2020 TOYOTA MIRAI Owners Manual (in English)

4578-2. Steps to take in an emergency
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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

4588-2. Steps to take in an emergency
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If the high coolant temperature warning light comes on or
flashes
Stop the vehicle in a safe place and turn off the air condition
ing sys-
tem, and then stop t he 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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2
3

4598-2. Steps to take in an emergency
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When trouble arises
The fuel cell stack coolant level
is satisfactory if it is between
the “FULL” and “LOW” lines on
the reservoir.
Fuel cell stack coolant reser-
voir
“FULL” line
“LOW” line
If the amount of fuel cell stack coolant is low:
Immediately contact your Toyota dealer.
If the amount of fuel cell st ack coolant is not low:
Have the vehicle inspected at the neare st Toyota dealer.
Even if the fuel cell stack cool-
ant is low, do not refill it.4

4608-2. Steps to take in an emergency
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If “FC System Overheat Output P
ower is Limited” is displayed
on the multi-information display
Stop the vehicle in a safe place and turn off the air conditioning
system, and then stop th e 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 cool ant if neces-
sary.
Water can be used in an emer-
gency if inverter coolant is
unavailable.
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4618-2. Steps to take in an emergency
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When trouble arises
Start the fuel cell system and turn the air conditioning system on
to check that the radiator coo ling fans operate and to check fo r
coolant leaks from t he 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 b y 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 immed iately and contact your Toyota
dealer.
If the fans are operating:
Have the vehicle inspected at the neare st Toyota dealer.
WARNING
■When inspecting under th e 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 ho od 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 app roach 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 i n 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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4628-2. Steps to take in an emergency
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NOTICE
■When adding inverter coolant
Add coolant slowly after the fuel cell system has cooled down s ufficiently.
Adding inverter cool coolant to a hot fuel cell system too quic kly 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 sa nd 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 c ell stack
coolant. Also, do not use any additive agents for the coolant.

4638-2. Steps to take in an emergency
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When trouble arises
If the vehicle becomes stuck
Set the parking brake and stop the fuel cell system.
Remove the mud, snow or sand from around the front wheels.
Place wood, stones or some other material under the front wheel s
to help provide traction.
Restart the fuel cell system.
Shift the shift position to D or R and release the parking brak e.
Then, while exercising caution, depress the accelerator pedal.
■When it is difficult to free the vehicle
Carry out the following procedures if the tires spin or the vehicle
becomes stuck in mud, dirt or snow:
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2
3
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Press to turn off TRAC.
WARNING
■When attempting to f ree a stuck vehicle
If you choose to push the vehicle back and forth to free it, ma ke sure the
surrounding area is clear to avoid striking other vehicles, obj ects or people.
The vehicle may also lunge forward or lunge back suddenly as it becomes
free. Use extreme caution.
■ When shifting the shift position
Be careful not to shift the shift position with the accelerator pedal
depressed.
This may lead to unexpected rapid acceleration of the vehicle t hat may
cause an accident resulting in death or serious injury.

4648-2. Steps to take in an emergency
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NOTICE
■To avoid damaging the transmission and other components
● Avoid spinning the front wheels and depressing the accelerator pedal
more than necessary.
● If the vehicle remains stuck even after these procedures are pe rformed,
the vehicle may require towing to be freed.