key battery TOYOTA MIRAI 2022 Owner's Guide

4738-2. Steps to take in an emergency
Owners Manual_USA_M62084_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.510)
●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.189)
■When replacing t he 12-volt bat-
tery
●Use a Central De gassing type 12-
volt battery (European Regula-
tions).

524What to do if... (Troubleshooting)
Owners Manual_USA_M62084_en
1-1.What to do if... (Troubleshooting)What to do if... (Troubleshooting)
 If you lose your mechanical
keys, new genuine mechani-
cal keys can be made by your
Toyota dealer. ( P.467)
 If you lose your electronic
keys, the risk of vehicle theft
increases significantly. Con-
tact your Toyota dealer imme-
diately. ( P.467)
 Is the electronic key battery
weak or depleted? ( P.423)
 Is the power switch in ON?
When locking the doors, turn the
power switch off. ( P.176)
 Is the electronic key left inside
the vehicle?
When locking the doors, make sure that you have the
electronic key on
your person.
 The function may not operate
properly due to the condition
of the radio wave. ( P.132)
 Is the child-protector lock set?
The rear door cannot be opened
from inside the vehicle when the
lock is set. Open the rear door from
outside and then unlock the child-
protector lock. ( P.124)
 The function to prevent the
electronic key from being left
inside the trunk will operate
and you can open the trunk as
usual. Take the key out from
the trunk. ( P.128)
 Did you press the power
switch while firmly depress-
ing the brake pedal?
( P.172)
 Is the electronic key any-
where detectable inside the
If you have a problem,
check the following before
contacting your Toyota
dealer.
The doors cannot be
locked, unlocked, opened
or closed
You lose your keys
The electronic key does
not operate properly
The doors cannot be
locked or unlocked
The rear door cannot be
opened
The trunk lid is closed
with the electronic key
left inside
If you think something is
wrong
The fuel cell system does
not start

Owners Manual_USA_M62084_en
525What to do if... (Troubleshooting)
vehicle? (P.130)
 Is the steering wheel
unlocked? ( P.173)
 Is the electronic key battery
weak or depleted?
In this case, the fuel cell system
can be started in a temporary way.
( P.470)
 Is the 12-volt battery dis-
charged? ( P.471)
 It is locked automatically to
prevent theft of the vehicle.
( P.173)
 Is the window lock switch
pressed?
The power window except for the
one at the driver’s seat cannot be
operated if the win dow lock switch
is pressed. ( P.158)
 The auto power off function
will be operated if the vehicle
is left in ACC for a period of
time. ( P.176) 
The seat belt reminder light is
flashing
Are the driver and the front passen-
ger wearing the seat belts?
( P.448)
 The parking brake indicator is
on
Is the parking br ake released?
(  P.183)
Depending on the situation,
other types of warning buzzer
may also sound. ( P.441, 451)
 Did anyone inside the vehicle
open a door during setting the
alarm?
The sensor detects it and the alarm
sounds. ( P. 7 0 )
Do one of the following to deac-
tivate or stop the alarms:
 Except for Canada: Unlock
the doors.
 Except for Canada: Unlock
the trunk using the mechani-
cal key.
 For Canada: Unlock the doors
or trunk using the entry func-
tion or wireless remote con-
trol.
The steering wheel can-
not be turned after the
fuel cell system is
stopped
The windows do not open
or close by operating the
power window switches
The power switch is
turned off automatically
A warning buzzer sounds
during driving
An alarm is a ctivated and
the horn sounds

528Alphabetical Index
Owners Manual_USA_M62084_en
Average vehicle speed........... 104
B
Back-up lights Replacing light bulbs ............ 429
Battery (12-volt battery) ......... 400 Battery checking................... 400
If the 12-volt battery is dis-charged .............................. 471
Preparing and c hecking before
winter.................................. 320
Warning light ........................ 442
Battery (traction battery) ......... 79
Blind Spot Monitor (BSM) ...... 249 Enabling/disabling the system........................................... 251
Brake Brake hold ............................ 186
Fluid ............................. 399, 486
Parking brake ....................... 183
Warning light ........................ 441
Brake assist ............................ 315
Break-in tips ........ ................... 162
Brightness control Instrument panel light control . 98
BSM (Blind Spot Monitor) ...... 249 Enabling/disabling the system........................................... 251
Buzzer Hands off steering wheel warn-ing (LTA) ............................. 232
Vehicle sway warning function (LTA) ................................... 233
C
Care ................................. 380, 384 Aluminum wheel ornaments . 380
Aluminum wheels ................. 380
Exterior ................................. 380
Interior .................................. 384
Roof film ............................... 381 Seat belts .............................384
Traction battery air intake vent
...........................................420
Cargo and luggage .................167
Cargo capacity ........................170
Chains......................................321
Child restraint system ..............52 Fixed with a LATCH system ...60
Fixed with a seat belt..............56
Front passenger occupant clas-sification system ...................46
Points to remember ................52
Riding with children ................51
Types of child restraint system installation method ...............54
Using an anchor bracket ........62
Child safety ...............................51 12-volt battery precautions .401, 474
Airbag precautions .................39
Child restraint system .............54
Electronic sunshade .............356
Heated steering wheel and seat heater precautio ns..............342
How your child should wear the seat belt ................................30
Power window lock switch ....158
Power window precautions...157
Rear door child-protectors ....124
Removed electronic key battery precautions .........................424
Seat belt extender precautions .............................................30
Seat belt precautions..............51
Trunk precautions .................126
Child-protectors......................124
Cleaning ..........................380, 384 Aluminum wheel ornaments .380
Aluminum wheels .................380
Exterior .................................380
Interior ..................................384
Radar sensor ........................208

530Alphabetical Index
Owners Manual_USA_M62084_en
Driving range ............................ 97
Driving support system informa- tion display ........................... 104
Dynamic radar cruise control with full-speed range ........... 237Approach warning ................ 244
Warning message ................ 247
E
ECB (Electronically Controlled Brake System) ...................... 315Warning light ........................ 441
ECO Accelerator Guidance ... 102
Eco score ................................ 102
EDR (Event data recorder)......... 8
Elapsed time ........................... 104
Electric motor (traction motor) ........................................... 74, 79Location.................................. 79
Specification ......................... 484
Electric Power Steering (EPS) ............................................... 315Warning light ........................ 443
Electronic key ......................... 118 Battery-saving function......... 131
If the electronic key does not operate properly ................. 468
Replacing the battery ........... 423
Electronic sunshade .............. 355 Operation ............................. 355
Electronically Controlled Brake System (ECB) ....................... 315Warning light ........................ 441
Emergency flashers ............... 432
Emergency shut off system .... 87
Emergency tire puncture ....... 455
Emergency tire puncture repair kitStorage location ................... 456
Emergency, in case of If a warning buzzer sounds .. 441
If a warning light turns on ..... 441 If a warning message is dis-
played .................................451
If the 12-volt battery is dis- charged ..............................471
If the electronic key does not operate properly .................468
If the fuel cell system will not start ....................................466
If the fuel door cannot be opened ...........................................468
If the vehicle is submerged or water on the road is rising ..433
If you have a flat tire .............455
If you lose your keys.............467
If you think something is wrong ...........................................439
If your vehicle becomes stuck ...........................................480
If your vehicle has to be stopped in an emergency .................432
If your vehicle needs to be towed ...........................................435
If your vehicle ove rheats ......476
Energy monitor ....................... 111
EPS (Electric Po wer Steering)
...............................................315 Warning light.........................443
Event data recorder (EDR) .........8
F
Flat tire.....................................455 Tire pressure w arning system
...........................................405
Floor mats .................................26
Fluid Brake ....................................486
Transmission ........................486
Washer .................................399
Footwell light ..........................346
Front footwell lights ...............346
Front passenger occupant clas- sification system ....................46

Owners Manual_USA_M62084_en
Alphabetical Index533
K
Keyless entrySmart key system................. 130
Wireless remote control ....... 119
Keys ......................................... 118 Battery-saving function......... 131
Electronic key ....................... 118
If the electronic key does not operate properly ................. 468
If you lose your keys ............ 467
Key number plate ................. 118
Keyless entry................ 121, 130
Mechanical key .................... 118
Power switch ........................ 172
Replacing the battery ........... 423
Warning buzzer .................... 130
Wireless remote control ....... 119
Knee airbags ............................. 34
L
Lane Tracing Assist (LTA)...... 223 Operation ............................. 223
Warning lights....................... 444
Warning messages............... 233
Language (multi-information dis- play) ....................................... 105
LATCH anchors ........................ 60
Lever Auxiliary catch lever ............. 393
Hood lock release lever........ 393
Internal trunk release lever... 128
Shift lever ............................. 177
Turn signal lever ................... 182
Wiper lever ........................... 197
License plate lights Light switch .......................... 191
Replacing light bulbs ............ 429
Light bulbs Replacing ............................. 429
Lights Automatic High Beam system ...........................................193
Front personal lights .............347
Headlight switch ...................191
Interior lights .................346, 347
Interior lights list ...................346
Rear personal lights .............347
Replacing light bulbs ............429
Trunk light .............................128
Turn signal lever ...................182
Vanity lights ..........................369
Lock steering column ............173
LTA (Lane Tracing Assist) ......223 Operation..............................223
Warning lights .......................444
Warning messages ...............233
Luggage mats .........................352
M
Maintenance Do-it-yourself maintenance ..391
General maintenance ...........388
Maintenance data .................482
Maintenance requirements ...387
Menu icons ..............................101
Meter Clock ......................................97
Driving range ..........................97
Indicators ................................94
Instrument panel light control .98
Meter control switches..........100
Meters ....................................97
Multi-information display.......100
Settings ................................105
Warning lights .................93, 441
Warning message.................451
Meter control switches...........100
Mirrors Digital Rearview Mirror .........144
Inside rear view mirror ..........143
Outside rear view mirror defog-gers ............................327, 334
Outside rear view mirrors .....154

536Alphabetical Index
Owners Manual_USA_M62084_en
Rear sunshades ..................... 370
Rear turn signal lights ........... 182 Replacing light bulbs ............ 429
Turn signal lever ................... 182
Rear view mirror Digital Rearview Mirror ......... 144
Inside rear view mirror.......... 143
Outside rear view mirrors ..... 154
Rear window defogger ... 327, 334
Refueling ................................. 203 Capacity ............................... 483
Fuel types............................. 483
When the fuel door cannot be opened ............................... 468
Regenerative braking ............... 76 Warning lights....................... 441
Replacing Electronic key battery ........... 423
Fuses ................................... 425
Light bulbs ............................ 429
Tires ..................................... 411
Road accident cautions ........... 86
Road Sign Assist .................... 234
Roof film .................................. 381
RSA (Road Sign Assist) ......... 234
Running out of fuel .................. 81
S
Safety Connect ......................... 65
Seat belt reminder light ......... 448
Seat belts .................................. 29 Automatic Locking Retractor .. 31
Child restraint system installation............................................. 54
Cleaning and maintaining the seat belt.............................. 384
Emergency Locking Retractor 31
How to wear your seat belt..... 30
How your child should wear the seat belt................................ 30
Pregnant women, proper seat belt use................................. 29 Reminder light and buzzer ...448
Seat belt extender ..................30
Seat belt pretensioners ..........32
SRS warning light .................442
Seat heaters ............................342
Seat position memory ............136
Seat ventilators .. .....................342
Seating capacity .............170, 482
Seats ........................................135 Adjustment ...........................135
Adjustment precautions ........135
Child seats/child restraint system installation ............................52
Cleaning ...............................384
Driving position memory .......136
Head restraints .....................139
Power easy access system ..136
Properly sitting in the seat ......27
Seat heaters ....... ..................342
Seat position memory...........136
Seat ventilators.....................342
Self-restoring coat ..................380
Sensor Automatic headlight system .192
Automatic High Beam system...........................................193
BSM (Blind Spot M onitor) .....250
Dynamic radar cruise control with full-speed range ..........207
Inside rear view mirror ..........144
Intuitive parking assist ..........254
LTA (Lane Tracing Assist) .....223
Parking Support Brake function (rear-crossing vehicles) ......250
Parking Support Brake function (static objects) ....................254
PCS (Pre-Collisio n System) .207
Radar sensor ........................207
Rain-sensing windshield wipers ...........................................199
RCTA (Rear Cross Traffic Alert) ...........................................250

Owners Manual_USA_M62084_en
Alphabetical Index539
Toyota multi-operation touch operation ............................ 354
Toyota Safety Sense 2.5 + ..... 207 AHB (Automatic High Beam) 193
Dynamic radar cruise control with full-speed range .......... 237
LTA (Lane Tracing Assist) ..... 223
PCS (Pre-Collision System) . 212
RSA (Road Sign Assist) ....... 234
Toyota Teammate Advanced Park ....................................... 284Memory function................... 297
Parallel parking departure func- tion ..................................... 295
Parallel parking function ....... 292
Perpendicular parking function ........................................... 290
Sensors ................................ 309
Settings ................................ 311
Warning message ................ 302
TRAC (Traction Control) ........ 315
Traction battery ........................ 79 Charging................................. 76
Location.................................. 79
Specification ......................... 484
Traction battery air intake vents............................................. 88
Traction battery air intake vent ............................................... 420
Traction battery air intake vents ................................................. 88
Traction Control (TRAC) ........ 315
Traction motor (electric motor)74
Trailer towing .......................... 171
Trip meters ................................ 98
Trunk ....................................... 126 Internal trunk release lever... 128
Smart key system................. 127
Trunk easy closer ................. 128
Trunk features ...................... 352
Trunk grip ............................. 128
Trunk light............................. 128 Trunk opener main switch ....129
Trunk opener switch .............127
Wireless remote control........127
Trunk light ...............................128
Turn signal lights ....................182 Replacing light bulbs ............429
Turn signal lever ...................182
U
USB charging ports ................356
V
Vanity lights ............................369
Vanity mirrors .........................369
VDIM (Vehicle Dynamics Inte-grated Management) ............315
Vehicle data recording ...............7
Vehicle Dynamics Integrated Management (VDIM ) .............315
Vehicle identification number482
Vehicle information display ...104
Vehicle Stability Control (VSC) ...............................................315
Ventilators (seat ventilators) .342
VSC (Vehicle Stability Control) ...............................................315
W
Warning buzzers Approach warning ................244
Brake hold ............................446
Brake Override System ........446
Brake system ........................441
Drive-Start Control ................446
Electric power steering .........443
Fuel cell system overheat .....442
Hands off steering wheel warn- ing (LTA) .............................232
High coolant temperature .....442
Hydrogen leak ......................441