501
Warning light ........................ 467
Battery (traction battery) ......... 75
Blind Spot Monitor (BSM) ...... 286
Brake Brake hold ............................ 227
Fluid ............................. 420, 515
Parking brake ....................... 224
Regenerative braking ............. 72
Warning light ........................ 466
Brake assist ............................ 325
Break-in tips ........ ................... 191
Brightness control Instrument panel light control . 92
BSM (Blind Spot Monitor) ...... 286
Buzzer Hands off steering wheel warn-ing (LTA) ............................. 269
C
Care Exterior ................................. 400
Interior .................................. 403
Seat belts ............................. 403
Wheels and wheel ornaments........................................... 400
Cargo capacity ....................... 200
Cargo net hooks .. ................... 370
Chains ..................................... 334
Child restraint system Fixed with a LATCH system ... 60
Fixed with a seat belt ............. 55
Front passenger occupant clas-sification system ................... 43 Points to remember ................50
Riding with children ................49
Types of child restraint system
installation method ...............52
Using an anchor bracket ........62
Child safety 12-volt battery precautions .422, 502
Airbag precautions .................39
Back door precautions..........135
Child restraint system .............52
Heated steering wheel and seat heater precautio ns..............358
How your child should wear the seat belt ................................28
Moon roof precautions..........183
Panoramic moon roof precau- tions ....................................187
Power window lock switch ....181
Power window precautions...180
Rear door child-protectors ....134
Seat belt extender precautions .............................................29
Seat belt precautions..............49
Child-protectors......................134
Cleaning Exterior .................................400
Interior ..................................403
Radar sensor ........................244
Seat belts .............................403
Wheels and wheel ornaments...........................................400
Clock ....................................89, 92
Coat hooks ..............................383
Condenser ............. ..................419
Console box ............................366
Conversation mirror ...............389
Cooling system .......................418 Engine overheating ..............504
Hybrid system overheating ...505