cooling TOYOTA MIRAI 2017 1.G User Guide

4078-2. Steps to take in an emergency
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When trouble arises
■If the high coolant temperature warning light comes on or
flashes
Stop the vehicle in a safe place and turn off the air conditioning sys-
tem, and then stop the fuel cell system.
If you see steam or coolant leaks:
Carefully lift the hood after the steam subsides.
If you do not see steam or coolant leaks:
Carefully lift the hood.
After the fuel cell system has
cooled down sufficiently,
inspect the hoses and radiator
core (radiator) for any leaks.
Fuel cell stack coolant sub
radiator
Fuel cell stack coolant radia-
tor
Electric cooling fans
If a large amount of coolant
leaks, immediately contact your
Toyota dealer.
NOTICE
Correction procedures
The fuel cell stack coolant is exclusive for
fuel cell stack usage. Damage may occur
when water or any other type of coolant
is used, so never use any other fluid.
If the fuel cell stack coolant is low, imme-
diately contact your Toyota dealer.
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4098-2. Steps to take in an emergency
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When trouble arises
■If “FC System Overheat Output Power is Limited” is displayed
on the multi-information displayStop the vehicle in a safe place and turn off the air conditioning
system, and then stop the fuel cell system.
If you see steam or coolant leaks:
Carefully lift the hood after the steam subsides.
If you do not see steam or coolant leaks:
Carefully lift the hood.
After the fuel cell system has
cooled down, inspect the
hoses and radiator core
(radiator) for any leaks.
Inverter coolant radiator
Electric cooling fans
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
The inverter coolant level is
satisfactory if it is between
the “FULL” and “LOW” lines
on the reservoir.Inverter coolant reservoir
“FULL”
“LOW”
Add inverter coolant if neces-
sary.
Water can be used in an emer-
gency if inverter coolant is
unavailable.
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4108-2. Steps to take in an emergency
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Start the fuel cell system and turn the air conditioning system on
to check that the radiator cooling fans operate and to check for
coolant leaks from th e radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating by checking
the fan sound and air flow. If it is difficult to check these, turn the air con-
ditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the fuel cell system immedi ately and contact your Toyota
dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Toyota dealer.
WARNING
■ When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
● If steam is seen coming from under the hood, do not open the hood until
the steam has subsided. The motor compartment may be very hot.
● After the fuel cell system has been turned off, check that the “READY”
indicator is off.
When the fuel cell system is operating, the cooling fans may suddenly
operate even if the fuel cell system stops. Do not touch or approach rotat-
ing parts such as the fans, which may lead to fingers or clothing (espe-
cially a tie, a scarf or a muffler) getting caught, resulting in serious injury.
● Do not loosen the coolant reservoir caps or radiator cap, while the fuel cell
system and radiator are hot.
High temperature steam or coolant could spray out.
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4118-2. Steps to take in an emergency
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When trouble arises
NOTICE
■When adding inverter coolant
Add coolant slowly after the fuel cell system has cooled down sufficiently.
Adding inverter cool coolant to a hot fuel cell system too quickly can cause
damage to the fuel cell system.
■ To prevent damage to the cooling system
Observe the following precautions:
● Avoid contaminating the coolant with foreign matter (such as sand or dust
etc.).
● Do not use any coolant additive with inverter coolant.
● For replacement of the fuel cell stack coolant, contact your Toyota dealer.
● Do not use water or any other coolant when refilling the fuel cell stack
coolant. Also, do not use any additive agents for the coolant.

4199-1. Specifications
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Vehicle specifications
*: The fluid capacity is a reference quantity.If replacement is necessary, contact your Toyota dealer.
Cooling system
Capacity*
Fuel cell
stack 20.7 qt. (19.6 L, 17.2 Imp.qt.)
Inverter 5.0 qt. (4.7 L, 4.1 Imp.qt.)
Coolant
type
Fuel cell
stack“Toyota Genuine FC Stack Coolant”
• In order to safely cool the fuel cell stack,
which is at high voltages, the fuel cell stack
coolant is an exclusive high insulation prod-
uct.
• Never use water or other kinds of coolants as they will cause damage.
• Coolant changes are unnecessary.
• Do not reuse coolant that has been removed from the radiator.
• Coolant is colorless.
• Consult your Toyota dealer about replenish- ing or changing the fuel cell stack coolant.
Inverter Use either of the following:
• “Toyota Super Long Life Coolant”
• A similar high-quality ethylene glycol-based
non-silicate, non-amine, non-nitrite, and
non-borate coolant with long-life hybrid
organic acid technology
Do not use plain water alone.
NOTICE
The fuel cell stack coolant is exclusive for
fuel cell stack usage. Damage may occur
when water or any other type of coolant
is used, so never use any other fluid.
If the fuel cell stack coolant is low, imme-
diately contact your Toyota dealer.

451Alphabetical index
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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”.