2020 TOYOTA MIRAI change key battery

1404-2. Opening, closing and locking the doors
MIRAI_OM_USA_OM62073U
■Tr u n k l i g h t
The trunk light turns on when the trunk is opened.
■ Function to prevent th e trunk being locked with the electronic key inside
● When all doors are locked, closing the trunk lid with the elect ronic key left
inside the trunk will sound an alarm.
In this case, the trunk lid can be opened by pressing the trunk release but-
ton on the trunk lid.
● If the spare electronic key is put in the trunk with all the doors locked, the
key confinement prevention function is activated so the trunk can be
opened. In order to prevent theft, take all electronic keys wit h you when
leaving the vehicle.
● If the electronic key is put in the trunk with all the doors lo cked, the key may
not be detected depending on the location of the key and the su rrounding
radio wave conditions. In this case, the key confinement preven tion function
cannot be activated, causing the doors to lock when the trunk i s closed.
Make sure to check where the key is before closing the trunk.
● The key confinement prevention function cannot be activated if any one of
the doors is unlocked. In this case, open the trunk using the t runk opener
switch.
■ Internal trunk release lever
■ Using the mechanical key
The trunk can be also opened using the mechanical key. ( P. 449)
■ Open trunk warning buzzer
If the vehicle speed reaches 3 mph (5 km/h), the master warning light flashes
and a buzzer sounds to indicate that the trunk is not fully clo sed.
■ If the smart key system or the wireless remote control does not operate
properly
Use the mechanical key to unlock the trunk. ( P. 449)
Replace the key battery with a new one if it is depleted. ( P. 400)
■ When leaving a key to the vehicle with a parking attendant
P. 129
■ Customization
The trunk unlocking operation can be changed.
(Customizable features: P. 487)
The trunk lid can be opened by pulling the
glow-in-the-dark lever located on the
inside of the trunk lid upward.
The lever will continue to glow for some
time after the trunk lid is closed.

1474-2. Opening, closing and locking the doors
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Operation of each component
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Note for the entry function
●Even when the electronic key is within the effective range (det ection areas),
the system may not operate properly in the following cases:
• The electronic key is too close to the window or outside door handle, near
the ground, or in a high place when the doors are locked or unl ocked.
• The electronic key is near the ground or in a high place, or t oo close to
the rear bumper center when the trunk is opened.
• The electronic key is on the instrument panel, rear package tr ay or floor,
or in the door pockets or glove box when the fuel cell system i s started or
power switch modes are changed.
● Do not leave the electronic key on top of the instrument panel or near the
door pockets when exiting the vehicle. Depending on the radio w ave recep-
tion conditions, it may be detected by the antenna outside the cabin and the
door will become lockable from the outside, possibly trapping the electronic
key inside the vehicle.
● As long as the electronic key is within the effective range, th e doors may be
locked or unlocked by anyone. However, only the doors detecting the elec-
tronic key can be used to unlock the vehicle.
● Even if the electronic key is not inside the vehicle, it may be possible to start
the fuel cell system if the electronic key is near the window.
● The doors may unlock or lock if a large amount of water splashe s on the
door handle, such as in the rain or in a car wash when the elec tronic key is
within the effective range. (The doors will automatically be lo cked after
approximately 60 seconds if the doors are not opened and closed.)
● If the wireless remote control is used to lock the doors when t he electronic
key is near the vehicle, there is a possibility that the door m ay not be
unlocked by the entry function. (Use the wireless remote contro l to unlock
the doors.)
● Touching the door lock or unlock sensor while wearing gloves ma y prevent
lock or unlock operation.
● When the lock operation is performed using the lock sensor, rec ognition sig-
nals will be shown up to two consecutive times. After this, no recognition
signals will be given.
● If the door handle becomes wet while the electronic key is with in the effec-
tive range, the door may lock and unlock repeatedly. In this ca se, follow the
following correction procedures to wash the vehicle:
• Place the electronic key in a location 6 ft. (2 m) or more awa y from the
vehicle. (Take care to ensure that the key is not stolen.)
• Set the electronic key to battery-saving mode to disable the s mart key
system. ( P. 145)
● If the electronic key is inside the vehicle and a door handle b ecomes wet
during a car wash, a message may be shown on the multi-informat ion dis-
play and a buzzer will sound outside the vehicle. To turn off t he alarm, lock
all the doors.

1885-2. Driving procedures
MIRAI_OM_USA_OM62073U
Modes can be changed by pressing the power switch with brake pedal
released. (The mode changes each time the switch is pressed.)
Off
The emergency flashers can be
used.
ACCESSORY mode
Some electrical components such
as the audio system can be used.
“Accessory” will be displayed on
the main display.
ON mode
All electrical components can be
used.
“Ignition On” will be displayed on
the main display.
■ Auto power off function
If the vehicle is left in ACCESSORY mode for more than 20 minut es or ON
mode (the fuel cell system is not operating) for more than an h our with the
shift position in P, the power switch will automatically turn o ff. However, this
function cannot entirely prevent 12-volt battery discharge. Do not leave the
vehicle with the power switch in ACCESSORY or ON mode for long periods
of time when the fuel cell system is not operating.
■ Sounds and vibrations speci fic to a fuel cell vehicle
P. 88
■ Electronic key battery depletion
P. 130
Changing power switch modes

1915-2. Driving procedures
5
Driving
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If “Smart Key System Malfunction See Owner’s Manual” is displayed on
the multi-information display
The system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer immediately.
■ If the “READY” indicator does not come on
In the event that the “READY” indicator does not come on even a fter perform-
ing the proper procedures for starting the vehicle, contact you r Toyota dealer
immediately.
■ If the fuel cell system is malfunctioning
P. 426
■ If the electronic key battery is depleted
P. 400
■ Operation of the power switch
If the switch is not pressed shortly and firmly, the power swit ch mode may not
change or the fuel cell system may not start.
■ Automatic P position selection function
●When the shift position is other than P, pressing the power swi tch with the
vehicle stopped completely will cause the shift position to cha nge to P auto-
matically, and then the power switch will turn off.
● When turning the power switch off with the shift position other than P, firmly
depress the brake pedal and confirm that the shift position* ha s changed to
P before slowly releasing the brake pedal.
*: Even after the instrument panel display has been turned off, t he shift
position indicator will continue to be displayed for several se conds.
■ If the shift control system malfunctions
The power switch will not be able to be turned off. In this occurs, the switch
can be turned off by applying the parking brake.
If the system malfunctions, have your vehicle serviced by your Toyota dealer
immediately.
■ If the smart key system has been d eactivated in a customized setting
P. 486

2045-3. Operating the lights and wipers
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Automatic light off system
●When the headlights are on: The headlights and tail lights turn off 30 sec-
onds after a door is opened and closed if the power switch is t urned to
ACCESSORY mode or turned off. (The lights turn off immediately if
on the key is pressed after all the doors are locked.)
● When only the tail lights are on: The tail lights turn off automatically if the
power switch is turned to ACCESSORY mode or turned off and the driver’s
door is opened.
To turn the lights on again, turn the power switch to ON mode, or turn the light
switch or once and then back to or .
If any of the doors or trunk lid is kept open, the lights automatically turn off
after 20 minutes.
■ Automatic headlight leveling system
The level of the headlights is automatically adjusted according to the number
of passengers and the loading condition of the vehicle to ensur e that the
headlights do not interfere with other road users.
■ Light reminder buzzer
A buzzer sounds when the power switch is turned off or turned t o ACCES-
SORY mode and the driver’s door is opened while the lights are turned on.
■ 12-volt battery-saving function
In order to prevent the 12-volt battery of the vehicle from dis charging, if the
headlights and/or tail lights are on when the power switch is t urned off the
12-volt battery saving function will operate and automatically turn off all the
lights after approximately 20 minutes. When the power switch is turned to ON
mode, the 12-volt battery-saving function will be disabled.
When any of the following are performed, the 12-volt battery-sa ving function
is canceled once and then reactivated. All the lights will turn off automatically
20 minutes after the 12-volt battery-saving function has been r eactivated:
● When the headlight switch is operated
● When a door is opened or closed
■ Customization
Settings (e.g. light sensor sensitivity) can be changed.
(Customizable features: P. 488)
NOTICE
■To prevent 12-volt b attery discharge
Do not leave the lights on longer than necessary when the fuel cell system
is off.

4318-2. Steps to take in an emergency
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When trouble arises
■If “Shifted to [N] Position To Shift to [P], Stop Your Vehicle and Press [P]
Switch” is displayed
When the vehicle is moving, a warning message is displayed when the P
position switch is operated and attempting to shift the shift p osition to P.
The shift position is changed to N.
Operate the P position switch after the vehicle has been brough t to a com-
plete stop.
■ If “Smart Key System Malfunction See Owner’s Manual” is displayed
P. 145
■ If “Front Camera Unavailable” or “Front Camera Unavailable See
Owner’s Manual” is displayed
The following systems may be suspended until the problem shown in the
message is resolved. ( P. 224)
● PCS (Pre-Collision System)
● LDA (Lane Departure Alert with steering control)
● Automatic High Beam
● RSA (Road Sign Assist) (if equipped)
● Dynamic radar cruise control
■ If “Radar Cruise Control Unavailable See Owner's Manual” is sho wn
The dynamic radar cruise control system is suspended temporaril y or until the
problem shown in the message is resolved. (causes and coping me thods:
P. 224)
■ If “Radar Cruise Control Unavailable” is shown
The dynamic radar cruise control system cannot be used temporar ily. Use the
system when it becomes available again.
■ If the shift position cannot be changed or the power switch is turned to
ACCESSORY mode even if trying to turn the power switch off when a
warning message is shown
If the 12-volt battery is discharged or the shift control syste m is malfunction-
ing, the followings may occur.
● The shift position may not be changed to P.
When parking, stop the vehicle on level ground and apply the pa rking brake
firmly.
● The fuel cell system may not start.
● The power switch may be turned to ACCESSORY mode even if trying to
turn the power switch off.
In this case, the power switch may be turned off after applying the parking
brake.
● The automatic P position selection function ( P. 191) may not operate.
Before turning the power switch off, be sure to press the P pos ition switch
and check that the shift position is in P by the shift position indicator or P
position switch indicator.
■ Warning buzzer
P. 424

4518-2. Steps to take in an emergency
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When trouble arises
■Stopping the fuel cell system
Shift the shift position to P and press the power switch as you normally do
when stopping the fuel cell system.
■ Replacing the key battery
As the above procedure is a temporary measure, it is recommende d that the
electronic key battery be replaced immediately when the battery is depleted.
( P. 400)
■ Alarm
Using the mechanical key to lock the doors will not set the ala rm system.
If a door is unlocked using the mechanical key when the alarm system is set,
the alarm may be triggered. ( P. 82)
■ When the electronic key does not work properly
●Make sure that the smart key system has not been deactivated in the cus-
tomization setting. If it is off, turn the function on.
(Customizable features P. 486)
● Check if battery-saving mode is set. If it is set, cancel the f unction.
( P. 145)
■ Changing power switch modes
Release the brake pedal and press the power switch in step abo ve.
The fuel cell system does not start and modes will be changed each time the
switch is pressed. ( P. 188)
WARNING
■When using the mechanical key and operating the power windows
Operate the power window after checking to make sure that there is no pos-
sibility of any passenger having any of their body parts caught in the win-
dow.
Also, do not allow children to operate the mechanical key. It is possible for
children and other passengers to get caught in the power window .
3

4939-2. Customization
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Vehicle specifications
■Vehicle customization
●When the speed linked door locking function and shift position linked door
locking function are both on, the door lock operates as follows .
• When shifting the shift position to any position other than P, all the doors
will be locked.
• If the vehicle is started with all the doors locked, the speed linked door locking function would not operate.
• If the vehicle is started with any door unlocked, the speed li nked door
locking function will operate.
● When the smart key system is off, smart door unlocking cannot be custom-
ized.
● When the doors remain closed after unlocking the doors and the automatic
door lock function is activated, the signals will be generated in accordance
with the operation signal (buzzer) and the operation signal (em ergency
flashers) settings.
■ In the following situations, customize mode in which the settin gs can be
changed through the multi-information display will automaticall y be
turned off.
● A warning message appears after the customize mode screen is di splayed.
● The vehicle begins to move while the customize mode screen is d isplayed.
NOTICE
■During customization
To prevent 12-volt battery discharge, ensure that the fuel cell system is
operating while customizing features.