2023 TOYOTA MIRAI fuel

762-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
2-1.Fuel cell electric vehicle
The illustration is an example for explanation and may differ from the actual
item.
Fuel cell stack
Fuel cell converter and auxiliary inverter
Hydrogen tanks
Traction battery
Fuel cell electric ve hicle characteristics
Fuel cell electric vehicle efficiently use electricity, which i s
generated by a chemical reaction between hydrogen and oxy-
gen in a fuel cell stack, and electricity charged in a traction
battery to drive the electric motor (traction motor).
The fuel is H2 (compressed hydrogen gas), so the exhaust is
only water and water vapor. As they do not release emissions
such as CO
2 (Carbon Dioxide) and NOx (Nitrogen Oxides),
fuel cell electric vehicles are environmentally friendly vehi-
cles.
Fuel cell electric vehicle components

772-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
2
Fuel cell system
Electric motor (traction motor)
Tailpipe
*: If equipped
■Sounds unique to the fuel cell electric vehicle
Due to the design of y our fuel cell electric vehicle, there are various relays,
valves and pumps whic h under normal driving conditions will pro duce
sounds. This is a normal characte ristic of the vehicle and does not indicate a
malfunction.
Furthermore, these sounds may differ based on usage environment or con-
dition.
Noticeable soundsSource of the sounds
Clunking, clicking and
clackingOperation of relays and hydrogen tank valves
(Sounds may be heard wh en starting or stop-
ping the fuel cell system.)
Knocking
The parking lock is engaged
(Sounds may be heard when pressing the P
position switch or stopp ing the fuel cell sys-
tem.)
Whooshing, squealingGas is flowing through the nozzle and valves
(Sounds may be heard when filling the fuel.)
High pitch sound
 Pulsing sound
 Whooshing sound
Operation of the pumps
(In particular, sounds may be heard when
starting the fuel cell s ystem, accelerating from
a stop, or pressing the H
2O switch. The sound
may be louder when in Br mode or when the
vehicle decelerates during dynamic radar
cruise control.)
 Humming sound
 High pitch soundOperation of the motor
(In particular, sounds may be heard when
accelerating or decelerating.)
Blowing and draining
sound
Exhaust water or air is being purged
May also occur periodically while parked when
it is cold to p revent freezing.
(Sounds may be hear d when vehicle is
stopped, fuel cell system is stopped or while
parked)

782-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
■Maintenance, repair, recycling,
and disposal
Contact your Toyota dealer regard-
ing maintenance, repair, recycling,
and disposal. Do not dispose of the
vehicle or any of its components
yourself.
The electric motor (traction
motor) allows smooth, powerful
takeoff and acceleration. This
vehicle drives similarly to a gas-
oline vehicle without any special
actions by the driver. ( P.169)
As there are no engine sounds
and the vehicle is quiet, opera-
tion noises unique to fuel cell
electric vehicle components
may be heard. ( P.77)
■Regenerative braking
In the following si tuations, the vehi-
cle generates electricity from the
deceleration of the vehicle while
driving.
●The accelerator pedal is released
while driving with the shift position
in D.
●The brake pedal is depressed
while driving with the shift position
in D.
■Charging the traction battery
Because electricity generated by the
fuel cell stack and regenerative
braking charges the traction battery,
the battery does not need to be
charged from an outside source.
However, if the vehicle is left parked
for a long time, the traction battery
will slowly discharge. For this rea-
son, be sure to drive the vehicle at
least once every few months for at
least 30 minutes or 10 miles (16
km). If the traction ba
ttery becomes fully
discharged and yo u are unable to
start the fuel cell system, contact
your Toyota dealer.
■Charging the 12-volt battery
 P.487
■Sounds and vibrations specific
to a fuel cell e lectric vehicle
Because there is no engine sound
or vibration, it is easy to mistake the
fuel cell electric vehicle for being off
when it is actually still running, as
indicated by the “READY” indicator
being illumina ted. For safety, make
sure to always shift the shift position
to P and apply the parking brake
when parked.
The system may behave differ-
ently on cold days as it may be
performing a special cold-start
process to improve the start up
performance. ( P.180)
Operation noises ( P.77),
purge process ( P.182), etc.,
may differ from usual. However,
this is not a malfunction.
Compressed hydrogen gas fuel
can be filled at hydrogen sta-
tions.
More information about hydrogen
fuel and fueling can be found in the
“Opening the fuel door” section of
this manual. ( P.210)
Driving the vehicle
Fuel cell system
Fuel filling

792-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
2
Fuel cell system
Fuel cell electric vehicles do not
have engine sounds like gaso-
line vehicles. Therefore, a
sound that changes in accor-
dance with the driving speed,
will be played in order to warn
people nearby of the vehicle’s
approach. The sound will stop
when the vehicle speed
exceeds approximately 23 mph
(37 km/h).
■How to hear the warning
In the following ca ses, the acoustic
vehicle alerting system may be diffi-
cult for surrounding people to hear.
●In very noisy areas
●In the wind or the rain
Also, as the acoustic vehicle alerting
system is installed on the front of the
vehicle, it may be m ore difficult to
hear from the rear of the vehicle
compared to the front.
*: This function can only be used in
the mainland U.S.A. It cannot be
used in other states and territo-
ries, including Alaska and Hawaii.
This system operates based on
the driving situation and traffic
information to enhance fuel
economy.
For details about Predictive effi-
cient drive, refer to “MULTIME-
DIA OWNER’S MANUAL”.
■Predictive deceleration sup-
port
 When the vehicle approaches
to predictive deceleration sup-
port points registered in the
navigation system, the refer-
ence operation range of
the ECO Accelerator Guid-
ance ( P.108) on the multi-
information display will be
turned off to encourage the
driver to reduce excessive
acceleration.
With 8-inch multi-information
display
With 12.3-inch multi-informa-
tion display
Acoustic vehicle alerting
system
Predictive efficient drive
(vehicles with navigation
system)
*

802-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
The regenerative braking
force will be increased
according to the driving condi-
tions to more efficiently
charge the traction battery
after the accelerator pedal is
released.

812-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
2
Fuel cell system
■Hydrogen-related components
The fuel cell electric vehicle has hydrogen tanks (10150 psi [7 0 MPa,
714 kgf/cm
2, 700 bar]), fuel cell stack, and hydrogen pipelines as
hydrogen-related components. Pay attention to all warning label s
attached to the vehicle.
The illustration is an example fo r explanation and may differ from the actual
item.
Warning label
Fuel cell stack (fuel cell and hydrogen pump)
Hydrogen detectors
Hydrogen tanks
Hydrogen tank valves
Hydrogen pipelines
Hydrogen supply unit
*: If equipped
Fuel cell electric vehicle precautions
System components

822-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
■High-voltage and high-temperature components
The fuel cell electric vehicle has high-voltage components (abo ut
650 V maximum) such as a fuel c ell stack, traction battery, power
control unit, fuel cell converter, high-voltage cables (which a re distin-
guished from low-voltage cables b y their orange covers), electric
motor (traction motor), etc., and high-temperature parts such a s the
radiator for cooling. Pay attention to all warning labels attached to
the vehicle.
This diagram is for illustrative purposes only and may differ f rom the actual
vehicle.
Warning label
Radiator for inverter cooling
Radiator for fuel cell stack cooling
Fuel cell water pump
Fuel cell converter and auxiliary inverter
Power control unit
Cabin coolant heater
Traction battery
Service plug

832-1. Fuel cell electric vehicle
Owners Manual_USA_M62064_en
2
Fuel cell system
Electric motor (traction motor)
High-voltage cables (orange)
Fuel cell stack (fuel cell and hydrogen pump)
Air compressor
Air conditioning compressor
■If “Hydrogen Leakage Detected
Visit Your Dealer” is displayed
on the multi-information display
A small amount of hydrogen gas
may be leaking. Have the vehicle
inspected immediately at the near-
est Toyota dealer.
■If “FCV System Shutdown Due
to Hydrogen Leakage Stop in a
Safe Place See Owner’s Man-
ual” is displayed on the multi-
information display
●Hydrogen gas may be leaking.
When hydrogen gas is leaking or
some other malfunction is
detected: P. 8 7
●The air conditioning system will
shut off automatically.
■Running out of fuel
When the vehicle has run out of fuel
and the fuel cell system cannot be
started, refuel the vehicle until the
low fuel level warning light ( P.460)
turns off before try ing to restart. It
may not be able to restart if the refu-
eled amount is too low.
■Fuel cell stack
●Depending on the usage environ-
ment, the fuel ce ll power output
may decline over the life of the
vehicle. However, this will have
almost no effect on driving perfor-
mance.
●In the following situations, the fuel
cell power output may decline
faster than normal driving:
• Extended use in areas with high
amounts of dust
• Extended use in areas with high levels of sulfur (such as volcanoes
or hot springs).
• Extended use in areas with high concentrations o f the following
substances:
-Organic solvents, such as paint and
thinner
-Amine-related materials such as
ammonia
-Chlorinated substances such as
salt air and snow-melting agent
• Salt water gets into the air cleaner filter
It is recommended to replace the
air cleaner filter and clean the sur-
rounding components. Have the
vehicle inspected at your Toyota
dealer
• The number of times the fuel cell system is started and stopped is
excessively high
• Extended use in freezing tem- peratures
• Fill fuel with impurities which do not follow ISO-14687
■Hydrogen tanks
●The hydrogen tanks are the high-
pressure storage containers that
are filled with co mpressed hydro-
gen gas. The vehicle can be refu-
eled at hydrogen stations.
●The hydrogen tanks have an expi-
ration date. Vehicles with expired
hydrogen tanks must not be
driven or refueled until the hydro-
gen tanks are replaced. The expi-
ration date is written on the inside
of the fuel door. Consult your Toy-
ota dealer.
●Consult your Toyota dealer if the