2020 TOYOTA MIRAI overheating

1163. Instrument cluster
MIRAI_OM_USA_OM62073U
NOTICE
■To prevent damage to the fuel cell system and its components
This vehicle is equipped with high coolant temperature warning light
(  P. 418), instead of, coolant temperature gauge.
The fuel cell system may be overheating if the high coolant temperature
warning light flashes or comes on. In this case, immediately st op the
vehicle in a safe place, and che ck the fuel cell system after it has cooled
completely.

2005-2. Driving procedures
MIRAI_OM_USA_OM62073U
Parking brake
To set the parking brake, fully
depress the parking brake pedal
with your left foot while depress-
ing the brake pedal with your right
foot.
(Depressing the pedal again
releases the parking brake.)
■Parking the vehicle
P. 172
■ Parking brake engaged warning buzzer
A buzzer will sound if the vehicle is driven with the parking b rake engaged.
“Release Parking Brake” is displayed on the multi-information d isplay.
■ Warning messages and buzzers
Warning messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution. If a warning message is shown on
the multi-information display, read the message and follow the instructions.
■ If the brake system warning light comes on
P. 418
■ Usage in winter time
P. 302
Operating instructions
(U.S.A.) (Canada)
NOTICE
■When parking the vehicle
Before you leave the vehicle, shift the shift position to P, se t the parking
brake and make sure that the vehicle does not move.
■ Before driving
Fully release the parking brake.
Driving the vehicle with the parking brake set will lead to bra ke components
overheating, which may affect braking performance and increase brake
wear.

2985-5. Using the driving support systems
MIRAI_OM_USA_OM62073U■
Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the s ystem from
overheating when there is frequent steering input over an exten ded period of
time. The steering wheel may feel heavy as a result. Should thi s 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.
■ Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
● When the power switch is turned off
● If only the TRAC system is turned off, the TRAC will turn on wh en vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-e nabling will
not occur when vehicle speed increases
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assi st control will
operate:
● The shift position is in a position other than P or N (when sta rting off forward/
backward on an upward incline).
● The vehicle is stopped.
● The accelerator pedal is not depressed.
● The parking brake is not engaged.
■ Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
● Shift the shift position to P or N.
● The accelerator pedal is depressed.
● The parking brake is engaged.
● Approximately 2 seconds elapse after the brake pedal is release d.

4578-2. Steps to take in an emergency
MIRAI_OM_USA_OM62073U
8
When trouble arises
If your vehicle overheats
The following may indicate that your vehicle is overheating.
● The high coolant temperature warning light ( P. 418) comes on
or flashes, or a loss of fuel ce ll system power is experienced. (For
example, the vehicle s peed does not increase.)
● “FC System Overheat Output Power is Limited” ( P. 426) is dis-
played on the multi-in formation display
● Steam comes out from under the hood.
Label
Fuel cell stack coolant
reservoir Inverter coolant reservoir

515Alphabetical index
MIRAI_OM_USA_OM62073U
Child-protectors....................... 135
Cleaning ........................... 352, 356Aluminum wheels.................. 353
Exterior ................................. 352
Interior................................... 356
Seat belts .............................. 357
Clock ......................................... 328
Coat hooks ............................... 329
Condenser ................................ 371
Console box ............................. 321
Coolant Capacity ................................ 469
Checking ............................... 370
Preparing and checking Warning light ...................... 418
Cooling system ........................ 370 Fuel cell system
overheating......................... 457
Cruise control Dynamic radar cruise
control................................. 253
Cup holders.............................. 322
Curtain shield airbags ............... 37
Customizable features ............ 484 Daytime running light
system.................................... 203
Defogger Outside rear view mirrors ..... 309
Rear window ......................... 309
Windshield ............................ 309
Dimensions .............................. 466
Dinghy towing.......................... 185
Display Drive information .................. 118
Dynamic radar cruise control ................................ 253
Energy monitor ..................... 118
LDA (Lane Departure Alert with steering control) .......... 238
Multi-information display ....... 117
Parking Support Brake function
(for static objects) .............. 279
Warning message ................ 426
Do-it-yourself maintenance .... 364
Door courtesy lights Location ................................ 317
Wattage ................................ 471
Door lock Doors .................................... 132
Key ....................................... 449
Smart key system ................. 132
Wireless remote control ........ 132D
*: Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.

518Alphabetical index
MIRAI_OM_USA_OM62073U
Fuel cell stack ............................ 94
Fuel cell stack coolantCapacity ................................ 469
Checking ............................... 370
Fuel cell system
Characteristics ........................ 86
Cold temperatures ................ 189
Coolant type.......................... 469
Indicators .............................. 109
Multi-information display ....... 117
Precautions ............................. 90
Starting the system ............... 186
Stopping the system ............. 187
Warning lights ....................... 107
Fuel cell system indicator....... 120
Fuel cell vehicles Characteristics ........................ 86
Charging the traction
battery .................................. 89
Driving advice ....................... 102
Emergency shut off system .... 92
Emergency start function ...... 448
Emergency stops .................. 409
Fuel ....................................... 468
Handling hydrogen gas ........... 98
High-voltage components ....... 91
Hydrogen gas ......................... 97
Hydrogen-related
components .......................... 90
If the 12-volt battery is
discharged .......................... 452
If the fuel cell system will not start .................................... 447
Maintenance, repair, recycling, and disposal ......... 89 Opening the fuel door ........... 213
Overheating .......................... 457
Power output restriction .......... 96
Power switch ........................ 186
Precautions............................. 90
Regenerative braking ............. 89
Road accident cautions ........ 100
Running out of fuel ................. 93
Service plugs .......................... 99
Sounds and vibrations ............ 88
Starting the system ............... 186
Traction battery air intake
vent ...................................... 93
Vehicle proximity notification
system .......... ..................... ... 92
Warning message................. 426
Water release ....................... 187
Fuel consumption ........... 121, 122
Fuel door .................................. 213 Refueling .............................. 213
Fuses ........................................ 402
Garage door opener ................ 343
Gauges ..................................... 111
Glove box ................................. 321
Grocery bag hooks.................. 325
G

521Alphabetical index
MIRAI_OM_USA_OM62073U
MaintenanceDo-it-yourself maintenance ... 364
General maintenance ........... 361
Maintenance data ................. 466
Maintenance
requirements ...................... 359
Master warning light........ 421, 426
Meter ......................................... 111 Indicators .............................. 109
Instrument panel light control................................. 113
Meters ................................... 111
Multi-information display ....... 117
Warning lights ....................... 107
Warning message ................. 426
Meter light control ................... 113
Mirrors Inside rear view mirror .......... 162
Outside rear view mirror defoggers ........................... 309
Outside rear view mirrors...... 164
Vanity mirrors........................ 327
MP3 disc
*
Multi-information display ........ 117
Drive information................... 118
Dynamic radar cruise control................................. 253
Energy monitor ..................... 118
LDA (Lane Departure Alert with steering control) .......... 238
Parking Support Brake function
(for static objects) ............... 279
Switching the display ............ 113
Warning message ................. 426 Navigation system
*
Odometer ................................. 111
Opener
Fuel door .............................. 215
Hood ..................................... 366
Trunk .................................... 138
Outside rear view mirrors ....... 164 Adjusting and folding ............ 164
BSM (Blind spot monitor)...... 300
Outside rear view mirror defoggers ........................... 309
Outside temperature
display.................................... 111
Overhead console ................... 324
Overheating ............................. 457
MN
O
*: Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.