steering TOYOTA SIENNA HYBRID 2021 (in English) Repair Manual

3374-5. Using the driving support systems
4
Driving
*: PCS will also be disabled (only Pre-Collision warning is avail-
able). The PCS warning light will
come on and a message will be
displayed on the multi-information
display. ( P.274)
■When the message is dis-
played on the multi-information
display showing that TRAC has
been disabled even if has
not been pressed
TRAC is temporary deactivated. If
the information continues to show,
contact your Toyota dealer.
■Operating conditions of hill-
start assist control
When the following four conditions
are met, the hill-start assist control
will operate:
●The shift lever is in a position
other than P or N (when starting
off forward/backward on an
upward incline).
●The vehicle is stopped.
●The accelerator pedal is not
depressed.
●The parking brake is not engaged.
■Automatic system cancelation
of hill-start as sist control
The hill-start assis t control will turn
off in any of the following situations:
●The shift lever is shifted to P or N.
●The accelerator pedal is
depressed.
●The parking brake is engaged.
●2 seconds at maximum elapsed
after the brake pedal is released.
■Sounds and vibrations caused
by the ABS, brake assist, VSC,
Trailer Sway Control, TRAC and
hill-start assist control systems
●A sound may be heard from the
engine compartment when the
brake pedal is dep ressed repeat-
edly, when the hybrid system is started or just after the vehicle
begins to move. This sound does
not indicate that a malfunction has
occurred in any of these systems.
●Any of the following conditions
may occur when the above sys-
tems are operating. None of these
indicates that a malfunction has
occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.
■ECB operating sound
ECB operating sound may be heard
in the following cases, but it does
not indicate that a malfunction has
occurred.
●Operating sound heard from the
engine compartment when the
brake pedal is operated.
●Motor sound of the brake system
heard from the f ront part of the
vehicle when the driver’ door is
opened.
●Operating sound heard from the
engine compartment when one or
two minutes passed after the stop
of the hybrid system.
■Active Cornering Assist opera-
tion sounds and vibrations
When the Active Cornering Assist is
operated, operation sounds and
vibrations may be generated from
the brake system, but this is not a
malfunction.
■EPS operation sound
When the steering wheel is oper-
ated, a motor sound (whirring
sound) may be heard. This does not
indicate a malfunction.
■Automatic reactivation of
TRAC, Trailer Sway Control and
VSC systems
After turning the TRAC, Trailer
Sway Control and VSC systems off,
the systems will be a utomatically re-
enabled in the following situations:

3384-5. Using the driving support systems
●When the power switch is turned
off.
●If only the TRAC system is turned
off, the TRAC will turn on when
vehicle speed increases.
If both the TRAC and VSC sys-
tems are turned off, automatic re-
enabling will not occur when vehi-
cle speed increases.
■Operating conditions of Active
Cornering Assist
The system operates when the fol-
lowing occurs.
●TRAC/VSC can operate
●The driver is at tempting to accel-
erate while turning
●The system detects that the vehi-
cle is drifting to the outer side
●The brake pedal is released
■Reduced effectiveness of the
EPS system
The effectiveness of the EPS sys-
tem is reduced to prevent the sys-
tem from overheating when there is
frequent steering input over an
extended period of time. The steer-
ing wheel may feel heavy as a
result. Should this occur, refrain
from excessive steering input or
stop the vehicle and turn the hybrid
system off. The EPS system should
return to normal within 10 minutes.
■Secondary Collision Brake
operating conditions
The system operates when the SRS
airbag sensor de tects a collision
while the vehicle is in motion. How-
ever, the system does not operate in
any of the following situations.
●The vehicle speed is below 6 mph
(10 km/h)
●Components are damaged
■Secondary Collision Brake
automatic cancellation
The system is automatically can-
celed in any of th e following situa-
tions.
●The vehicle speed drops below
approximately 6 mph (10 km/h)
●A certain amount of time elapses
during operation
●The accelerator pedal is
depressed a large amount
■If a message about AWD is
shown on the multi-information
display (AWD models)
If one of the follo wing messages is
shown on the multi-information dis-
play, perform each action.
●“AWD System Overheated
Switching to 2WD Mode”
The AWD system is overheating.
Drive the vehicle at low speeds and
stop the vehicle in a safe place with
the hybrid system operating until the
message is cleared. If the message
disappears, it is possible to drive the
vehicle normally.
●“AWD System Overheated 2WD
Mode Engaged”
The AWD system has been can-
celed and switch ed to the front-
wheel drive due to overheating.
Drive the vehicle at low speeds and
stop the vehicle in a safe place with
the hybrid system operating until the
message is cleared. If the message
disappears, it is possible to drive the
vehicle normally.
●“AWD System Malfunction 2WD
Mode Engaged Visit Your Dealer”
The AWD system has been stopped
and switched to the front-wheel
drive due to a malfunction. Have
your vehicle inspected by your
Toyota dealer immediately.

3404-5. Using the driving support systems
WARNING
■Replacing tires
Make sure that all tires are of the
specified size, brand, tread pat-
tern and total load capacity. In
addition, make sure that the tires
are inflated to the recommended
tire inflation pressure level.
The ABS, TRAC, Trailer Sway
Control and VSC systems will not
function correctly if different tires
are installed on the vehicle.
Contact your Toyota dealer for
further information when replacing
tires or wheels.
■Handling of tires and the sus-
pension
Using tires with any kind of prob-
lem or modifying the suspension
will affect the driving assist sys-
tems, and may cause a system to
malfunction.
■Trailer Sway Control precau-
tion
The Trailer Sway Control system
is not able to reduce trailer sway
in all situations . Depending on
many factors such as the condi-
tions of the vehicle, trailer, road
surface and driving environment,
the Trailer Sway Control system
may not be effective. Refer to
your trailer owner’s manual for
information on how to tow your
trailer properly.
■If trailer sway occurs
Observe the following precau-
tions.
Failing to do so may cause death
or serious injury.
●Firmly grip the steering wheel.
Steer straight ahead. Do not try
to control trailer sway by turning
the steering wheel.
●Begin releasing the accelerator
pedal immediately but very
gradually to reduce speed.
Do not increase speed. Do not
apply vehicle brakes.
If you make no extreme correction
with the steering or brakes, your
vehicle and traile r should stabi-
lize. ( P.220)
■Secondary Collision Brake
Do not rely solely upon the Sec-
ondary Collision Brake. This sys-
tem is designed to help reduce
the possibility of further damage
due to a secondary collision, how-
ever, that effect changes accord-
ing to various conditions. Overly
relying on the system may result
in death or serious injury.

3434-6. Driving tips
4
Driving
Use fluids that are appropriate
to the prevailing outside tem-
peratures.
• Engine oil
• Engine coolant
• Power control unit coolant
• Washer fluid
Have a service technician
inspect the condition of the
12-volt battery.
 Have the vehicle fitted with
four snow tires or purchase a
set of tire chains for the front
tires.
*
Ensure that all tires are the same
size and brand, and that chains
match the size of the tires.
*: Tire chains cannot be mounted
on vehicles with 20-inch tires.
Winter driving tips
Carry out the necessary
preparations and inspec-
tions before driving the
vehicle in winter. Always
drive the vehicle in a man-
ner appropriate to the pre-
vailing weather conditions.
Pre-winter preparations
WARNING
■Driving with snow tires
Observe the following precautions
to reduce the risk of accidents.
Failure to do so may result in a
loss of vehicle control and cause
death or serious injury.
●Use tires of the specified size.
●Maintain the recommended
level of air pressure.
●Do not drive in excess of 75
mph (120 km/h), regardless of
the type of snow tires being
used.
●Use snow tires on all, not just
some wheels.
■Driving with tire chains (vehi-
cles with 17-inch or 18-inch
tires)
Observe the following precautions
to reduce the risk of accidents.
Failure to do so may result in the
vehicle being unable to be driven
safely, and may cause death or
serious injury.
●Do not drive in excess of the
speed limit specifi ed for the tire
chains being used, or 30 mph
(50 km/h), whichever is lower.
●Avoid driving on bumpy road
surfaces or over potholes.
●Avoid sudden acceleration,
abrupt steering, sudden brak-
ing and shifting operations that
cause sudden engine braking.
●Slow down sufficiently before
entering a curve to ensure that
vehicle control is maintained.
●Do not use LTA (Lane Tracing
Assist) system.

347
5
5
Interior features
Interior features
5-1. Using the air conditioning system and defogger
Front automatic air condi- tioning system ........... 348
Rear automatic air condi- tioning system ........... 358
Heated steering wheel/seat heaters/seat ventilators.................................. 361
5-2. Using the interior lights Interior lights list .......... 363
5-3. Using the storage features List of storage features 366
Luggage compartment fea- tures .......................... 372
5-4. Using the other interior features
Other interior features . 374
Garage door opener.... 392

3615-1. Using the air conditioning system and defogger
5
Interior features
*: If equipped
Turns the heated steering wheel
on/off
The indicator light comes on when
the heated steering wheel is oper-
ating.
■Operation condition
The power switch is in ON.
Each time the switch is pressed,
the operation condition changes
as follows.
Hi (3 segments lit)  Mid (2
segments lit)  Lo (1 segment
Heated steering
wheel*/seat heat-
ers*/seat ventilators*
 Heated steering wheel
Warm up the grip of the steer-
ing wheel
 Seat heaters
Warm up the seat upholstery
 Seat ventilators
Maintain good ventilation by
sucking air through the seat
upholstery
WARNING
■To prevent minor burn inju-
ries
Care should be taken if anyone in
the following categories comes in
contact with the steering wheel or
seats when the heater is on:
●Babies, small children, the
elderly, the sick and the physi-
cally challenged
●Persons with sensitive skin
●Persons who are fatigued
●Persons who have taken alco-
hol or drugs that induce sleep
(sleeping drugs, cold remedies,
etc.)
NOTICE
■To prevent damage to the
seat heaters and seat ventila-
tors
Do not put heavy objects that
have an uneven surface on the
seat and do not stick sharp
objects (needles, nails, etc.) into
the seat.
■To prevent 12-volt battery dis-
charge
Do not use the functions when the
hybrid system is off.
Heated steering wheel
Operating the seat heat-
ers

3715-3. Using the storage features
5
Interior features
Front of console box (Type A)
Front of console box (Type B)
Open the lid.
Rear of console box
On the console box
Close the console box.
Under the console box
WARNING
■Items unsuitable for the open
tray
Observe the following precautions
when putting items in the open
tray. Failure to d o so may cause
items to be thrown out of the tray
in the event of s udden braking or
steering. In these cases, the items
may interfere with pedal operation
or cause driver distraction, result-
ing in an accident.
●Do not store ite ms in the tray
that can easily shift or roll out.
●Do not stack items in the tray
higher than the tray’s edge.
●Do not put items in the tray that
may protrude over the tray’s
edge.

4026-1. Maintenance and care
WARNING
■Precaution regarding the rear
bumper with Blind Spot Moni-
tor (if equipped)
If the paint of the rear bumper is
chipped or scratched, the system
may malfunction. If this occurs,
consult your Toyota dealer.
NOTICE
■To prevent paint deterioration
and corrosion on the body
and components (aluminum
wheels, etc.)
●Wash the vehicle immediately in
the following cases:
• After driving near the sea coast
• After driving on salted roads
• If coal tar or tre e sap is present
on the paint surface
• If dead insects, insect droppings or bird droppings are present on
the paint surface
• After driving in an area contami- nated with soot, oily smoke,
mine dust, iron powder or chem-
ical substances
• If the vehicle becomes heavily soiled with dust or mud
• If liquids such as benzene and gasoline are spilled on the paint
surface
●If the paint is chipped or
scratched, have it repaired
immediately.
●To prevent the wheels from cor-
roding, remove any dirt and
store in a place with low humid-
ity when storing the wheels.
■Cleaning the exterior lights
●Wash carefully. Do not use
organic substances or scrub
with a hard brush.
This may damage the surfaces
of the lights.
●Do not apply wax to the sur-
faces of the lights.
Wax may cause damage to the
lenses.
■When using an automatic car
wash (vehicles with rain-
sensing windshield wipers)
Set the wiper switch to off posi-
tion.
If the wiper switch is in “AUTO”,
the wipers may operate and the
wiper blades may be damaged.
■When using a high pressure
car wash
●When washing the vehicle, do
not let water from the high-pres-
sure washer directly hit the
camera or the area around the
camera. Due to the shock from
the high pressure water, it is
possible that the device may not
operate normally.
●Do not bring the nozzle tip close
to boots (rubber or resin manu-
factured cover), or connectors
or the following parts.
The parts may be damaged if
they come into contact with
high-pressure water.
• Traction re lated parts
• Steering parts
• Suspension parts
• Brake parts

4096-2. Maintenance
6
Maintenance and care
Parking brake
• Does the park-ing brake oper-
ate normally?
• When parked on a slope and the
parking brake is
on, is the vehicle
securely
stopped?
Seat belts
• Do the seat belts operate
smoothly?
• The seat belts should not be
damaged.
Seats
• Do the seat con-trols operate
properly?
Steering wheel
• Does the steer-ing wheel rotate
smoothly?
• Does the steer- ing wheel have
the correct
amount of free
play?
• There should not be any strange
sounds coming
from the steer-
ing wheel.
ItemsCheck pointsVehicle exterior
ItemsCheck points
Doors
• Do the doors operate
smoothly?
Engine hood
• Does the engine hood lock system
work properly?
Fluid leaks
• There should not be any signs of
fluid leakage
after the vehicle
has been parked.
Tires
• Is the tire infla-tion pressure
correct?
• The tires should not be damaged
or excessively
worn.
• Have the tires been rotated
according to the
maintenance
schedule?
• The wheel nuts should not be
loose.
Windshield
wipers/rear
window wiper
• The wiper blades should not show
any signs of
cracking, split-
ting, wear, con-
tamination or
deformation.
• The wiper blades should clear the
windshield/rear
window without
streaking or skip-
ping.

4597-1. Essential information
7
When trouble arises
1Steadily step on the brake
pedal with both feet and
firmly depress it.
Do not pump the brake pedal
repeatedly as this will increase the
effort required to slow the vehicle.
2Shift the shift lever to N.
If the shift lever is shifted to N
3 After slowing down, stop the
vehicle in a safe place by the
road.
4 Stop the hybrid system.
If the shift lever cannot be
shifted to N
3 Keep depressing the brake
pedal with both feet to reduce
vehicle speed as much as
possible.
4 Press and hold the power
switch for 2 consecutive sec-
onds or more, or press it briefly 3 times or more in suc-
cession.
5 Stop the vehicle in a safe
place by the road.
If your vehicle has to
be stopped in an emer-
gency
Only in an emergency, such
as if it becomes impossible
to stop the vehicle in the
normal way, stop the vehi-
cle using the following pro-
cedure:
Stopping the vehicle
WARNING
■If the hybrid system has to be
turned off while driving
●Power assist for the steering
wheel will be lost, making the
steering wheel heavier to turn.
Decelerate as much as possible
before turning off the hybrid sys-
tem.