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337
2-4. Using other
driving systems
2
When driving
SIENNA_U (OM45477U)
Disabling pre-collision braking
Pre-collision braking disabled
Pre-collision braking enabled
The “PCS” warning light flashes
when pre-collision braking is dis-
abled.
Radar sensorThe radar sensor detects vehi-
cles or other obstacles on or
near the road ahead and deter-
mines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles.
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340 2-4. Using other driving systems
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■When there is a malfunction in the system
Warning lights will turn on or flash. ( P. 729)
■ Certification
U.S.A.
FCC ID: HYQDNMWR005
This device complies with part 15 of the FCC Rules. Operation is subject to
the following two conditions: (1) This device may not cause harmful interfer-
ence, and (2) this device must accept any interference received, including
interference that may cause undesired operation.
FCC WARNING
Changes or modifications not expressly approved by the party responsible
for compliance could void the user’s authority to operate the equipment.
Radiofrequency radiation exposure Information:
This equipment complies with FCC radiation exposure limits set forth for an
uncontrolled environment.
This equipment should be installed and operated with minimum distance of
20 cm between the radiator (antenna) and your body.
This transmitter must not be co-located or operating in conjunction with any
other antenna or transmitter.
Canada
Operation is subject to the following two conditions: (1) this device may not
cause interference, and (2) this device must accept any interference, includ-
ing interference that may cause undesired operation of the device.
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342 2-4. Using other driving systems
SIENNA_U (OM45477U)
CAUTION
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effec-
tively:
● Keep the sensor and front grille clean at all times.
Clean the sensor and front grille with a soft cloth so you do not mark or
damage them.
● Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction.
If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by your Toyota dealer.
● Do not disassemble the sensor.
● Do not attach accessories or stickers to the sensor, grille or surrounding
area.
● Do not modify or paint the sensor and grille cover.
Page 363 of 860
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When driving
SIENNA_U (OM45477U)
Hitch
Trailer hitch assemblies have different weight capacities. Toyota rec-
ommends the use of Toyota hitch/brac ket for your vehicle. For details,
contact your Toyota dealer.
● If you wish to install a trailer hitch, contact your Toyota dealer.
● Use only a hitch that conforms to the gross trailer weight require-
ment of your vehicle.
● Follow the directions supplied by the hitch manufacturer.
● Lubricate the hitch ball with a light coating of grease.
● Remove the trailer hitch whenever you are not towing a trailer.
After removing the hitch, seal any mounting hole in the vehicle
body to prevent entry of any substances into the vehicle.
Page 365 of 860
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When driving
SIENNA_U (OM45477U)
Positions for towing hitch receiver
Hitch receiver pin hole posi-
tion: 37.3 in. (949.8 mm)
Connecting trailer lightsPlease consult your dealer when installing trailer lights, as incorrect
installation may cause damage to the vehicle’s lights. Please take
care to comply with your state’ s laws when installing trailer lights.
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366 2-5. Driving information
SIENNA_U (OM45477U)
Trailer towing tipsYour vehicle will handle differently when towing a trailer. Help to avoid
an accident, death or serious injury, keep the following in mind when
towing:
● Speed limits for towing a trailer vary by state or province. Do not
exceed the posted towing speed limit.
● Toyota recommends that the vehicle-trailer speed limit is 65 mph
(104 km/h) on a flat, straight, dry road. Do not exceed this limit, the
posted towing speed limit or the speed limit for your trailer as set
forth in your trailer owner’s man ual, whichever is lowest. Instability
of the towing vehicle-trailer combin ation (trailer sway) increases as
speed increases. Exceeding speed limits may cause loss of con-
trol.
● Before starting out, check the trailer lights, tires and the vehicle-
trailer connections. Recheck after driving a short distance.
● Practice turning, stopping and reve rsing with the trailer attached in
an area away from traffic until you become accustomed to the feel
of the vehicle-trailer combination.
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370 2-5. Driving information
SIENNA_U (OM45477U)
■Matching trailer ball height to trailer coupler height
■ Before towing
Check that the following conditions are met:
● Ensure that your vehicle’s tires are properly inflated. ( P. 794)
● Trailer tires are inflated according to the trailer manufacturer’s recom-
mendation.
● All trailer lights work as required by law.
● All lights work each time you connect them.
● The trailer ball is set at the proper height for the coupler on the trai\
ler.
● The vehicle remains level when a loaded or unloaded trailer is hitched.
Do not drive if the vehicle is not level, and check for improper tongue
weight, overloading, worn suspension, or other possible causes.
● The trailer cargo is securely loaded.
● The rear view mirrors conform to all applicable federal, state/provincial or
local regulations. If they do not, install rear view mirrors appropriate for
towing purposes.
No matter which class of tow hitch
applies, for a safe trailer hookup, the
trailer ball setup on must be proper height
for the coupler on the trailer.
Coupler
Trailer ball
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When driving
SIENNA_U (OM45477U)
CAUTION
■
When towing a trailer
Toyota recommends trailers with brak es 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 wi th 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.