2021 TOYOTA SIENNA HYBRID key battery

5047-2. Steps to take in an emergency
■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.
(Customizable features: P.544)
●Check if battery-saving mode is
set. If it is set, cancel the function.
( P.166)
Use the mechanical key
( P.131) in order to perform the following operations.
1
Locks all the doors
2 Unlocks the door
■Key linked functions
The opening and closing of the
power windows and moon roof can
be linked to key operation by a cus-
tomized setting at your Toyota
dealer.
1 Closes the windows and the
moon roof
* (turn and hold)
2 Opens the windows and the
moon roof
* (turn and hold)
*: If equipped
If the electronic key
does not op erate prop-
erly
If communication between
the electronic key and vehi-
cle is interrupted ( P.166)
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 can
be opened and the hybrid
system can be started by
following the procedure
below.
NOTICE
■In case of a smart key system
malfunction, or other key
related problems
Take your vehicle with all the
electronic keys provided with your
vehicle to your Toyota dealer.
Locking and unlocking
the doors

5057-2. Steps to take in an emergency
7
When trouble arises
1Ensure that the shift lever is
in P and depress the brake
pedal.
2 Touch the electronic key to
the power switch as shown in
the illustration.
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 displayed on the multi-infor-
mation display.
4 Press the power switch
shortly and firmly.
In the event that t he hybrid system
still cannot be started, contact your
Toyota dealer.
■Stopping the hybrid system
Shift the shift lever to P, set the
parking brake and press the power
switch as you normally do when
stopping the hybrid system.
■Replacing the key battery
As the above proce dure is a tempo-
rary measure, it is recommended
that the electronic key battery be
replaced immediately when the bat-
tery is depleted. ( P.447)
■Changing power switch modes
Release the brake pedal and press
the power switch in step 3 above.
The hybrid system does not start
and modes will be changed each
time the switch is pressed.
(  P.234)
WARNING
■When using the mechanical
key and operating the power
windows or the moon roof (if
equipped)
Operate the power window or the
moon roof after checking to make
sure that there is n o possibility of
any passenger having any of their
body parts caught in the window
or the moon roof. 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 or
the moon roof.
Starting the hybrid sys-
tem

5067-2. Steps to take in an emergency
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.
1Vehicles with alarm: 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 the doors locked. (
P.90)
2 Open the hood ( P.413) and
fuse box cover.
Push claw , and to com-
pletely release the lock, and then lift
up the cover.
3 Open the exclusive jump
starting terminal cover.
4 Connect a positive jumper cable 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
If the 12-volt battery is
discharged
The following procedures
may be used to start the
hybrid system if the vehi-
cle’s 12-volt battery is dis-
charged.
You can also call your
Toyota dealer or a qualified
repair shop.
Restarting the hybrid sys-
tem
ABC
A
B
C

5087-2. Steps to take in an emergency
possible.
■Starting the hybrid system
when the 12-volt battery is dis-
charged
The hybrid system cannot be
started by push-starting.
■To prevent 12-vol t battery dis-
charge
●Turn off the headlights and the
audio system while the hybrid sys-
tem is off.
●Turn off any unnec essary 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 your Toyota dealer.
●Some systems may require initial-
ization. ( P.554)
■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 certa in electrical appli-
ances. If the vehicle is left for a long
time, the 12-volt battery may dis-
charge, and the hybrid system may
be unable to start. (The 12-volt bat-
tery recharges aut omatically while
the hybrid system is operating.)
■When recharging or replacing
the 12-volt battery
●In some cases, i t 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 hybrid syste m may not start
on the first attemp t after reinstall-
ing the 12-volt battery. In that
case, start the hybrid system in
the same manner as when the
electronic key does not operate
properly ( P.505). This is not a
malfunction, as the hybrid system
will start normally on the second
attempt.
●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 replacing t he 12-volt bat-
tery
●Use a 12-volt battery that con-
forms to European regulations.
Use a battery that the case size is
same as the previous one (LN2),
20 hours rate ca pacity (20HR) is
equivalent (60Ah) or greater, and
performance rating (CCA) is
equivalent (563A) 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 p eriod where the
vehicle is not used is a short time,
the 12-volt battery may discharge
and hybrid system may not be
able to start.
●Use a 12-volt battery with a han-
dle. If a 12-volt battery without a
handle is used, removal is more
difficult.
●When removing the 12-volt bat-

568What to do if... (Troubleshooting)
1-1.What to do if... (Troubleshooting)What to do if... (Troubleshooting)
If you lose your keys or
mechanical keys, new genu-
ine keys or mechanical keys
can be made by your Toyota
dealer. ( P.502)
 If you lose your electronic
keys, the risk of vehicle theft
increases significantly. Con-
tact your Toyota dealer imme-
diately. ( P.502)
 Is the key battery weak or
depleted? ( P.447)
 Vehicles with entry function:
Is the power switch in ON?
When locking the doors, turn
the power switch off.
( P.234)
 Vehicles with entry function:
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.166)
 Is the child-protector lock set?
The sliding door cannot be
opened from inside the vehi-
cle when the lock is set. Open
the sliding door from outside
and then unlock the child-pro-
tector lock. ( P.142)
 Did you press the power
switch while firmly depress-
ing the brake pedal?
( P.231)
 Is the shift lever in P?
( P.231)
 Is the electronic key any-
where detectable inside the
vehicle? ( P.165)
 Is the steering wheel
unlocked? ( P.232)
 Is the electronic key battery
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 doors cannot be
locked or unlocked
The sliding door cannot
be opened
If you think something is
wrong
The hybrid system does
not start

572Alphabetical Index
........................................... 155
Power back door .................. 153
Wireless remote control ....... 153
Back-up lights Replacing light bulbs ............ 451
Wattage ................................ 526
Battery (12-volt battery) ......... 422 If the 12-volt battery is dis-charged .............................. 506
Preparing and c hecking before
winter.................................. 343
Replacing ............................. 508
Warning light ........................ 466
Battery (traction battery) ......... 83
Blind Spot Monitor (BSM) ...... 299 Blind Spot Monitor function .. 302
Rear Cross Traffic Alert function........................................... 305
Bottle holders ......................... 369
Brake Brake Hold ........................... 246
Fluid ............................. 420, 524
Parking brake ....................... 243
Regenerative braking ............. 80
Warning light ........................ 466
Brake assist ............................ 335
Brake Hold .............................. 246
Break-in tips ........ ................... 209
Brightness control Instrument panel light control .......................... 99, 103
BSM (Blind Spot Monitor) ...... 299 Blind Spot Monitor function .. 302
Rear Cross Traffic Alert function........................................... 305
C
Care Aluminum wheels ................. 400
Exterior ................................. 400
Interior .................................. 403
Seat belts ............................. 403 Cargo capacity ................215, 218
Cargo hooks............................372
Chains......................................345
Child-protectors......................142
Child restraint system ..............58
Fixed with a LATCH system ...68
Fixed with a seat belt..............63
Front passenger occupant clas-sification system ...................51
Points to remember ................58
Riding with children ................57
Types of child restraint system installation method ...............60
Using an anchor bracket ........71
Child safety ...............................57 12-volt battery precautions .................422, 509
Airbag precautions .................46
Back door precautions..........150
Child restraint system .............60
Heated steering wheel and seat heater precautio ns..............361
How your child should wear the seat belt ................................36
Moon roof precautions..........205
Power window lock switch ....203
Power window precautions...202
Removed key battery precau- tions ....................................448
Seat belt extender precautions .............................................36
Seat belt precautions..............35
Seat heater precautions .......361
Cleaning ..........................400, 403 Aluminum wheels .................400
Exterior .................................400
Hybrid battery (tr action battery)
air intake vents and filters...443
Interior ..................................403
Radar sensor ........................263
Seat belts .............................403
Clock ................................100, 104

574Alphabetical Index
tion display ........................... 110
Dynamic radar cruise control with full-speed rangeFunction ............................... 288
Warning message ................ 477
E
ECB (Electronically Controlled Brake System) ...................... 335
Eco drive mode ...................... 333
EDR (Event data recorder)......... 8
E-Four (Electronic On-Demand AWD system) ........................ 336
Elapsed time ........................... 111
Electric motor Location.................................. 79
Specification ......................... 520
Electric Power Steering (EPS) Function ............................... 336
Warning light ........................ 468
Electronically Controlled Brake System (ECB) ....................... 335
Electronic key Battery-saving function......... 165
If the electronic key does not operate properly ................. 504
Replacing the battery ........... 447
Emergency, in case of If a warning buzzer sounds .. 466
If a warning light turns on ..... 466
If a warning message is dis-played................................. 477
If the 12-volt battery is dis- charged .............................. 506
If the electronic key does not operate properly ................. 504
If the fuel filler door cannot be opened ............................... 503
If the hybrid sy stem will not start
........................................... 501
If the vehicle is trapped in rising water .................................. 460 If you have a flat tire .....481, 491
If you lose your keys.............502
If you think something is wrong
...........................................465
If your vehicle becomes stuck ...........................................514
If your vehicle has to be stopped in an emergency .................459
If your vehicle needs to be towed ...........................................462
If your vehicle ove rheats ......511
Emergency flashers ...............458
Energy monitor .......................122
Engine Compartment........................416
Hood .....................................413
Identification number ............520
Engine coolant Capacity ...............................522
Checking ..............................419
Preparing and checking before winter ..................................343
Warning light ........................467
Engine coolant temperature gauge ...............................97, 101
Engine oil Capacity ...............................521
Checking ..............................416
Preparing and checking before winter ..................................343
Warning light ........................467
Engine oil maintenance data .418
Enhanced Vehicle Stability Con- trol (Enhanced VSC ) .............335
Enhanced VSC (Enhanced Vehi- cle Stability Control).............335
EPS (Electric Po wer Steering)
Function................................336
Warning light ........................468
EV drive mode.........................236
Event data recorder (EDR) .........8
EV indicator...............................80

Alphabetical Index577
Intuitive parking assistFunction ............................... 308
Warning message ................ 311
J
JackPositioning a floor jack ......... 415
Vehicle-equipped jack .. 483, 492
Jack handle ..................... 483, 492
Jam protection function Moon roof ............................. 204
Power back door .................. 157
Power windows .................... 201
Sliding doors ........................ 143
K
Keyless entrySmart key system................. 164
Wireless remote control ....... 130
Keys ......................................... 128 Battery-saving function......... 165
Electronic key ....................... 128
If the electronic key does not operate properly ................. 504
If you lose your keys ............ 502
Key number plate ................. 128
Keyless entry................ 130, 164
Mechanical key .................... 131
Power switch ........................ 231
Replacing the battery ........... 447
Warning buzzer .................... 165
Wireless remote control key . 130
Knee airbags ............................. 41
L
Lane Tracing Assist (LTA) ..... 275 Operation ............................. 275
Warning messages .............. 285
Language (multi-information dis- play) ............................... 115, 541 LATCH anchors ........................68
Lever
Auxiliary catch lever .............413
Hood lock release lever ........413
Shift lever .............................238
Turn signal lever . ..................242
Wiper lever ...................254, 257
License plate lights Light switch...........................248
Replacing light bulbs ............451
Wattage ................................526
Light bulbs Replacing .............................451
Wattage ................................526
Lights Automatic High Beam system...........................................250
Fog light switch .....................254
Headlight switch ...................248
Interior lights .........................364
Personal lights ......................364
Rear interior light ..................364
Replacing light bulbs ............451
Turn signal lever . ..................242
Vanity lights ..........................374
Wattage ................................526
Lock steering column ............232
LTA (Lane Tracing Assist) .....275 Operation..............................275
Warning messages ...............285
Luggage compartment light ................................152, 156Wattage ................................526
M
Maintenance Do-it-yourself maintenance ..411
General maintenance ...........407
Maintenance data .................518
Maintenance requirements ...406
Malfunction indicator lamp ....467
Menu icons ..............................106