2017 TOYOTA MIRAI overheating

1063. Instrument cluster
MIRAI_OM_USA_OM62023U■
Outside temperature display
●In the following situations, the correct outside temperature may not be dis-
played, or the display may take longer than normal to change.
• When stopped, or driving at low speeds (less than 16 mph [25 km/h])
• When the outside temperature has changed suddenly (at the entrance/
exit of a garage, tunnel, etc.)
● When “--” or “E” is displayed, the system may be malfunctioning.
Take your vehicle to your Toyota dealer.
■ Liquid crystal display
Small spots or light spots may appear on the display. This phenomenon is
characteristic of liquid crystal displays, and there is no problem continuing to
use the display.
■ Customization
The meter display can be customized on the multi-information display.
(Customizable features: →P. 439)
NOTICE
■To prevent damage to the fuel cell system and its components
This vehicle is equipped with high coolant temperature warning light
(→ P. 369), 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 stop the
vehicle in a safe place, and check the fuel cell system after it has cooled
completely.

1865-2. Driving procedures
MIRAI_OM_USA_OM62023U
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 brake engaged warning buzzer
A buzzer will sound if the vehicle is driven with the parking brake engaged.
“Release Parking Brake” is displayed on the multi-information display.
■ 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. 369
■ Usage in winter time
→P. 254
Operating instructions
NOTICE
■When parking the vehicle
Before you leave the vehicle, shift the shift position to P, set 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 brake components
overheating, which may affect braking performance and increase brake
wear.

2355-5. Using the driving support systems
5
Driving
MIRAI_OM_USA_OM62023U■
Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering 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.
■ 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 when vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-enabling will
not occur when vehicle speed increases
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will
operate:
● The shift position is in a position other than P or N (when starting 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 released.
■ Operating conditions of emergency brake signal
When the following three conditions are met, the emergency brake signal will
operate:
●The emergency flashers are off.
● Actual vehicle speed is over 35 mph (55 km/h).
● The brake pedal is depressed in a manner that cause the system to judge
from the vehicle deceleration that this is a sudden braking operation.
■ Automatic system cancelatio n of emergency brake signal
The emergency brake signal will turn off in any of the following situations:
● The emergency flashers are turned on.
● The brake pedal is released.
● The system judges from the vehicle deceleration that is not a sudden brak-
ing operation.

2676-1. Using the air conditioning system and defogger
6
Interior features
MIRAI_OM_USA_OM62023U
Heated steering wheel/seat heaters
Turn the heated steering wheel
on/off
The indicator light comes on when
the heated steering wheel is oper-
ating.
Heated steering wheel and seat heaters heat the side grips of the
steering wheel and seats, respectively.
WARNING
● Care should be taken to prevent injury if anyone in the following categories
comes in contact with the steering wheel and seats when the heater is on:
• Babies, small children, the elderly, the sick and the physically chal-
lenged
• Persons with sensitive skin
• Persons who are fatigued
• Persons who have taken alcohol or drugs that induce sleep (sleeping drugs, cold remedies, etc.)
● Observe the following precautions to prevent minor burns or overheating,
• Do not use seat heater more than necessary.
• Do not cover the seat with a blanket or cushion when using the seat
heater.
NOTICE
●Do not put heavy objects that have an uneven surface on the seat and do
not stick sharp objects (needles, nails, etc.) into the seat.
● To prevent 12-volt battery discharge, do not use the functions when the
fuel cell system is off.
Heated steering wheel

4068-2. Steps to take in an emergency
MIRAI_OM_USA_OM62023U
If your vehicle overheats
The following may indicate that your vehicle is overheating.
● The high coolant temperature warning light ( →P. 369) 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 Out put Power is Limited” (→P. 376) is dis-
played on the multi- information display
● Steam comes out from under the hood.
Label
Fuel cell stack coolant
reservoir Inverter coolant reservoir

451Alphabetical index
MIRAI_OM_USA_OM62023U
Child-protectors....................... 123
Cleaning ........................... 306, 310Aluminum wheels.................. 307
Exterior ................................. 306
Interior................................... 310
Seat belts .............................. 311
Clock ......................................... 280
Coat hooks ............................... 281
Condenser ................................ 325
Console box ............................. 273
Coolant Capacity ................................ 419
Checking ............................... 324
Preparing and checking Warning light ...................... 369
Cooling system ........................ 324 Fuel cell system
overheating......................... 406
Cruise control Dynamic radar cruise
control................................. 203
Cup holders.............................. 274
Curtain shield airbags ............... 37
Customizable features ............ 434
Daytime running light system .................................... 188
Defogger Outside rear view mirrors...... 261
Rear window ......................... 261
Windshield ............................ 261
Dimensions .............................. 416
Dinghy towing .......................... 171 Display
Drive information .................. 108
Dynamic radar cruise
control ................................ 203
Energy monitor ..................... 108
LDA
(Lane Departure Alert) ....... 216
Multi-information display ....... 107
Warning message ................ 376
Do-it-yourself maintenance .... 318
Door courtesy lights Location ................................ 269
Wattage ................................ 421
Door lock
Doors .................................... 120
Key ....................................... 398
Smart key system ................. 120
Wireless remote control ........ 120
Doors Automatic door locking
and unlocking systems ....... 123
Door glasses......................... 154
Door lock .............................. 122
Door windows ....................... 154
Open door warning buzzer ... 124
Open door warning light ....... 371
Outside rear view mirrors ..... 151
Rear door child-protector ...... 123
Drive information..................... 108
Driver’s seat belt reminder light ........................................ 371
Driver’s seat position memory .................................. 140
D
*: Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.

454Alphabetical index
MIRAI_OM_USA_OM62023U
Opening the fuel door ........... 198
Overheating .......................... 406
Power output restriction .......... 88
Power switch......................... 172
Precautions ............................. 82
Regenerative braking.............. 81
Road accident cautions .......... 92
Running out of fuel.................. 85
Service plugs .......................... 91
Sounds and vibrations ............ 80
Starting the system ............... 172
Traction battery air intake vent....................................... 85
Vehicle proximity notification
system ......... ......................... 84
Warning message ................. 376
Water release ....................... 173
Fuel consumption............ 111, 112
Fuel door .................................. 198 Refueling............................... 198
Fuses ........................................ 355
Garage door opener ................ 292
Gauges ..................................... 102
Glove box ................................. 273
Grocery bag hooks .................. 277 H
2O switch ............................... 173
Hands-free system
(for cellular phone)
*
Head restraints ........................ 145
Headlights ................................ 187 Automatic High Beam system .......... ...................... 190
Light switch ........................... 187
Replacing light bulbs ............ 358
Heated steering wheel ............ 267
Heaters Automatic air conditioning system .......... ...................... 258
Heated steering wheel .......... 267
Outside rear view mirrors ..... 261
Seat heaters ......................... 268
High mounted stoplight
Replacing light bulbs ............ 358
High-voltage components ........ 83
Hill-start assist control ........... 232
Hood ......................................... 320 Warning message................. 376
Hooks
Coat hooks ........................... 281
Grocery bag hooks ............... 277
Retaining hooks (floor mat) .... 26
Horn .......................................... 147
Hydrogen detectors .................. 87
Hydrogen-related components............................. 82
Hydrogen tanks ......................... 86 Capacity................................ 418
Location ............................ 78, 82
G
H

457Alphabetical index
MIRAI_OM_USA_OM62023U
Navigation system*
Odometer.................................. 102
OpenerFuel door............................... 200
Hood ..................................... 320
Trunk..................................... 126
Outside rear view mirrors ....... 151 Adjusting and folding ............ 151
BSM (Blind spot monitor) ...... 245
Outside rear view mirror defoggers ........................... 261
Outside temperature
display .................................... 102
Overhead console ................... 276
Overheating.............................. 406 P position switch ..................... 180
Parking brake........................... 186
Operation .............................. 186
Parking brake engaged warning buzzer/message ... 186
Warning light......................... 371
Parking lights........................... 187 Light switch ........................... 187
Replacing light bulbs ............ 358
PCS (Pre-Collision System).......... 238
Function ................................ 238
PCS switch ........................... 239
Warning light......................... 370
Warning message................. 376
Personal lights......................... 270 Switch ................................... 270
Wattage ................................ 421
Power control unit ..................... 83
Power easy access system .... 140
Power outlet ............................. 283
Power steering (Electric power steering) ...... 233
Warning light......................... 370
Power switch ........................... 172
Power windows ....................... 154 Jam protection function ........ 155
Operation .............................. 154
Window lock switch .............. 154
Pre-Collision System
(PCS) ...................................... 238 Function ................................ 238
PCS switch ........................... 239
Warning light......................... 370
Warning message................. 376
N
O
P
*: Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.