2023 TOYOTA SIENNA HYBRID horn

1873-4. Adjusting the steering wheel and mirrors
3
Before driving
To sound the horn, press on or
close to the mark.
*: If equipped
The height of the rear view mir-
ror can be adjusted to suit your
driving posture.
Adjust the height of the rear
view mirror by moving it up and
down.
WARNING
■Caution while driving
Do not adjust the steering wheel
while driving.
Doing so may cause the driver to
mishandle the vehicle and cause
an accident, resul ting in death or
serious injury.
■After adjusting the steering
wheel (manual type)
Make sure that the steering wheel
is securely locked.
Otherwise, the steering wheel
may move suddenly, possibly
causing an accident, and resulting
in death or serious injury. Also,
the horn may not sound if the
steering wheel is not securely
locked.
Sounding the horn
Inside rear view mir-
ror*
The rear view mirror’s posi-
tion can be adjusted to
enable sufficient confirma-
tion of the rear view.
Adjusting the height of
rear view mirror
WARNING
■Caution while driving
Do not adjust the position of the
mirror while driving.
Doing so may lead to mishandling
of the vehicle and cause an acci-
dent, resulting in death or serious
injury.

3154-5. Using the driving support systems
4
Driving
Also, due to ice forming on a sensor
at low temperatures, a warning
message may be displayed or the
sensor may not be able to detect an
object. Once the ice melts, the sys-
tem will return to normal.
If a warning message is displayed
even if the sensor is clean, there
may be a sensor malfunction. Have
the vehicle insp ected by your
Toyota dealer.
■If “Parking Assi st Unavailable”
is displayed on the multi-infor-
mation display
Water may be con tinuously flowing
over the sensor surface, such as in
a heavy rain. When the system
determines that it is normal, the sys-
tem will return to normal.
■Sensor detection information
●The sensor’s detection areas are
limited to the areas around the
vehicle’s front and rear bumpers.
●The following situations may occur
during use.
• Depending on the shape of the object and other factors, the
detection distance may shorten,
or detection may be impossible.
• Detection may be impossible if static objects draw too close to the
sensor.
• There will be a short delay
between static object detection
and display (warning buzzer
sounds). Even at low speeds,
there is a possibilit y that the object
will come within approximately
11.9 in. (30 cm) before the display
is shown and the warning buzzer
sounds.
• It might be difficult to hear the buzzer due to the volume of the
audio system or air flow noise of
the air conditioning system.
• It may be difficult to hear the sound of this system due to the
buzzers of other systems.
■Objects which the system may
not properly detect
The shape of the object may pre-
vent the sensor from detecting it.
Pay particular atte ntion to the fol-
lowing objects:
●Wires, fences, ropes, etc.
●Cotton, snow and other materials
that absorb sound waves
●Sharply-angled objects
●Low objects
●Tall objects with upper sections
projecting outwards in the direc-
tion of your vehicle
People may not be detected if they
are wearing certain types of cloth-
ing.
■Situations in which the system
may not operate properly
Certain vehicle conditions and the
surrounding environment may affect
the ability of a sensor to correctly
detect objects. Part icular instances
where this may occur are listed
below.
●There is dirt, snow or ice on a sen-
sor. (Cleaning th e sensors will
resolve this problem.)
●A sensor is froz en. (Thawing the
area will resolve this problem.)
In especially cold weather, if a sen-
sor is frozen the s ensor display may
be displayed abnormally, or objects,
such as a wall, may not be detected.
●When a sensor or the area around
a sensor is extremely hot or cold.
●On an extremely bumpy road, on
an incline, on gravel, or on grass.
●When vehicle horns, vehicle

3174-5. Using the driving support systems
4
Driving
●When vehicle horns, vehicle
detectors, motorcycle engines, air
brakes of large vehicles, the clear-
ance sonar of other vehicles or
other devices which produce ultra-
sonic waves are near the vehicle.
●If the front of the vehicle is raised
or lowered due to the carried load.
●If the orientation of a sensor has
been changed due to a collision or
other impact.
●The vehicle is approaching a tall
or curved curb.
●Driving close to columns (H-
shaped steel beams, etc.) in multi-
story parking garages, construc-
tion sites, etc.
●If the vehicle cannot be driven in a
stable manner, such as when the
vehicle has been in an accident or
is malfunctioning.
●On an extremely bumpy road, on
an incline, on gravel, or on grass.
●When tire chains, a compact
spare tire or an emergency tire
puncture repair kit are used.
■Detection range of the sen-
sors
Approximately 3.3 ft. (100
cm)
Approximately 4.9 ft. (150
cm)
Approximately 2.0 ft. (60 cm)
The diagram shows the detection
range of the sensors. Note that the
sensors cannot detect objects that
are extremely clos e to the vehicle.
The range of the sensors may
change depending on the shape of
the object, etc.
■Distance display
When an object is detected by a
sensor, the approximate dis-
tance to the object will be dis-
played on the multi-information
display and audio system
screen. (As the distance to the
object becomes short, the dis-
tance segments may blink.)
Sensor detection display,
object distance
A
B
C

4997-2. Steps to take in an emergency
7
When trouble arises
One of the following may be the
cause of the problem:
The electronic key may not be
functioning properly.
( P.502)
 There may not be sufficient
fuel in the vehicle’s tank.
Refuel the vehicle. ( P.262)
 There may be a malfunction
in the immobilizer system.
( P.88)
 The hybrid system may be
malfunctioning due to an elec-
trical problem such as elec-
tronic key battery depletion or
a blown fuse. However,
depending on the type of mal-
function, an interim measure
is available to start the hybrid
system. ( P.499) One of the following may be the
cause of the problem:

The 12-volt battery may be
discharged. ( P.504)
 The 12-volt battery terminal
connections may be loose or
corroded. ( P.420)
One of the following may be the
cause of the problem:
 The 12-volt battery may be
discharged. ( P.504)
 One or both of the 12-volt bat-
tery terminals may be discon-
nected. ( P.420)
Contact your Toyota dealer if
the problem cannot be repaired,
or if repair procedures are
unknown.
When the hybrid system does
not start, the following steps can
be used as an interim measure
to start the hybrid system if the
power switch is functioning nor-
If the hybrid system
will not start
Reasons for the hybrid sys-
tem not starting vary
depending on the situation.
Check the following and
perform the appropriate
procedure:
The hybrid system will not
start even though the cor-
rect starting procedure is
being followed ( P.234)
The interior lights and
headlights are dim, or the
horn does not sound or
sounds at a low volume
The interior lights and
headlights do not turn on,
or the horn does not
sound
Starting the hybrid sys-
tem in an emergency

567What to do if... (Troubleshooting)
porary way. (P.503)
 Is the 12-volt battery dis-
charged? ( P.504)
 Is the power switch in ON?
If you cannot release the shift
lever by depressing the brake
pedal with the power switch in
ON ( P.243)
 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.204)
 The auto power off function
will be operated if the vehicle
is left in ACC or ON (the
hybrid system is not operat-
ing) for a period of time.
( P.238)
 The seat belt reminder light is
flashingAre the driver and the passengers
wearing the seat belts? ( 
P.471)
The parking brake indicator is
on
Is the parking br ake released?
( 
P.246)
Depending on the situation,
other types of warning buzzer
may also sound. ( P.464, 475)
 Did anyone inside the vehicle
open a door during setting the
alarm?
The sensor detects it and the
alarm sounds. ( P.89)
To stop the alarm, turn the power
switch to ON or start the hybrid sys-
tem.
 Is the message displayed on
the multi-information display?
Check the message on the
multi-information display.
( P.475)
 When a warning light turns on
or a warning message is dis-
played, refer to P.464, 475.
The shift lever cannot be
shifted from P even if you
depress the brake pedal
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 activated and
the horn sounds (if
equipped)
A warning buzzer sounds
when leaving the vehicle
A warning light turns on
or a warning message is
displayed

574Alphabetical Index
Heated steering wheel ........... 361
HeatersFront automatic air conditioning system ................................ 348
Heated steering wheel ......... 361
Outside rear view mirrors ..... 350
Rear automatic air conditioning system ................................ 358
Seat heaters ......................... 361
High mounted stoplight Replacing light bulbs ............ 448
Hill-start assist control .......... 336
Hood ........................................ 410
Hooks Cargo hooks ......................... 372
Coat hooks ........................... 388
Grocery bag hooks ............... 387
Retaining hooks (floor mat) .... 32
Horn ......................................... 187
Hybrid battery (tr action battery)
Location.................................. 83
Specification ......................... 519
Hybrid battery (traction battery) air intake vents ............... 85, 440
Hybrid battery (traction battery) air intake vents and filters ... 440
Hybrid battery air vent ............. 85
Hybrid system .......................... 79 ACC...................................... 237
Acoustic Vehicle Alerting System............................................. 81
Emergency shut off system .... 86
Energy monitor/consumption screen ................................ 122
EV drive mode...................... 239
High voltage components....... 83
How to start the hybrid system ........................................... 234
Hybrid battery (traction battery) air vents.............................. 440
Hybrid Electric Vehicle driving tips...................................... 342 Hybrid System Indicator .97, 101
Hybrid system precautions .....83
If the hybrid sys
tem will not start
...........................................499
If your vehicle has to be stopped in an emergency .................457
Ignition switch (power switch) ...........................................234
Overheating ..........................509
Power (ignition) switch .........234
Regenerative braking .............80
Starting the hybrid system ....234
Hybrid System I ndicator .98, 102,
121
Hybrid transmissio n ...............241
S mode .................................244
I
I/M test .....................................406
Identification Engine ..................................518
Vehicle..................................517
Ignition switch (power switch) ...............................................234Auto power off fun ction.........238
Changing the power switch modes.................................237
If your vehicle has to be stopped in an emergency .................457
Starting the hybrid system ....234
Illuminated entry system .......365
Immobilizer system ..................88
Indicators ..................................94
Initialization Items to initialize ...................551
Maintenance .........................403
Oil maintenance ...................415
Tire pressure warning system...........................................427
Inside rear view m irror ...187, 189
Instrument panel light control99, 103