sensor TOYOTA SIENNA HYBRID 2023 Service Manual

2924-5. Using the driving support systems
Indicators
■Operation switchesVehicle-to-vehicle distance
switch
“+RES” switch
Cruise control main switch
Cancel switch
“-SET” switch
WARNING
■Before using dynamic radar
cruise control with full-speed
range
●Driving safely is the sole
responsibility of t he driver. Do
not rely solely o n the system,
and drive safely by always pay-
ing careful attention to your sur-
roundings.
C
A
B
C
D
E
●The dynamic radar cruise con-
trol with full-speed range pro-
vides driving assistance to
reduce the driver’s burden.
However, there ar e limitations
to the assistance provided.
Read the following conditions
carefully. Do not overly rely on
this system and always drive
carefully.
• When the sensor may not be correctly detecting the vehicle
ahead: P.301
• Conditions under which the vehicle-to-vehicle distance con-
trol mode may not function cor-
rectly: P.301
●Set the speed appropriately
depending on the speed limit,
traffic flow, road conditions,
weather conditions, etc. The
driver is responsible for check-
ing the set speed.
●Even when the system is func-
tioning normally, the condition
of the preceding vehicle as
detected by the system may dif-
fer from the condition observed
by the driver. Therefore, the
driver must always remain alert,
assess the danger of each situ-
ation and drive safely. Relying
solely on this system or assum-
ing the system ensures safety
while driving can lead to an
accident, resulting in death or
serious injury.
●Switch the dynamic radar cruise
control with full-speed range
setting to off, using the cruise
control main switch when not in
use.

2944-5. Using the driving support systems
This mode employs a radar to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, determines the current vehicle-
to-vehicle following distance, and operates to maintain a suitable fol-
lowing distance from the vehicle ahead. The desired vehicle-to- vehi-
cle distance can also be set by operating the vehicle-to-vehicle
distance switch.
When driving on downhill slopes, the vehicle-to-vehicle distanc e may
become shorter.
WARNING
●When weather conditions are
bad enough that they may pre-
vent the sensors from detecting
correctly (fog, snow, sandstorm,
heavy rain, etc.)
●When there is rain, snow, etc.
on the front surface of the radar
or front camera
●In traffic conditions that require
frequent repeated acceleration
and deceleration
●When your vehicle is towing a
trailer or during emergency tow-
ing
●When an approach warning
buzzer is heard often
Driving in vehicle-to-vehicle distance control mode

3004-5. Using the driving support systems
setting: P.298
■Dynamic radar cruise control
with full-speed range can be set
when
●The shift lever is in D.
●The desired set speed can be set
when the vehicle speed is approx-
imately 20 mph (30 km/h) or more.
(However, when the vehicle speed
is set while driving at below
approximately 20 mph [30 km/h],
the set speed will be set to
approximately 20 mph [30 km/h].)
■Accelerating after setting the
vehicle speed
The vehicle can accelerate by oper-
ating the accelerator pedal. After
accelerating, the set speed
resumes. However, during vehicle-
to-vehicle distance control mode,
the vehicle spee d may decrease
below the set speed in order to
maintain the distance to the preced-
ing vehicle.
■When the vehicle stops while
follow-up cruising
●Pressing the “+RES” switch while
the vehicle ahead stops will
resume follow-up cruising if the
vehicle ahead starts off within
approximately 3 seconds after the
switch is pressed.
●If the vehicle ahead starts off
within 3 seconds after your vehicle
stops, follow-up cruising will be
resumed.
■Automatic cancelation of vehi-
cle-to-vehicle d istance control
mode
Vehicle-to-vehicle distance control
mode is automatically canceled in
the following situations.
●VSC is activated.
●TRAC is activated for a period of
time.
●W h en t he V S C o r T RA C sys te m is
turned off.
●The sensor cannot detect cor-
rectly because i t is covered in
some way.
●When the brake control or output
restriction control of a driving sup-
port system operates.
(For example: Pre-Collision System,
Drive-Start Control)
●The parking brake is operated.
●The vehicle is stopped by system
control on a steep incline.
●The following are detected when
the vehicle has been stopped by
system control:
• The driver is not wearing a seat
belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes
If vehicle-to-vehicle distance control
mode is automatically canceled for
any reasons other than the above,
there may be a malfunction in the
system. Contact your Toyota dealer.
■Automatic cancelation of con-
stant speed control mode
Constant speed control mode is
automatically cance led in the follow-
ing situations:
●Actual vehicle speed is more than
approximately 10 mph (16 km/h)
below the set vehicle speed.
●Actual vehicle speed falls below
approximately 20 mph (30 km/h).
●VSC is activated.

3014-5. Using the driving support systems
4
Driving
●TRAC is activated for a period of
time.
●When the VSC or TRAC system is
turned off.
●When the brake control or output
restriction control of a driving sup-
port system operates.
(For example: Pre- Collision System,
Drive-Start Control)
●The parking brake is operated.
If constant speed control mode is
automatically canceled for any rea-
sons other than the above, there
may be a malfunction in the system.
Contact your Toyota dealer.
■Brake operation
A brake operation sound may be
heard and the brake pedal response
may change, but the se are not mal-
functions.
■Warning messages and buzzers
for dynamic radar cruise con-
trol with full-speed range
Warning messages and buzzers are
used to indicate a system malfunc-
tion or to inform the driver of the
need for caution while driving. If a
warning message is shown on the
multi-information display, read the
message and follow the instructions.
(  P.268, 475)
■When the sensor may not be
correctly detecting the vehicle
ahead
In the case of the following and
depending on the conditions, oper-
ate the brake pedal when decelera-
tion of the system is insufficient or
operate the accelerator pedal when
acceleration is required.
As the sensor may not be able to
correctly detect these types of vehi-
cles, the approach warning
(  P.298) may not be activated.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same lane
●Vehicles with small rear ends
(trailers with no load on board,
etc.)
●Motorcycles traveling in the same
lane
●When water or snow thrown up by
the surrounding vehicles hinders
the detecting of the sensor
●When your vehicle is pointing
upwards (caused by a heavy load
in the luggage compartment, etc.)
●Preceding vehicle has an
extremely high ground clearance
■Conditions under which the
vehicle-to-vehic
le distance con-
trol mode may not function cor-
rectly
In the case of the following condi-
tions, operate the brake pedal (or
accelerator pedal, depending on the
situation) as necessary.
As the sensor may not be able to

3024-5. Using the driving support systems
correctly detect vehicles ahead, the
system may not operate properly.
●When the road curves or when the
lanes are narrow
●When steering wheel operation or
your position in the lane is unsta-
ble
●When the vehicle ahead of you
decelerates suddenly
●When driving on a road sur-
rounded by a structure, such as in
a tunnel or on a bridge
●While the vehicle speed is
decreasing to the set speed after
the vehicle accelerates by
depressing the accelerator pedal
*: If equipped
BSM (Blind Spot Moni-
tor)*
The Blind Spot Monitor is a
system that has 2 functions:
The BSM (Blind Spot Moni-
tor) function
Assists the driver in making a
decision when changing lanes
 The RCTA (Rear Cross
Traffic Alert) function
Assists the driver when back-
ing up
These functions use the
same sensors.
WARNING
■Cautions regarding the use of
the BSM function
The driver is solely responsible for
safe driving. Always drive safely,
taking care to observe your sur-
roundings.
The BSM function is a supple-
mentary function which alerts the
driver that a vehicle is in a blind
spot of the outside rear view mir-
rors or is approaching rapidly from
behind into a blin d spot. Do not
overly rely on the BSM function.
As the function cannot judge if it is
safe to change lanes, over reli-
ance could lead to an accident
resulting in dea th or serious
injury.
As the system may not function
correctly under certain condi-
tions, the driver’s own visual con-
firmation of safety is necessary.

3044-5. Using the driving support systems
tion//RCTA function will be
enabled automatically.
■Outside rear view mirror indica-
tors visibility
In strong sunlight, the outside rear
view mirror indicato r may be difficult
to see.
■Hearing the RCTA buzzer
The RCTA buzzer may be difficult to
hear over loud noises such as high
audio volume.
■When “Blind Spot Monitor
Unavailable” or “Rear Cross
Traffic Alert Unavailable” is
shown on the multi-information
display
The sensor voltage has become
abnormal, or water, snow, mud,
etc., may be built up in the vicinity of
the sensor area of the rear bumper.
(  P.304)
Removing the water, snow, mud,
etc., from the vicinity of the sensor
area should retur n it to normal.
Also, the sensor may not function
normally when used in extremely
hot or cold weather.
■When “Blind Spot Monitor Mal-
function Visit Your Dealer” or
“Rear Cross Traffic Alert Mal-
function Visit Your Dealer” is
shown on the multi-information
display
There may be a sensor malfunction
or misaligned. Have the vehicle
inspected at a Toyota dealer.
■Customization
Some functions can be customized.
(  P.548)
WARNING
■To ensure the system can
operate properly
Blind Spot Monitor sensors are
installed inside t he left and right
sides of the rear bumper respec-
tively. Observe the following to
ensure the Blind Spot Monitor can
function correctly.
●Keep the sensors and the sur-
rounding areas on the rear
bumper clean at all times.
If a sensor or its surrounding
area on the rear bumper is dirty
or covered with snow, the Blind
Spot Monitor may not operate
and a warning message
(  P.304) will be displayed. In
this situation, clear off the dirt or
snow and drive the vehicle with
the operation conditions of the
BSM function ( P.306) satis-
fied for approximately 10 min-
utes. If the warning message
does not disappear, have the
vehicle inspected by your
Toyota dealer.
●Do not subject a sensor or its
surrounding area on the rear
bumper to a strong impact.
If a sensor is moved even
slightly off position, the system
may malfunction and vehicles
may not be detected correctly.
In the following si tuations, have
your vehicle inspected by your
Toyota dealer.
• A sensor or its surrounding area is subject to a strong impact.

3054-5. Using the driving support systems
4
Driving
■Vehicles that can be detected by the Blind Spot Monitor
The BSM function uses radar sensors to detect the following veh i-
cles traveling in adjacent lanes and advises the driver of the pres-
ence of such vehicles via the indicators on the outside rear vi ew
mirrors.
Vehicles that are traveling in areas that are not visible using the
outside rear view mirrors (the blind spots)
Vehicles that are approaching r apidly from behind in areas that
WARNING

3074-5. Using the driving support systems
4
Driving
●Following vehicles that are in the
same lane*
●Vehicles traveling 2 lanes away
from your vehicle*
●Vehicles which are being over-
taken rapidly by your vehicle
*: Depending on the conditions, detection of a vehicle and/or
object may occur.
■Conditions under which the
system may not function cor-
rectly
●The BSM function may not detect
vehicles correctly in the following
situations:
• When the sensor is misaligned
due to a strong impact to the sen-
sor or its surrounding area
• When mud, snow, ice, a sticker, etc. is covering the sensor or sur-
rounding area on the rear bumper
• When driving on a road surface that is wet with standing water
during bad weather, such as
heavy rain, snow, or fog
• When multiple vehicles are approaching with only a small gap
between each vehicle
• When the distanc e between your
vehicle and a following vehicle is
short
• When there is a significant differ- ence in speed between your vehi-
cle and the vehicle that enters the
detection area
• When the difference in speed
between your vehicle and another
vehicle is changing
• When a vehicle enters a detection
area traveling at about the same
speed as your vehicle
• As your vehicle starts from a stop,
a vehicle remains in the detection
area
• When driving up and down con-
secutive steep inclines, such as
hills, dips in the road, etc.
• When driving on roads with sharp
bends, consecutive curves, or
uneven surfaces
• When vehicle lanes are wide, or when driving on the edge of a
lane, and the vehicle in an adja-
cent lane is far away from your
vehicle
• When an accessory (such as a hitch-mounted bicycle carrier) is
installed to the r ear of the vehicle
• When the vehicl e is heavily
loaded in the luggage compart-
ment
• When there is a significant differ- ence in height between your vehi-
cle and the vehicle that enters the
detection area
• Immediately after the BSM func-
tion/RCTA function are turned on
• When towing a trailer
●Instances of the BSM function
unnecessarily detecting a vehicle
and/or object may increase in the
following situations:
• When the sensor is misaligned due to a strong impact to the sen-
sor or its surrounding area
• When the distance between your vehicle and a guardrail, wall, etc.
that enters the detection area is
short
• When driving up and down con-
secutive steep inclines, such as
hills, dips in the road, etc.
• When vehicle lanes are narrow, or
when driving on the edge of a
lane, and a vehicle traveling in a
lane other than the adjacent lanes
enters the detection area
• When driving on r oads with sharp
bends, consecutive curves, or
uneven surfaces
• When the tires are slipping or spinning
• When the distance between your vehicle and a following vehicle is
short
• When an accessory (such as a hitch-mounted bicycle carrier) is
installed to the r ear of the vehicle
• When the vehicle throws up water
or snow behind.

3084-5. Using the driving support systems
■Operation of the RCTA
function
The RCTA function uses radar
sensors to detect vehicles
approaching from the right or left
at the rear of the vehicle and
alerts the driver of the presence
of such vehicles by flashing the
outside rear view mirror indica-
tors and sounding a buzzer.
Approaching vehicles
Detection areas
■RCTA icon display (if
equipped)
When a vehicle approaching
from the right or left at the rear
of the vehicle is detected, the
following will be displayed on
the audio system screen.
 When the Toyota parking
assist monitor (if equipped) is
displayed 
When the panoramic view
monitor (if equipped) is dis-
played
: The RCTA functi on is malfunc-
tioning ( P.304)
■The RCTA function detec-
tion areas
The areas that vehicles can be
detected in are outlined below.
The buzzer can alert the driver of
faster vehicles approaching from
farther away.
The Rear Cross Traffic
Alert function (if
equipped)
A
B

3094-5. Using the driving support systems
4
Driving
Example:
■The RCTA function is opera-
tional when
The RCTA function operates when
all of the followin g conditions are
met:
●The RCTA function is on.
●The shift lever is in R.
●The vehicle speed is less than
approximately 5 mph (8 km/h).
●The approaching vehicle speed is
between approximately 5 mph (8
km/h) and 17 mph (28 km/h).
■Setting the buzzer volume
The buzzer volume can be adjusted
on the multi-inform ation display.
(  P.112)
■Conditions under which the
system will not detect a vehicle
The RCTA function is not designed
to detect the following types of vehi-
cles and/or objects.
●Vehicles approaching from
directly behind
●Vehicles backing up in a parking
space next to your vehicle
●Vehicles that the sensors cannot
detect due to obstructions
●Guardrails, walls, signs, parked
vehicles and similar stationary
objects
*
●Small motorcycles, bicycles,
pedestrians, etc.*
●Vehicles moving away from your
vehicle
●Vehicles approaching from the
parking spaces nex t to your vehi-
cle
*
●The distance between the sensor
and approaching vehicle gets too
close
*: Depending on conditions, detec- tion of a vehicle and/or object may
occur.
■Situations in which the system
may not operate properly
The RCTA function may not detect
vehicles correctly in the following
situations:
●When the sensor is misaligned
due to a strong impact to the sen-
sor or its surrounding area.
●When mud, snow, ice, a sticker,
etc., is covering the sensor or sur-
rounding area on the rear bumper.
●When driving on a road surface
that is wet with standing water
during bad weather, such as
heavy rain, snow, or fog.
●When multiple vehicles are
approaching with only a small gap
between each vehicle.
●When a vehicle is approaching at
high speed.
●When equipment that may
obstruct a sensor is installed, such
Approach-
ing vehicleSpeed

Approxi- mate
alert dis- tance
Fast18 mph
(28 km/h)65 ft. (20 m)
Slow5 mph (8 km/h)18 ft. (5.5 m)
A