tow TOYOTA SIENNA HYBRID 2021 (in English) Service Manual

2504-3. Operating the lights and wipers
1With the headlights on, push
the lever away from you to
turn on the high beams.
Pull the lever toward you to the
center position to turn the high
beams off.
2Pull the lever toward you and
release it to flash the high
beams once.
You can flash the high beams with
the headlights on or off.1 Press the Automatic High
Beam switch.
NOTICE
■To prevent 12-volt battery dis-
charge
Do not leave the lights on longer
than necessary when the hybrid
system is not running.
Turning on the high beam
headlights
AHB (Automatic High
Beam)
The Automatic High Beam
uses an in-vehicle front
camera to assess the bright-
ness of streetlights, the
lights of vehicles ahead etc.,
and automatically turns the
high beam on or off as nec-
essary.
WARNING
■Limitations of the Automatic
High Beam
Do not overly rely on the Auto-
matic High Beam. Always drive
safely, taking care to observe
your surroundings and turning the
high beam on or off manually if
necessary.
■To prevent incorrect opera-
tion of the Automatic High
Beam system
Do not overload the vehicle.
Activating the Automatic
High Beam system

2524-3. Operating the lights and wipers
fog, mist, ice, dirt, etc.
• The windshield is cracked or dam- aged
• The front camera is deformed or
dirty
• When the temperature of the front
camera is extremely high
• Surrounding brightness levels are equal to those of h eadlights, tail
lights or fog lights
• When headlights or tail lights of vehicles ahead are turned off,
dirty, changing color, or not aimed
properly
• When the vehicle is hit by water,
snow, dust, etc. fr om a preceding
vehicle
• When driving thr ough an area of
intermittently changing brightness
and darkness
• When frequently and repeatedly
driving ascending/descending
roads, or roads with rough, bumpy
or uneven surfaces (such as
stone-paved roads, gravel roads,
etc.)
• When frequently and repeatedly
taking curves or driving on a wind-
ing road
• There is a highly reflective object
ahead of the vehicle, such as a
sign or mirror
• The back of a vehicle ahead is
highly reflective, such as a con-
tainer on a truck
• The vehicle’s headlights are dam-
aged or dirty, or are not aimed
properly
• The vehicle is listing or titling due
to a flat tire, a trailer being towed,
etc.
• The high beam and low beam are
repeatedly being switched
between in an abnormal manner
• The driver believes that the high
beam may be causing problems
or distress to other drivers or
pedestrians nearby
■Temporarily lowering sensor
sensitivity
The sensitivity of the sensor can be
temporarily lowered. 1
Turn the power s witch off while
the following conditions are met.
●The headlight switch is in or
position.
●The headlight switch lever is in the
original position.
●Automatic High Beam switch is
on.
2 Turn the power switch to ON.
3 Within 60 seconds after step 2,
repeat pushing the headlight
switch lever to the high beam
position then pulling it to the orig-
inal position quickly 10 times,
then leave the lever in the origi-
nal position.
4 If the sensitivity is changed, the
Automatic High Beam indicator
turns on and off 3 times.
■Switching to the high
beams
Push the lever away from you.
The Automatic High Beam indicator
will turn off and the headlight high
beam indicator will turn on.
Pull the lever to its original position
to activate the Automatic High
Beam system again.
■Switching to the low beams
Press the Automatic High Beam
Turning the high beam
on/off manually

2534-3. Operating the lights and wipers
4
Driving
switch.
The Automatic High Beam indicator
will turn off.
Press the switch to activate the
Automatic High Beam system
again.
■Temporarily switching to
the low beams
Pull the lever toward you and
then return it to its original posi-
tion.
The high beams are on while the
lever is pulled toward you, how-
ever, after the lever is returned to
its original position, the low beams
remain on for a certain amount of
time. Afterwards, the Automatic
High Beam will be a ctivated again.
■Temporarily switching to the
low beams
It is recommended to switch to the
low beams when the high beam
may cause problems or distress to other drivers or
pedestrians nearby.

2684-5. Using the driving support systems
WARNING
■Limitations of the pre-colli-
sion system
●The driver is solely responsible
for safe driving. Always drive
safely, taking care to observe
your surroundings.
Do not use the pre-collision sys-
tem instead of normal braking
operations under any circum-
stances. This system will not
prevent collisions or lessen col-
lision damage or injury in every
situation. Do not overly rely on
this system. Failure to do so
may lead to an accident, result-
ing in death or serious injury.
●Although this system is
designed to help avoid a colli-
sion or help reduce the impact
of the collision, its effectiveness
may change according to vari-
ous conditions, therefore the
system may not always be able
to achieve the same level of
performance.
Read the following conditions
carefully. Do not overly rely on
this system and always drive
carefully.
• Conditions under which the sys- tem may operate even if there is
no possibility of a collision:
 P.271
• Conditions under which the sys- tem may not operate properly:
 P.272
●Do not attempt to test the oper-
ation of the pre-collision system
yourself.
Depending on the objects used
for testing (dummies, card-
board objects imitating detect-
able objects, etc.), the system
may not operate properly, pos-
sibly leading to an accident.
■Pre-collision braking
●When the pre-collision braking
function is operating, a large
amount of braking force will be
applied.
●If the vehicle is stopped by the
operation of the pre-collision
braking function, the pre-colli-
sion braking function operation
will be canceled after approxi-
mately 2 seconds. Depress the
brake pedal as necessary.
●The pre-collision braking func-
tion may not operate if certain
operations are performed by the
driver. If the accelerator pedal is
being depressed strongly or the
steering wheel is being turned,
the system may determine that
the driver is taking evasive
action and possibly prevent the
pre-collision braking function
from operating.
●In some situations, while the
pre-collision brak ing function is
operating, operation of the func-
tion may be canceled if the
accelerator pedal is depressed
strongly or the steering wheel is
turned and the system deter-
mines that the driver is taking
evasive action.
●If the brake pedal is being
depressed, the system may
determine that t he driver is tak-
ing evasive action and possibly
delay the operation timing of the
pre-collision braking function.
■When to disable the pre-colli-
sion system
In the following situations, disable
the system, as it may not operate
properly, possibly leading to an
accident resulting in death or seri-
ous injury:
●When the vehicle is being towed

2694-5. Using the driving support systems
4
Driving
■Enabling/disabling the pre-
collision system
The pre-collision system can be
enabled/disabled on the
screen ( P.112) of the multi-
information display.
The system is automatically
enabled each time the power
switch is turned to ON.
If the system is disabled, the
PCS warning light will turn on
and a message will be displayed
on the multi-information display.
■Changing the pre-collision
warning timing
The pre-collision warning timing
can be changed on the
screen ( P.112) of the multi-
information display.
The warning timing setting is
retained when the power switch is
turned to OFF. However, if the pre-
collision system is disabled and re-
enabled, the operation timing will
return to the default setting (mid-
dle).
WARNING
●When your vehicle is towing
another vehicle
●When transporting the vehicle
via truck, boat, train or similar
means of transportation
●When the vehicle is raised on a
lift with the hybrid system on
and the tires are allowed to
rotate freely
●When inspecting the vehicle
using a drum tester such as a
chassis dynamometer or speed-
ometer tester, or when using an
on vehicle wheel balancer
●When a strong impact is applied
to the front bumper or front
grille, due to a n accident or
other reasons
●If the vehicle cannot be driven in
a stable manner, such as when
the vehicle has been in an acci-
dent or is malfunctioning
●When the vehicle is driven in a
sporty manner or off-road
●When the tires are not properly
inflated
●When the tires are very worn
●When tires of a size other than
specified are installed
●When tire chains are installed
●When a compact spare tire or
an emergency tire puncture
repair kit is used
●If equipment (snow plow, etc.)
that may obstruct the radar sen-
sor or front camera is temporar-
ily installed to the vehicle
Changing settings of the
pre-collision system

2724-5. Using the driving support systems
the entrance of a curve
• When there are patterns or paint in front of your vehicle that may be
mistaken for a detectable object
• When the front of your vehicle is
hit by water, snow, dust, etc.
• When overtaking a detectable object that is ch anging lanes or
making a right/left turn
• When passing a detectable object in an oncoming lane that is
stopped to make a right/left turn
• When a detectable object approaches very close and then
stops before entering the path of
your vehicle
• If the front of your vehicle is raised or lowered, such as when on an
uneven or undulating road surface
• When driving on a road sur- rounded by a structure, such as in
a tunnel or on an iron bridge
• When there is a metal object (manhole cover, steel plate, etc.),
steps, or a protrusion in front of your vehicle
• When passing under an object (road sign, billboard, etc.)
• When approaching an electric toll gate barrier, parking area barrier,
or other barrier that opens and
closes
• When using an automatic car
wash
• When driving through or under objects that may contact your
vehicle, such as thick grass, tree
branches, or a banner
• When driving through steam or smoke
• When driving near an object that
reflects radio waves, such as a
large truck or guardrail
• When driving near a TV tower,
broadcasting station, electric
power plant, or other location
where strong radio waves or elec-
trical noise may be present
■Situations in which the system
may not operate properly
●In some situations such as the fol-
lowing, an object may not be
detected by the radar sensor and
front camera, pre venting the sys-
tem from opera ting properly:
• When a detectable object is approaching your vehicle
• When your vehicle or a detectable object is wobbling

2764-5. Using the driving support systems
WARNING
●Vehicle is driven in a construc-
tion zone.
●A spare tire, tire chains, etc. are
equipped.
●When the tires have been
excessively worn, or when the
tire inflation pressure is low.
●When your vehicle is towing a
trailer or during emergency tow-
ing
■Preventing LTA system mal-
functions and operations per-
formed by mistake
●Do not modify the headlights or
place stickers, etc. on the sur-
face of the lights.
●Do not modify the suspension
etc. If the suspension etc. needs
to be replaced, contact your
Toyota dealer.
●Do not install or place anything
on the hood or grille. Also, do
not install a grille guard (bull
bars, kangaroo bar, etc.).
●If your windshield needs
repairs, contact your Toyota
dealer.
■Conditions in which functions
may not operate properly
In the following situations, the
functions may not operate prop-
erly and the vehicle may depart
from its lane. Drive safely by
always paying careful attention to
your surroundings and operate
the steering wheel to correct the
path of the vehicle without relying
solely on the functions.
●When the follow-up cruising dis-
play is displayed ( P.281) and
the preceding vehicle changes
lanes. (Your veh icle may follow
the preceding vehicle and also
change lanes.)
●When the follow-up cruising dis-
play is displayed ( P.281) and
the preceding vehicle is sway-
ing. (Your vehicle may sway
accordingly and depart from the
lane.)
●When the follow-up cruising dis-
play is displayed ( P.281) and
the preceding vehicle departs
from its lane. (Your vehicle may
follow the preceding vehicle and
depart from the lane.)
●When the follow-up cruising dis-
play is displayed ( P.281) and
the preceding vehicle is being
driven extremely close to the
left/right lane line. (Your vehicle
may follow the preceding vehi-
cle and depart from the lane.)
●Vehicle is being driven around a
sharp curve.

2914-5. Using the driving support systems
4
Driving
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
Multi-information display
Turning the BSM function/RCTA
function on/off.
Outside rear view mirror indi-cators
BSM function:
When a vehicle is detected in a
blind spot of the outside rear view
mirrors or approaching rapidly from
behind into a blind spot, the outside
rear view mirror indicator on the
detected side will illuminate. If the
turn signal lever is operated toward
the detected side, the outside rear
view mirror indicator will flash.
RCTA function:
When a vehicle approaching from
the right or left at the rear of the
vehicle is detected, both outside
rear view mirror indicators will flash.
BSM OFF indicator/RCTA
OFF indicator
When the Blind Spot Monitor is dis-
abled, the BSM OFF
indicator illu-
minates.
When the RCTA function is dis-
abled, the RCTA OFF indicator illu-
minates.
Monitor screen display
(RCTA function only)
If a vehicle approaching from the
right or left at the rear of the vehicle
is detected, the RCTA icon
(  P.305) for the detected side will
be displayed.
RCTA buzzer (RCTA func-
tion only)
If a vehicle approaching from the
right or left at the rear of the vehicle
is detected, a buzzer will sound
from behind the rear seat.
WARNING
■Cautions regarding the use of
the RCTA function
The driver is solely responsible for
safe driving. Always drive safely,
taking care to o bserve your sur-
roundings.
The RCTA function is only a sup-
plementary function which alerts
the driver tha t a vehicle is
approaching from the right or left
at the rear of the vehicle. As the
RCTA function may not function
correctly under certain condi-
tions, the driver’s own visual con-
firmation of safety is necessary.
Over reliance on this function may
lead to an accident resulting
death or serious injury.
System components
A
B
C
D
E

3054-5. Using the driving support systems
4
Driving
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 vehicle 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 distanc e between your
vehicle and a guar drail, 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 roads with sharp bends, consecutive curves, or
uneven surfaces
• When the tires are slipping or spinning
• When the distanc e 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.
■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
The Rear Cross Traffic
Alert function (if
equipped)
A
B