2023 TOYOTA MIRAI battery

4668-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
■If a message that indicates the
need for visiting your Toyota
dealer is displayed
The system or part shown on the
multi-information display is malfunc-
tioning. Have the vehicle inspected
by your Toyota dealer immediately.
■If a message that indicates the
need for referring to Owner’s
Manual is displayed
●If any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal-
function. Have the vehicle
inspected by you r Toyota dealer
immediately.
• “Smart Key System Malfunction
See Owner’s Manual”
• “P Switch Malfunction Apply Park- ing Brake Securely When Parking
See Owner’s Manual”
• “Shift System Malfunction Apply Parking Brake Securely When
Parking See Owner’s Manual”
• “Shift System Unavailable Apply Parking Brake Securely When
Parking See Owner’s Manual”
• “Shift System Malfunction See Owner’s Manual”
• “Shift System Malfunction Stop in a Safe Place See Owner’s Man-
ual”
• “Battery Low Shifting Unavailable See Owner’s Manual”
• “FCV system malfunction”
• “Traction battery system malfunc-
tion”
• “Accelerator System Malfunction”
●If any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal-
function. Immediat ely stop the
vehicle and contact your Toyota
dealer.
• “Braking Power Low Stop in a Safe Place See Owner’s Manual”
• “FCV System Shutdown Due to
Hydrogen Leakage Stop in a Safe
Place See Owner’s Manual”
●If “FCV system stopped” is shown
on the multi-information display,
the vehicle may have run out of fuel. Stop the vehicle in a safe
place and, if the fuel level is low,
refuel the vehicle. (
P.83)
●If “Low Auxiliary Battery See
Owner’s Manual” is shown,
• When the display goes off after several seconds (displays for
about 6 seconds): Maintain the
fuel cell system operation for more
than 15 minutes and charge the
12-volt battery.
• When the display does not go off: Start up the fuel cell system using
the procedures: P. 4 8 5
●If “Maintenance Required for Trac-
tion Battery Cooling Parts See
Owner’s Manual” is shown, the fil-
ters may be clogged, the air intake
vents may be blocked, or there
may be a gap in the duct. There-
fore, perform the following correc-
tion procedure.
• Cleaning the traction battery air intake vents ( P.433)
If the warning message is shown
even if the vents are cleaned,
have the vehicle inspected by
your Toyota dealer.
■If “Ion Filter Maintenance
Required Visit Your Dealer” is
displayed
Ion filter replacement is necessary.
Contact your Toyota dealer.
NOTICE
■If “Low Auxiliary Battery See
Owner’s Manual” is displayed
frequently
The 12-volt battery may have
deteriorated. As the battery may
discharge in this state when left
unattended, have the battery
inspected by you r Toyota dealer.

4678-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
8
When trouble arises
NOTICE
■If “Maintenance Required For
Traction Battery At Your
Dealer” is displayed
This message indi cates that the
traction battery may require
inspection or replacement. Have
the vehicle inspected by your Toy-
ota dealer immediately.
Do not continue driving the vehi-
cle, as the fuel cell system may
become not able to be started
again.
If you have a flat tire
Your vehicle is not equipped
with a spare tire, but instead
is equipped with an emer-
gency tire puncture repair
kit.
A puncture caused by a nail
or screw passing through
the tire tread can be
repaired temporarily using
the emergency tire puncture
repair kit. (The kit contains a
bottle of sealant. The seal-
ant can be used only once
to temporarily repair one
tire without removing the
nail or screw from the tire.)
Depending on the damage,
this kit cannot be used to
repair the tire. ( P.468)
After temporarily repairing
the tire with the kit, have the
tire repaired or replaced by
your Toyota dealer. Repairs
conducted using the emer-
gency tire puncture repair
kit are only a temporary
measure. Have the tire
repaired and replaced as
soon as possible.
WARNING
■If you have a flat tire
Do not continue driving with a flat
tire.
Driving even a short distance with
a flat tire can damage the tire and
the wheel beyond repair, which
could result in an accident.

4808-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
One of the following may be the
cause of the problem:
The electronic key may not be
functioning properly.
( P.482)
 There may not be sufficient
fuel in the vehicle’s tank.
Refuel the vehicle.
 The fuel door may be open.
( P.212)
 There may be a malfunction
in the immobilizer system.
( P. 7 0 )
 There may be a malfunction
in the shift control system.
*
( P.183, 465)
 The fuel cell system may be
malfunctioning due to an elec-
trical problem such as elec-
tronic key battery depletion or
a blown fuse. However, depending on the type of mal-
function, an interim measure
is available to start the fuel
cell system. (
P.481)
 There is a possibility that the
temperature of the traction
battery is extremely low
(approximately below -22˚F [-
30˚C]). ( P.85, 180)
 It is possible the fuel cell sys-
tem is frozen. ( P.180)
*: It may not be possible to shift the
shift position from P.
One of the following may be the
cause of the problem:
 The 12-volt battery may be
discharged. ( P.485)
 The 12-volt battery terminal
connections may be loose or
corroded. ( P.413)
One of the following may be the
cause of the problem:
 One or both of the 12-volt bat-
tery terminals may be discon-
nected. ( P.413)
If the fuel cell system
will not start
Reasons for the fuel cell
system not starting vary
depending on the situation.
Check the following and
perform the appropriate
procedure:
The fuel cell system will
not start even though the
correct starting procedure
is being followed.
( P.180)
The interior lights and
headlights are dim, or the
horn does not sound or
sounds at a low volume.
The interior lights and
headlights do not turn on,
or the horn does not
sound.

4818-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
8
When trouble arises
 The 12-volt battery may be
discharged. ( P.485)
Contact your Toyot a dealer if the
problem cannot be repaired, or if
repair procedures are unknown.
When the fuel cell system does
not start, the following steps can
be used as an interim measure
to start the fuel cell system if the
power switch is functioning nor-
mally.
Do not use this starting proce-
dure except in cases of emer-
gency.
1 Pull the parking brake switch
to check that the parking
brake is set. ( P.191)
Parking brake indicator will come
on.
2 Turn the power switch to
ACC.
3 Press and hold the power
switch for about 15 seconds
while depressing the brake
pedal firmly.
Even if the fuel cell system can
be started using the above
steps, the system may be mal-
functioning. Have the vehicle
inspected by your Toyota dealer.
Starting the fuel cell sys-
tem in an emergency
If you lose your keys
New genuine mechanical
keys can be made by your
Toyota dealer using another
mechanical key and the key
number stamped on your
key number plate.
Keep the plate in a safe
place such as your wallet,
not in the vehicle.
NOTICE
■When an electronic key is lost
If the electronic key remains lost,
the risk of vehicle theft increases
significantly. Visit your Toyota
dealer immediately with all
remaining electronic keys that
were provided with your vehicle.

4828-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
1Remove the cover inside the
trunk.
2 After removing the cover, pull
the lever to unlock the fuel
door and it will be ready to
open as usual.
■When the electronic key does
not work properly
●Make sure that the smart key sys-
tem has not been deactivated in
the customization setting. If it is
off, turn the function on.
●Check if battery-saving mode is
set. If it is set, cancel the function.
( P.137)
If the fuel door cannot
be opened
If the fuel door opener
switch cannot be operated,
the following procedure can
be used to open the fuel
door.
Opening the fuel door
If the electronic key
does not operate prop-
erly
If communication between
the electronic key and vehi-
cle is interrupted ( P.138)
or the electronic key cannot
be used because the battery
is depleted, the smart key
system and wireless remote
control cannot be used. In
such cases, the doors and
trunk can be opened and
the fuel cell system can be
started by following the pro-
cedure below.
NOTICE
■In case of a smart key system
malfunction or other key-
related problems
Take your vehicle with all the elec-
tronic keys provided with your
vehicle to your Toyota dealer.

4848-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
1With the P shift position
selected, firmly depress the
brake pedal.
2 Touch the Toyota emblem
side of the electronic key to
the power switch.
When the electronic key is
detected, a buzzer sounds and the
power switch will turn to ON.
When the smart key system is
deactivated in customization set-
ting, the power switch will turn to
ACC.
3Firmly depress the brake
pedal and check that is
shown on the multi-informa-
tion display.
4 Press the power switch.
In the event that the fuel cell
system still cannot be started,
contact your Toyota dealer.
■Stopping the fuel cell system
Set the parking brake, shift the shift
position to P and press the power
switch as you no rmally do when
stopping the fuel cell system.
■Electronic key battery
As the above proce dure is a tempo-
rary measure, it is recommended
that the electronic key battery be
replaced immediatel y when the bat-
tery is depleted. ( P.436)
■Alarm (For Canada)
Using the mechanical key to lock
the doors will not set the alarm sys-
tem. If a door is unlocked using the
mechanical key when the alarm sys-
tem is set, the alarm may be trig-
gered. ( P.71)
■Changing power switch modes
Release the brake pedal and press
the power switch in step 3 above.
The fuel cell system does not start
and modes will be changed each
time the switch is pressed. ( P.183)
Starting the fuel cell sys-
tem

4858-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
8
When trouble arises
If you have a set of jumper (or
booster) cables and a second
vehicle with a 12-volt battery,
you can jump start your vehicle
by following the steps below.
1 Confirm that the electronic
key is being carried.
When connecting the jumper (or
booster) cables, depending on the
situation, the ala rm may activate and doors locked. (
P. 7 2 )
2 Open the hood. Remove the
fuse box cover. ( P.406)
Push the tabs in and lift the lid off.
3 Open the exclusive jump
starting terminal cover.
4 Connect a positive jumper cabl e clamp to on your vehicle and
connect the clamp on the other end of the positive cable to on
the second vehicle. Then, connect a negative cable clamp to
on the second vehicle and connect the clamp at the other end of
the negative cable to .
If the 12-volt batter y is
discharged
The following procedures
may be used to start the fuel
cell system if the 12-volt
battery is discharged.
You can also call your Toy-
ota dealer or a qualified
repair shop.
Restarting the fuel cell
system

4868-2. Steps to take in an emergency
Owners Manual_USA_M62064_enWhen connecting to an unpaint
ed metallic point , make the connection
after checking the surrounding a rea. Also, do not make any connections
where parts nearby may interfere.
Use jumper cables that can reach the specified terminals and connecting
point.
Exclusive jump starting terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery term inal (second vehicle)
Metallic point shown in the illustration
5 Start the engine of the sec-
ond vehicle. Increase the
engine speed slightly and
maintain at that level for
approximately 5 minutes to
recharge the 12-volt battery
of your vehicle.
6 Open and close any of the
doors of your vehicle with the
power switch off.
7 Maintain the engine speed of
the second vehicle and start
the fuel cell system of your
vehicle by turning the power
switch to ON. 8
Make sure the “READY” indi-
cator comes on. If the indica-
tor does not come on, contact
your Toyota dealer.
9 Once the fuel cell system has
started, remove the jumper
cables in the exact reverse
order from which they were
connected.
10Close the exclusive jump starting terminal cover and
install the fuse box cover.
Once the fuel cell system starts,
have the vehicle inspected at
your Toyota dealer as soon as
possible.