2017 TOYOTA SIENNA trailer

SIENNA_OM_OM08007U_(U)
2214-1. Before driving
4
Driving
■Maintenance
●If you tow a trailer, your vehicle will require more frequent maintenance due
to the additional load. (See “Scheduled Maintenance Guide” or “Owner’s
Manual Supplement”.)
● 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 swaying 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 trailer should stabilize.
● After the trailer swaying has stopped:
• Stop in a safe place. Get all occupants 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 overloaded 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 combination.
Drive at a lower speed to prevent instability. Remember that swaying of the
towing vehicle-trailer increases as speed increases.

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SIENNA_OM_OM08007U_(U)
4-1. Before driving
WARNING
■Trailer towing precautions
To tow a trailer safely, use extreme care and drive the vehicle in accordance
with the trailer’s characteristics and operating conditions. Failure to do so
could cause an accident resulting in death or serious injury. Vehicle stability
and braking performance are affected by trailer stability, brake setting and
performance, and the hitch. Your vehi cle will handle differently when towing
a trailer.
■ To avoid accident or injury
●Do not exceed the TWR, unbraked TWR, GCWR, GVWR or GAWR.
● If the gross trailer weight is over 2000 lb. (907 kg), a sway control device
with sufficient capacity is required.
● Adjust the tongue weight within the appropriate range. Place heavier loads
as close to the trailer axle as possible.
● Do not exceed 65 mph (104 km/h), the posted towing speed limit or the
speed limit for your trailer as set forth in your trailer owner’s manual,
whichever is lowest. Slow down sufficiently before making a turn, in cross-
winds, on wet or slippery surface, etc. to help avoid an accident. If you
experience a vehicle-trailer instability from reducing a certain speed, slow
down and make sure you keep your vehicle speed under the speed of
which you experience the instability.
● Do not make jerky, abrupt or sharp turns.
● Do not apply the brakes suddenly as you may skid, resulting in jackknifing
and loss of vehicle control. This is especially true on wet or slippery sur-
faces.
● Do not exceed the trailer hitch assembly weight, gross vehicle weight,
gross axle weight and trailer tongue weight capacities.

SIENNA_OM_OM08007U_(U)
2234-1. Before driving
4
Driving
WARNING
■To avoid accident or injury
●Do not use cruise control when towing.
● Slow down and downshift before descending steep or long downhill
grades. Do not make sudden downshifts while descending steep or long
downhill grades.
● 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 downhill
grades. Avoid holding the brake pedal down too long or applying the
brakes too frequently. 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.
■ Hitch
Trailer hitch assemblies have different weight capacities established by the
hitch manufacturer. Even though the vehicle may be physically capable of
towing a higher weight, the operator must determine the maximum weight
rating of the particular hitch assembly and never exceed the maximum
weight rating specified for the trailer-hitch. Exceeding the maximum weight
rating set by the trailer-hitch manufacturer can cause an accident resulting
in death or serious personal injuries.
■ When towing a trailer
Toyota recommends trailers with brakes that conform to any applicable fed-
eral and state/provincial regulations.
●If the gross trailer weight exceeds unbraked TWR, trailer brakes are
required. Toyota recommends trailers with brakes that conform to all appli-
cable federal and state/provincial regulations.
● Never tap into your vehicle’s hydraulic system, as this will lower the vehi-
cle’s braking effectiveness.
● Never tow a trailer without using a safety chain securely attached to both
the trailer and the vehicle. If damage occurs to the coupling unit or hitch
ball, there is danger of the trailer wandering into another lane.
NOTICE
■When installing a trailer hitch
Use only the position recommended by your Toyota dealer. Do not install
the trailer hitch on the bumper; this may cause body damage.
■ Do not directly splice trailer lights
Do not directly splice trailer lights. Directly splicing trailer lights may damage
your vehicle’s electrical system and cause a malfunction.

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SIENNA_OM_OM08007U_(U)
4-3. Operating the lights and wipers
●In the situations below, the system may not be able to correctly detect the
surrounding brightness levels, and may flash or expose nearby pedestrians
to the high beam. Therefore, you should consider turning the high beam on
or off manually rather than relying on the Automatic High Beam system.
• In bad weather (rain, snow, fog, sandstorms etc.)
• The windshield is obscured by fog, mist, ice, dirt etc.
• The windshield is cracked or damaged.
• The camera sensor is deformed or dirty.
• Surrounding brightness levels are equal to those of headlights, tail lights
or fog lights.
• Vehicles ahead have headlights that are either switched off, dirty, are changing color, or are not aimed properly.
• When driving through an area of in termittently 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 tracks etc.)
• When frequently and repeatedly taking curves or driving on a winding road
• There is a highly reflective object ahead of the vehicle, such as a sign or a mirror.
• The vehicle’s headlights are damaged or dirty.
• The vehicle is lifting or tilting, 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 dis- tress to other drivers or pedestrians nearby.
■ When the warning message is shown on the multi-information display
P. 562
■ Temporary lowering sensor sensitivity
The sensitivity of the sensor can be temporarily lowered.
To lower the sensitivity, push and hold on the inside rear view mirror for
15 to 20 seconds, and release. The indicator light on the inside rear view mir-
ror will flash to indicate that the sensitivity has been lowered.
When the engine switch is turned to the “LOCK” position (vehicles without a
smart key system) or turned off (vehicles with a smart key system), the sensi-
tivity will be returned to its normal level.
■ Customization
The Automatic High Beam can be turned off.
(Customizable features: P. 631)

SIENNA_OM_OM08007U_(U)
2654-5. Using the driving support systems
4
Driving
WARNING
■To avoid operating the cruise control by mistake
Switch the cruise control off using the “ON-OFF” button when not in use.
■ Situations unsuitable for cruise control
Do not use cruise control in any of the following situations.
Doing so may result in loss of control and could cause an accident resulting
in death or serious injury.
●In heavy traffic
● On roads with sharp bends
● On winding roads
● On slippery roads, such as those covered with rain, ice or snow
● On steep hills
Vehicle speed may exceed the set speed when driving down a steep hill.
● When your vehicle is towing a trailer

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SIENNA_OM_OM08007U_(U)
4-5. Using the driving support systems
WARNING
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
●Roads where there are pedestrians, cyclers, etc.
● In heavy traffic
● On roads with sharp bends
● On winding roads
● On slippery roads, such as those covered with rain, ice or snow
● On steep downhills, or where there are sudden changes between sharp up
and down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
● At entrances to expressways
● When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
● When there is rain, snow, etc. on the front surface of the radar sensor or
camera sensor
● In traffic conditions that require frequent repeated acceleration and decel-
eration
● When an approach warning buzzer is heard often
● When your vehicle is towing a trailer

SIENNA_OM_OM08007U_(U)
2774-5. Using the driving support systems
4
Driving
WARNING
■When the sensor may not be correct ly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the
brake pedal when deceleration 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 vehicles,
the approach warning ( P. 271) may not be activated, which may lead to
an accident resulting in death or serious injury.
● 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

SIENNA_OM_OM08007U_(U)
3054-5. Using the driving support systems
4
Driving
■Conditions that may trigger the system even if there is no possibility of a
collision
In any of the following situations where the frontal area of the radar sensor is
interrupted, the radar sensor may detect possibility of a frontal collision and
the system may be activated.
●When passing by an oncoming vehicle in a curve or a turn to the right or the
left.
● When rapidly approaching an obstacle ahead (e.g. preceding vehicle, toll
gate barrier, etc.)
● When there is a structural object (billboard, low ceiling, fluorescent light,
etc.) above the uphill road ahead
● When driving on a narrow road or through under a low overhead structure
(bridge, tunnel, fly-under, etc.)
● When driving on an uneven road surface
● When there is a metal object, bump, or protrusion on the road surface
● When vehicle’s front part is raised or lowered depending on loading condi-
tions
● When the direction of radar sensor is misaligned by strong impact applied
on an area around the radar sensor, etc.
● When there is an obstacle (guard rail, etc.) by the roadside at the entrance
to a curve
● When the front of your vehicle is pointing upwards (caused by towing a
trailer, during emergency towing or putting a heavy load in the luggage com-
partment etc.)
When the system is activated in the situations described above, there is also
a possibility that the seat belts will retract quickly and the brakes may be
applied with a force greater than normal. When the seat belt is locked in the
retracted position, stop the vehicle in a safe place, release the seat belt and
refasten it.
■ Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may
also be occasions when the radar sens or cannot detect pedestrians, animals,
bicycles, motorcycles, trees, or snowdrifts.
■ Situations in which the pre-collis ion system does not function properly
The system may not function effectively in situations such as the following:
● On roads with sharp bends or uneven surfaces
● If a vehicle suddenly moves in front of your vehicle, such as at an intersec-
tion
● If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
● In inclement weather such as heavy rain, fog, snow or sand storms
● When your vehicle is skidding with the VSC system off
● When the axis of the radar is out of adjustment
● When an extreme change in vehicle height occurs