2021 TOYOTA SIENNA HYBRID Owners Manual (in English)

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

5077-2. Steps to take in an emergency
7
When trouble arises
on the second vehicle and connect the clamp at the other end of
the negative cable to .
Exclusive jump starting terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery term inal (second vehicle)
Solid, stationary, unpainted metallic point away from the exclu -
sive jump starting terminal and any moving parts as shown in th e
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 hybrid system of your
vehicle by turning the power
switch to ON. 8
Make sure the “READY” indi-
cator comes on. If the indica-
tor light does not come on,
contact your Toyota dealer.
9 Once the hybrid 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
reinstall the fuse box cover to
its original position.
Once the hybrid system starts,
have the vehicle inspected at
your Toyota dealer as soon as
D
A
B
C
D

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-

5097-2. Steps to take in an emergency
7
When trouble arises
tery: P.423
●After exchanging, 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 exchangi ng and confirm
that it is firmly connected to the
hole section of the vehicle.
• Use the exhaust hole plug included with the 12-volt battery
exchanged or the one installed on
the battery prior to the exchange.
(Depending on the 12-volt battery
to be exchanged, the exhaust hole
may be plugged.)
For details, consult your Toyota
dealer.
Exhaust hole
Exhaust hose
Hole section of the vehicle
WARNING
■When removing the 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, l eading to a fire
in addition to electrical shocks
and death or serious injury.
C
BA
A
B
C
■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:
●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.

5107-2. Steps to take in an emergency
WARNING
●Always wash your hands after
handling the 12-volt battery sup-
port, terminals, and other bat-
tery-related parts.
●Do not allow children 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
●For information regarding 12-
volt battery replacement, con-
tact your To yota dealer.
●After exchanging, securely
attach the exhaust hose and
exhaust hole plug to the
exhaust hole of the exchanged
12-volt battery. If not properly
installed, gases (hydrogen) may
leak into the vehicle interior, and
there is the possible danger of
the gas igniting and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan, etc.
■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.

5117-2. Steps to take in an emergency
7
When trouble arises
■If the engine coolant tem-
perature gauge enters the
red zone or “Engine Cool-
ant Temp High Stop in a
Safe Place See Owner’s
Manual” is shown on the
multi-information display
1 Stop the vehicle in a safe
place and turn off the air con-
ditioning system, and then
stop the hybrid system. 2
If you see steam:
Carefully lift the hood after
the steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the hybrid system has
cooled down sufficiently,
inspect the hoses and radia-
tor core (radiator) for any
leaks.
Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
4The coolant level is satisfac-
tory if it is between the
“FULL” and “LOW” lines on
the reservoir.
Reservoir
“FULL” line
If your vehicle over-
heats
The following may indicate
that your vehicle is over-
heating.
The needle of the engine
coolant temperature gauge
( P.97, 101) enters the red
zone, or a loss of hybrid
system power is experi-
enced. (For example, the
vehicle speed does not
increase.)
 “Engine Coolant Temp High
Stop in a Safe Place See
Owner’s Manual” or “Hybrid
System Overheated Output
Power Reduced” is shown
on the multi-information dis-
play.
 Steam comes out from
under the hood.
Correction procedures
A
B
A
B