2021 TOYOTA HIGHLANDER HYBRID engine overheat

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

5067-2. Steps to take in an emergency
HIGHLANDER HV_U
“FULL” and “LOW” lines on
the reservoir.
Reservoir
“FULL” line
“LOW” line
5 Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
6After stopping the hybrid sys-
tem and waiting for 5 minutes
or more, start the hybrid sys-
tem again and check if
“Hybrid System Overheated
Output Power Reduced” is
shown on the for the
multi-information display.
If the message does not disappear:
Stop the hybrid system and contact
your Toyota dealer.
If the message is not displayed:
The hybrid system temperature has
dropped and the vehicle may be
driven normally. However, if the m
essage appears
again frequently, contact your Toy-
ota dealer.
WARNING
■When inspecting under the
hood of your vehicle
Observe the following precau-
tions.
Failure to do so may result in seri-
ous injury such as burns.
●If steam is seen coming from
under the hood, do not open the
hood until the steam has sub-
sided. The engine compart-
ment may be very hot.
●After the hybrid system has
been turned off , check that the
“READY” indicator is off.
When the hybrid system is oper-
ating, the gasoline engine may
automatically start, or the cool-
ing fan may suddenly operate
even if the gasoline engine
stops. Do not touch or approach
rotating parts such as the fan,
which may lead to fingers or
clothing (especially a tie, a scarf
or a muffler) getting caught,
resulting in serious injury.
●Do not loosen the radiator cap
and the coolant reservoir caps
while the hybrid system and
radiator are hot.
High temperature steam or
coolant could spray out.
NOTICE
■When adding engine/power
control unit coolant
Add coolant slowly after the
hybrid system has cooled down
sufficiently. Adding cool coolant to
a hot hybrid system too quickly
can cause damage to the hybrid
system.

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

562Alphabetical Index
HIGHLANDER HV_UEDR (Event data recorder)......... 7
E-Four ...................................... 326
Elapsed time ..................... 96, 106
Electric motor (traction motor)71
Electric Power Steering (EPS)
............................................... 326Warning light ........................ 469
Electronic key ......................... 128 Battery-saving function......... 147
If the electronic key does not operate properly ................. 496
Replacing the battery ........... 444
Electronic roof sunshade Jam protection function ........ 186
Operation ............................. 185
Electronically Controlled Brake System (ECB) ....................... 325
Emergency flashers ............... 458
Emergency, in case of If a warning buzzer sounds .. 466
If a warning light turns on ..... 466
If a warning message is dis-played................................. 476
If the 12-volt battery is dis- charged .............................. 498
If the electronic key does not operate properly ................. 496
If the fuel filler door cannot be opened ............................... 495
If the hybrid sy stem will not start
........................................... 493
If the vehicle is trapped in rising water .................................. 459
If you have a flat tire ............. 481
If you lose your keys ............ 495
If you think something is wrong ........................................... 464
If your vehicle becomes stuck ........................................... 507
If your vehicle has to be stopped in an emergency................. 458 If your vehicle needs to be towed
...........................................461
If your vehicle ove rheats ......504
Energy monitor ....................... 117
Engine ACCESSORY mode . ............216
Compartment........................416
Engine switch .......................213
Hood .....................................414
How to start the hybrid system ...........................................213
Identification number ............ 511
If the hybrid sys tem will not start
...........................................493
If your vehicle has to be stopped in an emergency .................458
Ignition switch (power switch) ...........................................213
Overheating ..........................504
Power switch ........................213
Tachometer.............................89
Engine coolant Capacity ...............................513
Checking ..............................418
Preparing and checking before winter ..................................333
Engine coolant temperature gauge .......................................89
Engine oil Capacity ...............................512
Checking ..............................416
Preparing and checking before winter ..................................333
Warning light.........................467
Engine switch (power switch)213 If your vehicle has to be stopped in an emergency .................458
EPS (Electric Po wer Steering)
...............................................326 Warning light.........................469
EV drive mode.........................218
EV indicator...............................72

564Alphabetical Index
HIGHLANDER HV_URear automatic air conditioning
system ................................ 354
Seat heaters ......................... 358
High mounted stoplight Replacing light bulbs ............ 449
High-voltage components ....... 75
Hill-start assist control .......... 325
Hood Open .................................... 414
Hooks Cargo net hooks ................... 370
Coat hooks ........................... 383
Retaining hooks (floor mat) .... 24
Horn ......................................... 165
Hybrid battery (tr action battery)
Location.................................. 75
Specification ......................... 512
Warning message .................. 78
Hybrid battery (traction battery) air vents .................................. 77
Hybrid system .......................... 71 Acoustic vehicle alerting system............................................. 73
Emergency shut off system .... 78
Energy monitor/consumption screen ................................ 117
EV drive mode...................... 218
High voltage components....... 75
Hybrid system precautions ..... 75
If the hybrid sy stem will not start
........................................... 493
Overheating.......................... 505
Power (ignition) switch ......... 213
Regenerative braking ............. 72
Starting the hybrid system.... 213
Hybrid System Indicator .. 90, 115
Hybrid transmission .............. 220 S mode ................................. 222
Hybrid vehicle driving tips .... 331
I
I/M test ..................................... 410 Identification
Engine .................................. 511
Vehicle ..................................510
Ignition switch (power switch) ...............................................213Auto power off fun ction .........216
Changing the power switch modes.................................216
If your vehicle has to be stopped in an emergency .................458
Immobilizer system ..................79
Indicators ..................................86
Initialization Items to initialize ...................542
Maintenance .........................407
Power windows ....................179
Tire pressure w arning system
...........................................430
Inside rear view m irror ...166, 167
Instrument panel light control .92
Interior lights...........................362 Front interior light .................362
Rear interior light ..................362
Intuitive parking assist Function................................292
Warning message.................295
J
JackPositioning a floor jack .........415
Vehicle-equipped jack ..........482
Jack handle .............................482
Jam protection function Electronic roof sunshade ......186
Moon roof .............................182
Panoramic moon r oof ...........186
Power back door ..................140
Power windows ....................179

566Alphabetical Index
HIGHLANDER HV_UOutside rear view mirrors ..... 177
Vanity mirrors ....................... 388
Moon roof Door lock linked moon roof oper-ation ................................... 182
Jam protection function ........ 182
Operation ............................. 182
Multi-information display. 92, 101 Audio system-linked display . 96, 106
AWD Control .................. 97, 106
Driving information display ... 93, 102
Driving support system......... 106
Driving support system informa- tion display ................... 96, 105
Dynamic radar cruise control with full-speed range .......... 271
ECO Accelerator Guidance .. 94, 103
Eco score ....................... 94, 103
Energy monitor ....... 97, 106, 117
Fuel economy................. 94, 102
LTA (Lane Tracing Assist) ..... 266
Menu icons ..................... 92, 101
Meter control switches ... 93, 102
Navigation system-linked display ..................................... 96, 105
Pop-up display ............... 92, 101
Settings .......................... 97, 107
Suggestion function...... 101, 110
Tire pressure .......... 97, 106, 426
Vehicle information display... 96, 106
Warning message 101, 110, 476
N
Navigation system-linked display ................................. 96, 105, 115
Noise from under vehicle .......... 5
Normal mode .......................... 322
O
“ODO TRIP” switch ..................91
Odometer...................................91
Odometer and trip meter display Display items ..........................91
“ODO TRIP” switch .................91
Oil Engine oil..............................512
Rear differential oil................514
Opener Back door .............................137
Fuel filler door.......................240
Hood .....................................414
Outer foot lights Replacing light bulbs ............449
Outside rear view mirrors Adjustment ...........................177
BSM (Blind Sport Monitor) ....286
Linked mirror function when reversing.............................177
Mirror position me mory.........159
Outside rear view mirror defog- gers ............................344, 348
RCTA function.......................300
Outside temperature ................89
Overheating.............................504
P
Panic mode .............................130
Panoramic moon roof Jam protection function ........186
Operation..............................185
Parking assist sens ors (intuitive
parking assist) ......................292
Parking brake Operation..............................224
Parking brake engaged warning buzzer.................................226
Warning light.........................473
Warning message.................226

571Alphabetical Index
HIGHLANDER HV_UTraction Control (TRAC) ........ 325
Traction motor (electric motor)71
Trail Mode ............................... 323
Trailer Sway Control .............. 325
Trailer towing .......................... 201
Transmission
Driving mode select switch... 322
Hybrid transmission.............. 220
If the shift lever cannot be shifted from P................................. 221
S mode ................................. 222
Trip meters ................................ 91
Turn signal lights Replacing light bulbs ............ 449
Turn signal lever ................... 223
U
USB charging ports................ 374
V
Vanity lights ............................ 388
Vanity mirrors ......................... 388
VDIM (Vehicle Dynamics Inte-grated Management) ............ 326
Vehicle data recording ............... 6
Vehicle Dynamics Integrated Management (VDIM) ............. 326
Vehicle identifi cation number510
Vehicle information display ... 96, 106
Vehicle Stability Control (VSC) ............................................... 325
Ventilators (seat ventilators) . 358
VSC (Vehicle Stability Control) ............................................... 325
W
Warning buzzers ABS ...................................... 468
Airbags ................................. 468 Approach warning ................278
Brake hold ............................473
Brake Override System ........468
Brake system ........................466
Charging system ..................467
Downshifting .........................222
Drive-Start Control
................468
Electric power steering .........469
Engine ..................................467
Hands off steering wheel warn- ing (LTA) .............................269
High coolant temperature .....466
Hybrid system .......................467
Hybrid system overheat ........467
Intuitive parking assist .296, 299, 471
Low engine oil pressure .......467
LTA (Lane Tracing Assist) ...260, 264, 470
Open door ....................132, 134
PKSB (Parking Support Brake) ...........................................471
Pre-collision braking .............251
RCTA (Rear Cross Traffic Alert) ...........................................471
RCTA function.......................301
Seat belt .......................469, 470
Warning label ............................75
Warning lights .........................466 ABS ......................................468
Brake hold operated indicator...........................................473
Brake Override System ........468
Brake system ........................466
Charging system ..................467
Drive-Start Control ................468
Electric power steering .........469
High coolant temperature .....466
Hybrid system overheat warning light .....................................467
Intuitive parking assist OFF indi- cator ...................................471