2023 TOYOTA MIRAI battery

4878-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
8
When trouble arises
■Starting the fuel cell system
when the 12-volt battery is dis-
charged
The fuel cell system cannot be
started by push-starting.
■To prevent 12-volt battery dis-
charge
●Turn off the headlights and the
audio system while the fuel cell
system is off.
●Turn off any unnecessary electri-
cal components when the vehicle
is running at a low speed for an
extended period, such as in heavy
traffic.
■When the 12-volt battery is
removed or discharged
●Information stor ed in the ECU is
cleared. When the 12-volt battery
is depleted, have the vehicle
inspected at you r Toyota dealer.
●Some systems may require initial-
ization. ( P.526)
●If the 12-volt battery discharges, it
may not be possible to shift the
shift position to other positions.
In this case, the vehicle cannot be
towed without lifting both rear
wheels because the rear wheels will
be locked.
■When removing the 12-volt bat-
tery terminals
When the 12-volt battery terminals
are removed, the information stored
in the ECU is cleared. Before
removing the 12-volt battery termi-
nals, contact your Toyota dealer.
■Charging the 1 2-volt battery
The electricity stor ed in the 12-volt
battery will discharge gradually even
when the vehicle is not in use, due
to natural discharge and the drain-
ing effects of certain electrical appli-
ances. If the vehicle is left for a long
time, the 12-volt battery may dis-
charge, and the fuel cell system
may be unable to s tart. (The 12-volt battery recharges automatically
while the fuel cell
system is operat-
ing.)
■When recharging or replacing
the 12-volt battery
●In some cases, it may not be pos-
sible to unlock the doors using the
smart key system when the 12-
volt battery is discharged. Use the
wireless remote c ontrol or the
mechanical key to lock or unlock
the doors.
●The fuel cell system may not start
on the first attempt after the 12-
volt battery has recharged but will
start normally after the second
attempt. This is not a malfunction.
●The power switch mode is memo-
rized by the vehicle. When the 12-
volt battery is reconnected, the
system will return to the mode it
was in before the 12-volt battery
was discharged. Before discon-
necting the 12-volt battery, turn
the power switch off.
If you are unsure what mode the
power switch was in before the
12-volt battery discharged, be
especially careful when recon-
necting the 12-volt battery.
●When the 12-volt battery is recon-
nected, start the fuel cell system,
depress the brake pedal, and con-
firm that it is possible to shift into
each shift position.
●If the battery is removed or the ter-
minals disconnected without oper-
ating the water release function
during cold weather, the vehicle
may not start due to the fuel cell
system being frozen. To prevent
this, operate th e water release
function before removing the bat-
tery or disconnecting the termi-
nals. ( P.196)

4888-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
■When replacing the 12-volt bat-
tery
●Use a Central Degassing type 12-
volt battery (European Regula-
tions).
●Use a 12-volt battery with the
same case size as the previous
12-volt battery and an equivalent
20 hour rate capacity (20HR) or
greater.
• If the sizes differ, the 12-volt bat- tery cannot be properly secured.
• If the 20 hour rate capacity is low,
even if the time period where the
vehicle is not used is a short time,
the 12-volt battery may discharge
and the fuel cell system may not
be able to start.
●Use a 12-volt battery with a han-
dle. If a 12-volt b attery without a
handle is used, removal is more
difficult.
●After replacing, firmly attach the
following items to the exhaust hole
of the 12-volt battery.
• Use the exhaust hose that was
attached to the 12-volt battery
before replacing an d confirm that
it is firmly connected to the hole
section of t he vehicle.
• Use the exhaust hole plug included with the 12-volt battery
replaced or the one installed on
the 12-volt battery prior to the
replacement. (Depending on the
12-volt battery to be replaced, the
exhaust hole may be plugged.)
Exhaust hole plug
Exhaust hole
Exhaust hose For details, consult your Toyota
dealer.
WARNING
■When removing the 12-volt
battery terminals
Always remove the negative (-)
terminal first. If the positive (+) ter-
minal contacts any metal in the
surrounding area when the posi-
tive (+) terminal is removed, a
spark may occur, leading to a fire
in addition to ele ctrical shocks
and death or serious injury.
■Avoiding 12-volt battery fires
or explosions
Observe the following precautions
to prevent accidentally igniting the
flammable gas that may be emit-
ted from the 12-volt battery:
●Make sure each jumper cable is
connected to the correct termi-
nal and that it is not unintention-
ally in contact with any other
than the intended terminal.
●Do not allow the other end of
the jumper cable connected to
the “+” terminal to come into
contact with any other parts or
metal surfaces in the area, such
as brackets or unpainted metal.
●Do not allow the + and - clamps
of the jumper cables to come
into contact with each other.
●Do not smoke, use matches,
cigarette lighter s or allow open
flame near the 1 2-volt battery.
■12-volt battery precautions
The 12-volt battery contains poi-
sonous and corrosive acidic elec-
trolyte, while related parts contain
lead and lead compounds.
Observe the following precautions
when handling the 12-volt battery:

4898-2. Steps to take in an emergency
Owners Manual_USA_M62064_en
8
When trouble arises
WARNING
●When working with the 12-volt
battery, always wear safety
glasses and take care not to
allow any battery fluids (acid) to
come into contact with skin,
clothing or the vehicle body.
●Do not lean over the 12-volt bat-
tery.
●In the event that battery fluid
comes into contact with the skin
or eyes, immediately wash the
affected area with water and
seek medical attention. Place a
wet sponge or cloth over the
affected area until medical
attention can be received.
●Always wash your hands after
handling the 12-volt battery sup-
port, terminals, and other bat-
tery-related parts.
●Do not allow child ren near the
12-volt battery.
■After recharging the 12-volt
battery
Have the 12-volt battery
inspected at your Toyota dealer
as soon as possible.
If the 12-volt battery is deteriorat-
ing, continued use may cause the
12-volt battery to emit a malodor-
ous gas, which may be detrimen-
tal to the health of passengers.
■When replacing the 12-volt
battery
●When the vent plug and indica-
tor are close to the hold down
clamp, the battery fluid (sulfuric
acid) may leak.
●For information regarding 12-
volt battery rep lacement, con-
tact your Toyota dealer.
●After replacing, s ecurely attach
the exhaust hose and exhaust
hole plug to the exhaust hole of
the replaced 12-volt battery. If
not properly installed, gases
(hydrogen) may leak into the
vehicle interior, and there is the
possible danger of the gas ignit-
ing and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan.
■When connecting jumper
cables
Make sure to connect jumper
cables to the specified terminals
and connecting point. Failure to
do so may adversely affect the
electronic devices or damage to
them.
■To prevent damaging the
vehicle
The exclusive jump starting termi-
nal is to be used when charging
the 12-volt battery from another
vehicle in an emergency. It cannot
be used to jump start another
vehicle.

4989-1. Specifications
Owners Manual_USA_M62064_en
Electric motor (traction motor)
Ty p ePermanent magnet synchronous
motor
Maximum output134 kW
Maximum torque221.3 ft•lbf (300 N•m, 30.6 kgf•m)
Traction battery
Ty p eLithium-ion battery
Voltage3.7 V/cell
Capacity4.0 Ah
Quantity84 cells
Nominal voltage310.8 V
Cooling system
Capacity*
Fuel cell
stack17.3 qt. (16.4 L, 14.4 Imp. qt.)
Inverter4.2 qt. (4.0 L, 3.5 Imp. qt.)

5009-1. Specifications
Owners Manual_USA_M62064_en
*: The fluid capacity is a reference quantity.If replacement is necessary, contact your Toyota dealer.
*1: Minimum pedal clearance when depressed with a force of 112 lbf (500 N, 51 kgf) while the fuel cell system is operating.
When performing the brake pedal i nspection, also be sure to check that
Electrical system (12-volt battery)
Open voltage at 68°F (20°C):
12.0 V or higher
(Turn the power switch off and turn on the
high beam headlights for 30 seconds.)
Charging rates
Quick charge
Slow charge
15 A max.
5 A max.
Transmission
Fluid capacity*5.9 qt. (5.6 L , 4.9 Imp. qt.)
Fluid typeToyota Genuine ATF WS
NOTICE
■Transmission fluid type
Using transmission fluid other than the above type may cause ab normal
noise or vibration, or damage th e transmission of your vehicle.
Brakes
Pedal clearance*14.0 in. (102 mm) Min.
Pedal free play0.04  0.24 in. (1  6 mm)
Brake pad wear limit0.04 in. (1 mm)
Parking brake lin ing wear limit0.04 in. (1 mm)
Parking brake indicator*2
When pulling the parking brake switch for
1 to 2 seconds: comes on
When pushing the parking brake switch for
1 to 2 seconds: turns off
Fluid typeFMVSS No.116 DOT 3 or SAE J1703
FMVSS No.116 DOT 4 or SAE J1704

5079-1. Specifications
Owners Manual_USA_M62064_en
9
Vehicle specifications
Occupant distribution
Distribution of occupants in a vehicle as
specified in the third column of Table 1
*
below
Production options weight
The combined weight of installed regular
production options weighing over 5 lb. (2.3
kg) in excess of the standard items which
they replace, not previously considered in
curb weight or accessory weight, including
heavy duty brakes, ride levelers, roof rack,
heavy duty 12-volt battery, and special trim
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated
Rim diameter (Wheel diame-
ter)Nominal diameter o f the bead seat
Rim size designationRim diameter and width
Rim type designationThe industry manufacturer’s designation
for a rim by style or code
Rim widthNominal distance between rim flanges
Vehicle capacity weight (Total
load capacity)The rated cargo and luggage load plus 150
lb. (68 kg) times the vehicle’s designated
seating capacity
Vehicle maximum load on the
tire
The load on an individua l tire that is deter-
mined by distributing to each axle its share
of the maximum loaded vehicle weight,
and dividing by two
Vehicle normal load on the tire
The load on an individua l tire that is deter-
mined by distributing to each axle its share
of curb weight, accessory weight, and nor-
mal occupant weight (distributed in accor-
dance with Table 1
* below), and dividing by
two
Weather sideThe surface area of the rim not covered by
the inflated tire
Bead
The part of the tire that is made of steel
wires, wrapped or reinforced by ply cords
and that is shaped to fit the rim
Tire related termMeaning

5129-2. Customization
Owners Manual_USA_M62064_en
9-2.Customization
■Changing by using the
meter control switches
1 Press or to select .
2 Operate the meter control
switches to select the desired
item to be customized.
3 According to the display,
select the desired setting and
then press .
To go back to the previous screen
or exit the customize mode, press
.
■Changing by using the mul-
timedia system
1 Select on the main menu
screen. 2
Select “Vehicle customize”.
3 Select the item to change the
settings of from the list.
Various setting can be changed.
Refer to the list of settings that can
be changed for details.
Customizable features
Your vehicle includes a vari-
ety of electronic features
that can be personalized to
your preferences. The set-
tings of these features can
be changed by using the
multi-information display,
the multimedia system or at
your Toyota dealer.
Vehicles with Toyota Team-
mate Advanced Drive, refer to
“Toyota Teammate Advanced
Drive OWNER’S MANUAL”.
Customizing vehicle fea-
tures
NOTICE
■During customization
To prevent 12-volt battery dis-
charge, ensure that the fuel cell
system is operating while custom-
izing features.

5269-3. Initialization
Owners Manual_USA_M62064_en
9-3.Initialization
Items to initialize
The following items must be initialized for normal system
operation after such cases as the 12-volt battery being recon-
nected, or maintenance being performed on the vehicle:
List of items to initialize
ItemWhen to initializeReference
Tire pressure warn-
ing system
• When the tire inflation pressure is changed, such as when
changing traveling speed or load
weight.
• When the tire inflation pressure is changed, such as when the
tire size is changed.
• When rotating the tires.
• After performing the transmitter
ID code registration procedure.
P.420