overheating TOYOTA MIRAI 2022 Owners Manual

15Pictorial index
Owners Manual_USA_M62084_en
Precautions for winter seas on.............................................. P.320
To prevent freezing (windshield wiper de-icer)
*............ P.329, 338
Precautions for car wash (vehicles with rain-sensing windshield wip-
ers) ....................................................................................... P.382
Fuel door ...................................................... ....................... P.203
Refueling method ............................................... .................. P.203
Fuel type/hydrogen t anks’ fuel capacity ........................ ....... P.483
Tires.......................................................... ........................... P.403
Tire size/inflation pressure ................................... ........ P.403, 487
Winter tires/tire chains ....................................... .................. P.320
Checking/rotation/tire pressur e warning system ..................P.403
Coping with flat tires......................................... .................... P.455
Hood ........................................................... ......................... P.393
Opening ............................................................................... P.393
Fuel cell unit compartment cover ............................... .......... P.396
Coping with overheating ...................................................... P.476
Warning messages ............................................... ............... P.451
Headlights/daytime running lights
*.................................. P.191
Parking lights/dayt ime running lights
*............................. P.191
Turn signal lights ............................................. .................. P.182
Tail lights.................................................... ......................... P.191
Tail lights.................................................... ......................... P.191
Stop lights
License plate lights........................................... ................. P.191
Back-up lights
Changing the shift position to R ............................... ............ P.177
Side marker lights ............................................. ................. P.191
Light bulbs of the exterior lights for driving
(Replacing method: P.429)

1735-2. Driving procedures
Owners Manual_USA_M62084_en
5
Driving
Shutdown Due to Freezing Stop in
a Safe Place See Owner’s Man-
ual” may be displayed in the multi-
information display.
The fuel cell system is frozen and
cannot be started. Contact your Toy-
ota dealer.
●The power output will be tempo-
rarily limited until the fuel cell sys-
tem reaches full operating
temperature.
●When the traction battery is
extremely cold (below approxi-
mately -22˚F [-3 0˚C]) under the
influence of outsi de temperature,
it may not be poss ible to start the
fuel cell system. In this case, try to
start the fuel ce ll system again
after the temperat ure of the trac-
tion battery increases due to the
outside temperature increase etc.
■If the fuel cell system does not
start
●The immobilizer system may not
have been deactivated. ( P. 6 9 )
Contact your Toyota dealer.
●If a message related to start-up is
shown on the multi-information
display, read the message and fol-
low the instructions.
●Check that the fuel door is closed.
When the fuel doo r is open, the
fuel cell system cannot be started.
Close the fuel door before starting
the system. ( P.205)
■Sounds and vibrations specific
to a fuel cell vehicle
 P. 7 5
■If the 12-volt battery is dis-
charged
The fuel cell system cannot be
started using the smart key system.
Refer to P.471to res tart the fuel cell
system.
■Electronic key battery depletion
 P. 1 1 8
■Conditions affecting operation
 P.132
■Notes for the entry function
 P.132
■If “Smart Key System Malfunc-
tion See Owner’s Manual” is
displayed on the multi-informa-
tion display
The system may be malfunctioning.
Have the vehicle inspected by your
Toyota dealer immediately.
■Steering lock function
●After turning the power switch off
and opening and closing the
doors, the steeri ng wheel will be
locked due to the steering lock
function. Operating the power
switch again automatically can-
cels the steering lock.
●When the steering lock cannot be
released, “Push Power Switch
while Turning Steering Wheel in
Either Direction” will be displayed
on the multi-information display.
Press the power switch shortly
and firmly while turning the steer-
ing wheel left and right.
●To prevent the steering lock motor
from overheating , the motor may
be suspended if the fuel cell sys-
tem is turned on and off repeat-
edly in a short period of time. In
this case, refrain from operating
the power switch. After about 10
seconds, the steering lock motor
will resume functioning.
■If the “READY” indicator does
not come on
In the event that the “READY” indi-
cator does not come on even after

1855-2. Driving procedures
Owners Manual_USA_M62084_en
5
Driving
■Parking brake automatic
release function
●When the shift position is shifted
from P, the parking brake will be
released in automatic mode.
●When all of the following condi-
tions are met in manual mode, the
parking brake can be released by
depressing the accelerator pedal.
• The driver’s door is closed
• The driver is wearing the seat belt
• The shift position is in D or R
■If “Parking Brake Temporarily
Unavailable” i s displayed on
the multi-information display
If the parking brake is operated
repeatedly over a short period of
time, the system may restrict opera-
tion to prevent overheating. If this
happens, refrain from operating the
parking brake. Nor mal operation will
return after about 1 minute.
■If “Parking Brake Unavailable”
is displayed on the multi-infor-
mation display
Operate the parking brake switch. If
the message does not disappear
after operating the switch several
times, the system may be malfunc-
tioning. Have the vehicle inspected
by your Toyota dealer.
■Parking brake operation sound
When the parking brake operates, a
motor sound (whirring sound) may
be heard. This does not indicate a
malfunction.
■Parking brake operation
●Depending on the power switch
mode, the parking brake indicator
light will turn on and stay on as
described below:
ON: Comes on until the parking
brake is released.
Not in ON: Stays on for approxi-
mately 15 seconds.
●When the power switch is turned
off with the parking brake set, the
parking brake indicator light will
stay on for about 15 seconds. This 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.161
■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.447
■Usage in winter time
 P.320
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 o r 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.

1865-2. Driving procedures
Owners Manual_USA_M62084_en
Turns the brake hold system on
The brake hold standby indicator
(green) comes on. While the
system is holding the brake, the
brake hold operated indicator (yel-
low) comes on.
■Brake hold system operating
conditions
The brake hold system cannot be
turned on in the following condi-
tions:
●The driver’s door is not closed.
●The driver is not wearing the seat
NOTICE
■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.
Brake Hold
The brake hold system
keeps the brake applied
when the shift position is in
D or N with the system on
and the brake pedal has
been depressed to stop the
vehicle. The system
releases the brake when the
accelerator pedal is
depressed with the shift
position in D to allow
smooth start off.
Enabling the system

3185-5. Using the driving support systems
Owners Manual_USA_M62084_en
■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.

3456-1. Using the air conditioning system and defogger
Owners Manual_USA_M62084_en
6
Interior features
7 Settings are complete with any of
the following.
• Operate the button and turn OFF the rear control panel.
• Press the power switch.
• Do not operate the power switch for approximately 10 seconds.
■Customization
Some functions can be customized.
(  P.508)
FunctionSettingsIndicator
Reaction
Time
Fast
A little fast
Normal
A little
slow
Slow
Operation
sounds
ON
OFF
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.

4768-2. Steps to take in an emergency
Owners Manual_USA_M62084_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.442) 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.442) comes on
 Steam comes out from under the hood.
Parts name for cooling components

Owners Manual_USA_M62084_en
Alphabetical Index529
Roof film ............................... 381
Seat belts ............................. 384
Clock ......................................... 97
Coat hooks .............................. 362
Condenser .............................. 398
Console box ............................ 351
Consumption screen.............. 111
Coolant .................................... 397 Capacity ............................... 484
Checking .............................. 397
Preparing and c hecking before
winter.................................. 320
Cooling system ...................... 397 Fuel cell system overheating 477
Overheating.......................... 477
Cruise control Dynamic radar cruise control with full-speed range .......... 237
Cup holders ............................ 350
Current fuel economy ............ 101
Curtain shield airbags ............. 34
Customizable features ........... 498
D
Daytime running light system191
Defogger Outside rear view mirrors ... 327, 334
Rear window ................ 327, 334
Windshield.................... 326, 334
Digital Rearview Mirror .......... 144
Dimension ............................... 482
Dinghy towing ........................ 171
Display Dynamic radar cruise control with full-speed range .......... 237
Head-up display ................... 107
Intuitive parking assist .......... 254
LTA (Lane Tracing Assist) ..... 229
Multi-information display ...... 100
Parking Support Brake function (rear pedestrians) ............... 282 RCD (Rear Camera Detection)
...........................................269
Rear Camera Detection (RCD) ...........................................269
Toyota multi-operation touch 353
Toyota Teammate Advanced Park ....................................287
Warning message.................451
Display change button .............98
Do-it-yourself maintenance ...387
Door courtesy lights...............346
Door lock Doors ....................................121
Smart key system .................130
Wireless remote control........ 119
Doors .......................................121 Automatic door locking and unlocking system ................125
Door glasses ........................156
Door lock ..............................121
Open door warning buzzer .122, 124
Outside rear view mirrors .....154
Rear door child-protectors ....124
Drive distance .........................104
Drive information ....................104
Driver’s seat position memory ...............................................136Driving position memory .......136
Memory recall function .........138
Power easy access system ..136
Driving .....................................161 Break-in tips .........................162
Correct driving posture ...........27
Driving mode select switch ...313
Fuel cell vehicle driving tips ....89
Procedures ...........................161
Winter drive tips....................320
Driving informatio n display ...101
Driving position memory .......136 Memory recall function .........138
Power easy access system ..136

Owners Manual_USA_M62084_en
Alphabetical Index531
Front seats .............................. 135Adjustment ........................... 135
Cleaning ............................... 384
Correct driving posture ........... 27
Driving position memory....... 136
Head restraints ..................... 139
Memory recall function ......... 138
Power easy access system .. 136
Seat heaters ......................... 342
Seat position memory .......... 136
Seat ventilators .................... 342
Front side marker light Light switch .......................... 191
Replacing light bulbs ............ 429
Front turn signal lights .......... 182 Replacing light bulbs ............ 429
Turn signal lever ................... 182
Fuel .......................................... 203 Capacity ............................... 483
Fuel gauge ............................. 97
Refueling .............................. 203
Type ..................................... 483
Warning light ........................ 447
Fuel cell stack ..................... 74, 79 Fuel cell stack cover............. 396
Fuel cell stack coolant ........... 397 Checking .............................. 397
Preparing and c hecking before
winter.................................. 320
Fuel cell stack cover .............. 396
Fuel cell system ....................... 74 Acoustic vehicle alerting system............................................. 76
Emergency shut off system .... 87
High voltage components....... 79
If the fuel cell system will not
start .................................... 466
Overheating.......................... 477
Power switch ........................ 172
Precautions ............................ 79
Predictive efficient drive ......... 77
Starting the fuel cell system . 172 Water release .......................189
Fuel cell system indicator....102, 111
Fuel cell unit Compartment........................395
Fuel cell unit compartment cover...........................................396
Fuel cell unit compartment cover ...............................................396
Fuel cell vehicle ........................74 Charging the traction battery ..76
Driving tips..............................89
Handling hydrogen gas ..........84
Hydrogen gas .........................83
Hydrogen-related components79
Maintenance, repair, recycling, and disposal .........................75
Power output restriction ..........82
Power switch ........................172
Regenerative braking .............76
Road accident cautions ..........86
Running out of fuel .................81
Service plugs ..........................85
Sounds and vibrations ............75
Starting the system ...............172
Traction battery air intake vents .............................................88
Fuel cell vehicle driving tips....89
Fuel consumption Average fuel economy ..........101
Current fuel economy ...........101
Fuel door .................................203 Refueling ..............................203
When the fuel door cannot be opened ...............................468
Fuel economy .........................101
Fuel gauge.................................97
Fuses .......................................425
G
Garage door opene r ...............371
Gauges ......................................97

534Alphabetical Index
Owners Manual_USA_M62084_en
Vanity mirrors ....................... 369
Multi-information display....... 100 Air purification screen........... 111
Audio system-linked display . 104
Changing the display............ 100
Consumption screen ............ 111
Driving information display ... 101
Driving support system informa-tion display ......................... 104
Dynamic radar cruise control with full-speed range .......... 237
ECO Accelerator Guidance .. 102
Eco score ............................. 102
Energy monitor ..................... 111
Fuel cell system indicator ..... 102
Fuel economy....................... 101
LTA (Lane Tracing Assist) ..... 229
Menu icons ........................... 101
Meter control switches ......... 100
Navigation system-linked display ........................................... 104
Settings ................................ 105
Suggestion function.............. 106
Tire inflation pressure ........... 105
Tire pressure ........................ 405
Vehicle information display... 104
Warning message ................ 451
N
Navigation system-linked display ....................................... 104, 107
O
Odometer .................................. 98
Odometer and trip meter display Display change button............ 98
Display items .......................... 98
Opener Fuel door .............................. 203
Hood..................................... 393
Trunk .................................... 127 Outer foot lights......................346
Outside rear view mirrors
Adjustment ...........................154
BSM (Blind Spot M onitor) .....249
Folding..................................155
Mirror position me mory.........136
Outside rear view mirror defog- gers ............................327, 334
RCTA (Rear Cross Traffic Alert) ...........................................263
Outside temperature ................97
Overheating.............................476
P
Panic mode ............................. 119
Parking assist .........................284
Parking assist sens ors (intuitive
parking assist) ......................254
Parking brake ..........................183 Brake system warning light ..441
Operation..............................183
Parking brake engaged warning buzzer.................................185
Warning light.........................447
Warning message.................185
Parking lights Light switch...........................191
Replacing light bulbs ............429
Parking Support Brake (PKSB) ...............................................273Enabling/disabling the system ...........................................274
Parking Support Brake function (rear pedestrians) ...............282
Parking Support Brake function (rear-crossing vehicles) ......280
Parking Support Brake function (static objects) ....................278
Warning lights .......................445
Warning message.................277
PCS (Pre-Collision System) ...212 Enabling/disabling the system