2023 TOYOTA MIRAI overheating

15Pictorial index
Owners Manual_USA_M62064_en
Windshield wipers.............................................. ................ P.204
Precautions for winter seas on.............................................. P.327
To prevent freezing (windshield wiper de-icer)
*............ P.337, 347
Precautions for car wash (vehicles with rain-sensing windshield wip-
ers) ....................................................................................... P.394
Fuel door ...................................................... ....................... P.210
Refueling method ............................................... .................. P.210
Fuel type/hydrogen t anks’ fuel capacity ........................ ....... P.497
Tires.......................................................... ........................... P.416
Tire size/inflation pressure ................................... ........ P.416, 501
Winter tires/tire chains ....................................... .................. P.327
Checking/rotation/tire pressur e warning system ..................P.416
Coping with flat tires......................................... .................... P.467
Hood ........................................................... ......................... P.406
Opening ............................................................................... P.406
Fuel cell unit compartment cover ............................... .......... P.409
Coping with overheating ...................................................... P.490
Warning messages ............................................... ............... P.464
Headlights/daytime running lights
*.................................. P.198
Parking lights/dayt ime running lights
*............................. P.198
Turn signal lights ............................................. .................. P.190
Tail lights.................................................... ......................... P.198
Tail lights.................................................... ......................... P.198
Stop lights
License plate lights........................................... ................. P.198
Back-up lights
Changing the shift position to R ............................... ............ P.185
Light bulbs of the exterior lights for driving
(Replacing method: P.443)

1935-2. Driving procedures
Owners Manual_USA_M62064_en
5
Driving
does not indicate a malfunction.
■When the parking brake switch
malfunctions
Automatic mode (automatic brake
setting and releas ing) will be turned
on automatically.
■Parking the vehicle
 P. 1 6 9
■Parking brake engaged warning
buzzer
A buzzer will sound if the vehicle is
driven with the parking brake
engaged. “Parking Brake ON” is dis-
played on the multi-information dis-
play. (with the vehicle reached a
speed of 3 mph [5 km/h])
■If the parking brake indicator
flashes
 P. 4 5 9
■Usage in winter time
 P. 3 2 7
WARNING
■When parking the vehicle
Do not leave a child in the vehicle
alone. The parking brake may be
released unintentionally and there
is the danger of the vehicle mov-
ing that may lead to an accident
resulting in death or serious injury.
NOTICE
■When parking the vehicle
Before you leave the vehicle, set
the parking brake, shift the shift
position to P and make sure that
the vehicle does not move.
■When the system malfunc-
tions
Stop the vehicle in a safe place
and check the warning messages.
■When the parking brake can-
not be released due to a mal-
function
Driving the vehicle with the park-
ing brake set will lead to brake
components overheating, which
may affect braking performance
and increase brake wear.
Have the vehicle inspected by
your Toyota dealer immediately if
this occurs.

3255-5. Using the driving support systems
Owners Manual_USA_M62064_en
5
Driving
■Operating conditions of Active
Cornering Assist
The system operates when the fol-
lowing occurs.
●TRAC/VSC can operate
●The driver is at tempting to accel-
erate while turning
●The system detects that the vehi-
cle is drifting to the outer side
●The brake pedal is released
■Reduced effectiveness of the
EPS system
The effectiveness of the EPS sys-
tem is reduced to prevent the sys-
tem from overheating when there is
frequent steering input over an
extended period of time. The steer-
ing wheel may feel heavy as a
result. Should this occur, refrain
from excessive steering input or
stop the vehicle and turn the fuel
cell system off. The EPS system
should return to normal within 10
minutes.
■Secondary Collision Brake
operating conditions
The system operates when the SRS
airbag sensor detects a collision
while the vehicle is in motion. How-
ever, the system does not operate in
any of the following situations.
●When driving at a low speed
●Components are damaged
■Secondary Collision Brake
automatic cancelation
The system is automatically can-
celed in any of th e following situa-
tions.
●The vehicle speed has decreased
to a certain speed
●A certain amount o f time elapses
during operation
●The accelerator pedal is
depressed a large amount
WARNING
■The ABS does not operate
effectively when
●The limits of tire gripping perfor-
mance have been exceeded
(such as excessively worn tires
on a snow covered road).
●The vehicle hydroplanes while
driving at high speed on wet or
slick roads.
■Stopping distance when the
ABS is operating may exceed
that of normal conditions
The ABS is not designed to
shorten the vehicle’s stopping dis-
tance. Always maintain a safe dis-
tance from the veh icle in front of
you, especially in the following sit-
uations:
●When driving on dirt, gravel or
snow-covered roads
●When driving with tire chains
●When driving over bumps in the
road
●When driving over roads with
potholes or uneven surfaces
■TRAC/VSC may not operate
effectively when
Directional control and power may
not be achievable while driving on
slippery road surfaces, even if the
TRAC/VSC system is operating.
Drive the vehicle carefully in con-
ditions where stability and power
may be lost.
■Active Cornering Assist does
not operate effectively when
●Do not overly rely on Active
Cornering Assist. Active Corner-
ing Assist may not operate
effectively when accelerating
down slopes or driving on slip-
pery road surfaces.

3546-1. Using the air conditioning system and defogger
Owners Manual_USA_M62064_en
WARNING
■To prevent overheating and
minor burn injuries
Observe the following precautions
when using the seat heaters.
●Do not cover the seat with a
blanket or cushion when using
the seat heater.
●Do not use seat heater more
than necessary.

4908-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
Label
Fuel cell stack coolant reservoir
Inverter coolant reservoir
If your vehicle overheats
The following may indicate that your vehicle is overheating.
The high coolant temperature warning light ( P.455) comes on
or flashes, or a loss of fuel cell system power is experienced.
(For example, the vehicle speed does not increase.)
 The fuel cell system overheat warning light ( P.455) comes on
 Steam comes out from under the hood.
Parts name for cooling components

Owners Manual_USA_M62064_en
Alphabetical Index545
Riding with children ................ 51
Seat belt extender precautions............................................. 30
Seat belt precautions ....... 29, 51
Trunk precautions................. 132
Child-protectors ..................... 130
Cleaning .......................... 392, 396 Aluminum wheel ornaments . 392
Aluminum wheels ................. 392
Exterior ................................. 392
Interior .................................. 396
Radar sensor........................ 215
Roof film ............................... 393
Seat belts ............................. 396
Clock ................................. 99, 102
Coat hooks .............................. 372
Condenser .............................. 411
Console box ............................ 360
Consumption screen.............. 119
Coolant .................................... 410 Capacity ............................... 498
Checking .............................. 410
Preparing and c hecking before
winter.................................. 327
Cooling system ...................... 410 Fuel cell system overheating 491
Overheating.......................... 491
Cruise control Dynamic radar cruise control with full-speed range .......... 244
Cup holders ............................ 359
Current fuel economy ............ 107
Curtain shield airbags ............. 34
Customizable features ........... 512
D
Daytime running light system198
Defogger Outside rear view mirrors ... 335, 342
Rear window ................ 335, 342
Windshield.................... 334, 342 Digital Rear-view Mirror .........150
Dimension ...............................496
Dinghy towing .........................179
Display
Dynamic radar cruise control with full-speed range ..........244
Head-up display ................... 114
Intuitive parking assist ..........262
LTA (Lane Tracing Assist) .....236
Multi-information display.......105
Parking Support Brake function (pedestrians rear of the vehicle)...........................................292
RCD (Rear Camera Detection) ...........................................278
Rear Camera Detection (RCD) ...........................................278
Warning message.................464
Display change button ...100, 104
Do-it-yourself maintenance ...400
Door courtesy lights...............355
Door lock Doors ....................................127
Smart key system .................136
Wireless remote control........125
Doors .......................................127 Automatic door locking and unlocking system ................131
Door glasses ........................162
Door lock ..............................127
Open door warning buzzer .128, 130
Outside rear view mirrors .....160
Rear door child-protectors ....130
Drive distance ......................... 111
Drive information .................... 111
Driver’s seat position memory ...............................................142Driving position memory .......142
Memory recall function .........144
Power easy access system ..142

Owners Manual_USA_M62064_en
Alphabetical Index547
F
Flat tire .................................... 467Tire pressure warning system........................................... 418
Floor mats ................................. 26
Fluid Brake .................................... 500
Transmission ........................ 500
Washer ................................. 412
Footwell light .................... ...... 355
Front footwell lights ............... 355
Front passenger occupant clas- sification system .................... 46
Front seats .............................. 141 Adjustment ........................... 141
Cleaning ............................... 396
Correct driving posture ........... 27
Driving position memory....... 142
Head restraints ..................... 145
Memory recall function ......... 144
Power easy access system .. 142
Seat heaters ......................... 351
Seat position memory .......... 142
Seat ventilators .................... 351
Front side marker light Light switch .......................... 198
Replacing light bulbs ............ 443
Front turn signal lights .......... 190 Replacing light bulbs ............ 443
Turn signal lever ................... 190
Fuel .......................................... 210 Capacity ............................... 497
Fuel gauge ..................... 99, 102
Refueling .............................. 210
Type ..................................... 497
Warning light ........................ 460
Fuel Cell Electric Vehicle ......... 76 Charging the traction battery .. 78
Driving tips ............................. 91
Handling hydrogen gas .......... 86
Hydrogen gas ......................... 85 Hydrogen-related components81
Maintenance, repair, recycling,
and disposal .........................78
Power output restriction ..........84
Power switch ........................180
Regenerative braking .............78
Road accident cautions ..........88
Running out of fuel .................83
Service plugs ..........................87
Sounds and vibrations ............77
Starting the system ...............180
Traction battery air intake vents .............................................90
Fuel cell electric vehicle driving tips ...........................................91
Fuel cell stack .....................76, 81 Fuel cell stack cover .............409
Fuel cell stack coolant ...........410 Checking ..............................410
Preparing and checking before winter ..................................327
Fuel cell stack cover ..............409
Fuel cell system ........................76 Acoustic vehicle alerting system.............................................79
Emergency shut off system ....89
High voltage components .......81
If the fuel cell system will not start ....................................480
Overheating ..........................491
Power switch ........................180
Precautions ............................81
Predictive efficient drive..........79
Starting the fuel cell system .180
Water release .......................196
Fuel cell System Indicator ...103, 108, 118
Fuel cell unit Compartment........................408
Fuel cell unit compartment cover...........................................409

550Alphabetical Index
Owners Manual_USA_M62064_en
M
Maintenance Do-it-yourself maintenance .. 404
General maintenance ........... 401
Maintenance data................. 496
Maintenance requirements... 400
Menu icons ............................. 107
Meter Clock .............................. 99, 102
Driving range .................. 99, 102
Indicators................................ 97
Instrument panel light control................................... 100, 104
Meter control switches ......... 106
Meters ............................ 99, 102
Multi-information display ...... 105
Settings ................................ 111
Warning lights................. 95, 454
Warning message ................ 464
Meter control switches .......... 106
Mirrors Digital Rear-view Mirror........ 150
Inside rear view mirror.......... 149
Outside rear view mirror defog-gers ............................ 335, 342
Outside rear view mirrors ..... 160
Vanity mirrors ....................... 380
Multi-information display....... 105 Air purification screen........... 119
Audio system-linked display . 111
Changing the display............ 106
Consumption screen ............ 119
Driving information display ... 107
Driving support system informa-tion display ......................... 110
Dynamic radar cruise control with full-speed range .......... 244
ECO Accelerator Guidance .. 108
Eco score ............................. 108
Energy monitor ..................... 119
Fuel cell System Indicator .... 108 Fuel economy .......................107
LTA (Lane Tracing Assist) .....236
Menu icons ...........................107
Meter control switches..........106
Navigation system-linked display
........................................... 110
Settings ................................ 111
Suggestion function .............. 112
Tire inflation pressure ........... 111
Tire pressure ...... ..................418
Vehicle information display ... 111
Warning message.................464
N
Navigation system-linked display ....................................... 110, 114
O
Odometer.........................100, 104
Odometer and trip meter display Display change button ..100, 104
Display items ................100, 104
Opener Fuel door ..............................210
Hood .....................................406
Trunk ....................................133
Outer foot lights......................355
Outside rear view mirrors Adjustment ...........................160
BSM (Blind Spot M onitor) .....256
Folding..................................161
Mirror position me mory.........142
Outside rear view mirror defog- gers ............................335, 342
RCTA (Rear Cross Traffic Alert) ...........................................272
Outside temperature ........99, 102
Overheating.............................490