2023 TOYOTA SIENNA HYBRID brakes

2244-1. Before driving
■GCWR (Gross Combination
Weight Rating)
The maximum allowable gross
combination weight. The gross
combination weight is the sum
of the total vehicle weight
(including the occupants, cargo
and any optional equipment
installed on the vehicle) and the
weight of the trailer being towed
(including the cargo in the
trailer).
■GVWR (Gross Vehicle
Weight Rating)
The maximum allowable gross
vehicle weight. The gross vehi-
cle weight is the total weight of
the vehicle. When towing a
trailer, it is the sum of the vehi-
cle weight (including the occu-
pants, cargo and any optional
equipment installed on the vehi-
cle) and the tongue weight.
WARNING
●Vehicle-trailer instability is more
likely on steep long downhills.
Before descending steep or
long downhill grades, slow
down and downshift. Do not
make sudden downshifts when
descending steep or long down-
hill grades. Avoid holding the
brake pedal down too long or
applying the brakes too fre-
quently. This could cause the
brakes to overheat and result in
reduced braking efficiency.
●Vehicles with compact spare
tire: Do not tow a trailer when
the compact spare tire is
installed on your vehicle.
■When towing a trailer
Toyota recommends trailers with
brakes that confor m to any appli-
cable federal and state/provincial
regulations.
●If the gross trailer weight
exceeds unbraked TWR, trailer
brakes are required. Toyota rec-
ommends trailers with brakes
that conform to all applicable
federal and state/provincial reg-
ulations.
●Never tap into y our vehicle’s
hydraulic system, as this will
lower the vehicle’s braking
effectiveness.
●Never tow a trailer without using
a safety chain securely attached
to both the traile r and the vehi-
cle. If damage occurs to the
coupling unit or hitch ball, there
is danger of the trailer wander-
ing into another lane.
Towing related terms

2254-1. Before driving
4
Driving
■GAWR (Gross Axle Weight
Rating)
The maximum allowable gross
axle weight. The gross axle
weight is the load placed on
each axle (front and rear).
Front GAWR
Rear GAWR
■TWR (Trailer Weight Rating)
The maximum allowable gross
trailer weight. The gross trailer
weight is the sum of the trailer
weight and the weight of the
cargo in the trailer.
TWR is calculated assuming
base vehicle with one driver,
one front passenger, hitch and hitch systems (if required).
Additional optional equipment, pas-
sengers and cargo in the vehicle
will reduce the trailer weight rating
so as not to exceed GCWR, GVWR
and GAWR.
If the gross traile
r weight exceeds
3000 lb. (1360 kg ), it is recom-
mended to use a trailer with 2 or
more axles.
(With brakes)
■Unbraked TWR (Unbraked
Trailer Weight Rating)
The trailer weight rating for tow-
ing a trailer without a trailer ser-
vice brake system.
(Without brakes)
■Tongue Weight
The load placed on the trailer
hitch ball. ( P.227)
A
B
A
A

2264-1. Before driving
The gross trailer weight must
never exceed 3500 lb. (1585
kg)
*.
*: The towing package is required.
Toyota does no t recommend tow-
ing with this vehicle without the tow-
ing package.
 The gross combination weight
must never exceed the
GCWR described below:
2WD models
8818 lb. (4000 kg)
*

AWD models
8995 lb. (4080 kg)
*
*
: The towing package is required.
Toyota does no t recommend tow-
ing with this vehicle without the tow-
ing package.
 The gross vehicle weight
must never exceed the
GVWR indicated on the Certi-
fication Label.
 The gross axle weight on
each axle must never exceed
the GAWR indicated on the
Certification Label. 
If the gross trailer weight is
over the unbraked TWR,
trailer service brakes are
required.
 If the gross trailer weight is
over 2000 lbs. (907 kg), a
sway control device with suffi-
cient capacity is required.
Confirm that the gross trailer
weight, gross combination
weight, gross vehicle weight,
gross axle weight and tongue
weight are all within the limits.
■GCWR*
2WD models
8818 lb. (4000 kg)
AWD models
8995 lb. (4080 kg)
*: This model meets the tow-vehicle trailering requirement of SAE
International per SAE J2807.
The towing package is required.
Toyota does not recommend tow-
ing with this vehicle without the tow-
ing package.
Weight limits
GCWR, TWR and
Unbraked TWR

2314-1. Before driving
4
Driving
down too long or applying the
brakes too frequently. This
could cause the brakes to
overheat and result in
reduced braking efficiency.
 Due to the added load of the
trailer, your vehicle’s hybrid
system may overheat on hot
days (at temperatures over
85°F [30°C]) when driving up
a long or steep grade. If the
engine coolant temperature
gauge indicates overheating,
immediately turn off the air
conditioning (if in use), pull
your vehicle off the road and
stop in a safe spot. ( P.509)
 Always place wheel blocks
under both the vehicle’s and
the trailer’s wheels when
parking. Apply the parking
brake firmly, and put the
transmission in P. Avoid park-
ing on a slope, but if unavoid-
able, do so only after
performing the following:
1 Apply the brakes and keep
them applied.
2 Have someone place wheel
blocks under both the vehi-
cle’s and trailer’s wheels.
3 When the wheel blocks are in
place, release the brakes
slowly until the blocks absorb
the load.
4 Apply the parking brake
firmly. 5
Shift into P and turn off the
hybrid system.
 When restarting after parking
on a slope:
1 With the transmission in P,
start the hybrid system. Be
sure to keep the brake pedal
depressed.
2 Shift into a forward gear. If
reversing, shift into R.
3 If the parking brake is in man-
ual mode, release the park-
ing brake. ( P.246)
4 Release the brake pedal, and
slowly pull or back away from
the wheel blocks. Stop and
apply the brakes.
5 Have someone retrieve the
blocks.
■Break-in schedule
If your vehicle is new or equipped
with any new power train compo-
nents (such as an engine, transmis-
sion, differential or wheel bearing),
Toyota recommends that you do not
tow a trailer until the vehicle has
been driven for over 500 miles (800
km).
After the vehicle has been driven for
over 500 miles (800 km), you can
start towing. However, for the next
500 miles (800 km), drive the vehi-
cle at a speed of less than 45 mph
(72 km/h) when towing a trailer, and
avoid full throttle acceleration.
■Maintenance
●If you tow a traile r, your vehicle
will require more fr equent mainte-
nance due to the additional load.
(See “Scheduled Maintenance
Guide” or “Owner ’s Manual Sup-
plement”.)

2324-1. Before driving
●Retighten the fixing bolts of the
towing ball and bracket after
approximately 600 miles (1000
km) of trailer towing.
■If trailer sway occurs
One or more factors (crosswinds,
passing vehicles, rough roads, etc.)
can adversely affect handling of
your vehicle and trailer, causing
instability.
●If trailer swaying occurs:
• Firmly grip the steering wheel. Steer straight ahead.
Do not try to control trailer sway-
ing by turning the steering wheel.
• Begin releasing the accelerator pedal immediately but very gradu-
ally to reduce speed.
Do not increase speed. Do not
apply vehicle brakes.
If you make no ext reme correction
with the steering or brakes, your
vehicle and trailer should stabilize (if
enabled, Trailer Sway Control can
also help to stabilize the vehicle and
trailer.).
●After the trailer swaying has
stopped:
• Stop in a safe place. Get all occu- pants out of the vehicle.
• Check the tires of the vehicle and the trailer.
• Check the load in the trailer.
Make sure the load has not
shifted.
Make sure the tongue weight is
appropriate, if possible.
• Check the load in the vehicle. Make sure the vehicle is not over-
loaded after occupants get in.
If you cannot find any problems, the
speed at which trailer swaying
occurred is beyond the limit of your
particular vehicle- trailer combina-
tion. Drive at a lower speed to pre-
vent instability . Remember that
swaying of the towing vehicle-trailer
increases as speed increases.
Dinghy towing
Your vehicle is not designed
to be dinghy towed (with 4
wheels on the ground)
behind a motor home.
NOTICE
■To avoid serious damage to
your vehicle
Do not tow your vehicle with 4
wheels on the ground.

2494-2. Driving procedures
4
Driving
Turn the brake hold system on
The brake hold standby indicator
(green) comes on. While the
system is holding the brake, the
brake hold operated indicator (yel-
low) comes on.
■Brake hold system operating
conditions
The brake hold system cannot be
turned on in the following condi-
tions:
●The driver’s doo r is not closed.
●The driver is not wearing the seat
belt. If any of the cond
itions above are
detected when the brake hold sys-
tem is enabled, the system will turn
off and the brake hold standby indi-
cator light will go off. In addition, if
any of the conditions are detected
while the system is holding the
brake, a warning buzzer will sound
and a message will be shown on the
multi-information display. The park-
ing brake will then be set automati-
cally.
■Brake hold function
●If the brake pedal is left released
for a period of about 3 minutes
after the system has started hold-
ing the brake, the parking brake
will be set automatically. In this
case, a warning buzzer sounds
and a message is shown on the
multi-information display.
●To turn the syste m off while the
system is holding the brake, firmly
depress the brake pedal and
press the button again.
●The brake hold function may not
hold the vehicle when the vehicle
is on a steep incline. In this situa-
tion, it may be ne cessary for the
driver to apply the brakes. A warn-
ing buzzer will sound and the
multi-information display will
inform the driver of this situation. If
a warning message is shown on
the multi-information display, read
the message and follow the
instructions.
■When the parking brake is set
automatically while the system
is holding the brakes
Perform any of the following opera-
tions to release the parking brake.
●Depress the accelerator pedal.
(The parking brake will not be
released automatically if the seat
belt is not fastened.)
●Operate the parkin g brake switch
with the brake pedal depressed.
Make sure that the parking brake
indicator light goes off. ( P.246)
Brake Hold
The brake hold system
keeps the brake applied
when the shift lever is in D,
S or N with the system on
and the brake pedal has
been depressed to stop the
vehicle. The system
releases the brake when the
accelerator pedal is
depressed with the shift
lever in D or S to allow
smooth start off.
Enabling the system
A
B

2504-2. Driving procedures
■When an inspection at your
Toyota dealer is necessary
When the brake hold standby indi-
cator (green) does not illuminate
even when the brake hold switch is
pressed with the brake hold system
operating conditions met, the sys-
tem may be malfunctioning. Have
the vehicle inspected at your Toyota
dealer.
■If “Brakehold Malfunction Press
Brake to Deactivate Visit Your
Dealer” or “Brakehold Malfunc-
tion Visit Your Dealer” is dis-
played on the multi-information
display
The system may be malfunctioning.
Have the vehicle inspected by your
Toyota dealer.
■Warning messages and buzzers
Warning messages and buzzers are
used to indicate a system malfunc-
tion or to inform the driver of the
need for caution. If a warning mes-
sage is shown on the multi-informa-
tion display, read the message and
follow the instructions.
■If the brake hold operated indi-
cator flashes
 P.469
WARNING
■When the vehicle is on a
steep incline
Take care when using the brake
hold system on a steep incline,
exercise caution. The brake hold
function may not hold brakes in
such situations.
Also, the system may not activate
depending on the angle of the
slope.
■When stopped on a slippery
road
The system cannot stop the vehi-
cle when the gripping ability of the
tires has been exceeded. Do not
use the system w hen stopped on
a slippery road.
NOTICE
■When parking the vehicle
The brake hold system is not
designed for use when parking
the vehicle for a long period of
time. Turning the power switch off
while the system is holding the
brake may release the brake,
which would cause the vehicle to
move. When operating the power
switch, depress the brake pedal,
shift the shift lever to P and set
the parking brake.

2704-5. Using the driving support systems
The system can detect the fol-
lowing:
Vehicles
 Bicyclists
 Pedestrians
■Pre-collision warning
When the system determines
that the possibility of a frontal
collision is high, a buzzer will
sound and a warning message
will be displayed on the multi-
information display to urge the
driver to take evasive action.
■Pre-collision brake assist
When the system determines
that the possibility of a frontal
collision is high, the system
applies greater braking force in
relation to how strongly the
brake pedal is depressed.
■Pre-collision braking
If the system determines that
the possibility of a frontal colli-
sion is extremely high, the
brakes are automatically applied
to help avoid the collision or
reduce the impact of the colli-
sion.
PCS (Pre-Collision Sys-
tem)
The pre-collision system
uses a radar sensor and
front camera to detect
objects ( P.270) in front of
the vehicle. When the sys-
tem determines that the
possibility of a frontal colli-
sion with an object is high,
a warning operates to urge
the driver to take evasive
action and the potential
brake pressure is increased
to help the driver avoid the
collision. If the system
determines that the possi-
bility of a frontal collision
with an object is extremely
high, the brakes are auto-
matically applied to help
avoid the collision or help
reduce the impact of the
collision.
The pre-collision system can
be disabled/enabled and the
warning timing can be
changed. ( P.272)
Detectable objects
System functions