2012 TOYOTA SIENNA towing

When driving2
211
SIENNA_U (OM45477U)
2-1. Driving proceduresDriving the vehicle............ 212
Engine (ignition) switch (vehicles without smart
key system).................... 226
Engine (ignition) switch (vehicles with smart key
system) .......................... 229
Automatic transaxle ......... 236
Turn signal lever .............. 241
Parking brake ................... 242
Horn ................................. 243
2-2. Instrument cluster and information display
Gauges and meters ......... 244
Indicators and warning lights .............................. 247
Multi-information display............................ 252
2-3. Operating the lights and wipers
Headlight switch ............... 266
Automatic High Beam ...... 273
Fog light switch ................ 280
Windshield wipers and washer ........................... 282
Rear window wiper and washer ........................... 290 2-4. Using other driving systems
Cruise control ................... 293
Dynamic radar cruise control ............................ 298
Intuitive parking assist...... 314
Rear view monitor system ........................... 321
Driving assist systems ..... 327
Hill-start assist control ...... 333
PCS (Pre-Collision System) ... 336
2-5. Driving information Cargo and luggage .......... 343
Vehicle load limits ............ 351
Winter driving tips ............ 352
Trailer towing (with towing package) .... 356
Dinghy towing .................. 376

297
2-4. Using other
driving systems
2
When driving
SIENNA_U (OM45477U)
CAUTION
■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 or during emergency towing

311
2-4. Using other
driving systems
2
When driving
SIENNA_U (OM45477U)
CAUTION
■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.
● 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 an approach warning buzzer is heard often
● When your vehicle is towing a trailer or during emergency towing

344 2-5. Driving information
SIENNA_U (OM45477U)
Capacity and distributionCargo capacity depends on the total weight of the occupants.
(Cargo capacity) = (Total load capacity) - (Total weight of occupants)
Steps for Determining Correct Load Limit 
(1) Locate the statement “The co mbined weight of occupants and
cargo should never exceed XXX kg or XXX lbs.” on your vehi-
cle’s placard.
(2) Determine the combined weight of the driver and passengers that will be riding in your vehicle.
(3) Subtract the combined weight of the driver and passengers from XXX kg or XXX lbs.
(4) The resulting figure equals the available amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals 1400 lbs. and there will
be five 150 lb passengers in your vehicle, the amount of avail-
able cargo and luggage load capacity is 650 lbs. (1400 - 750 (5 
150) = 650 lbs.)
(5) Determine the combined wei ght of luggage and cargo being
loaded on the vehicle. That weig ht may not safely exceed the
available cargo and luggage load capacity calculated in Step 4.
(6) If your vehicle will be towing a trailer, load from your trailer will be transferred to your vehicle. Cons ult this manual to determine how
this reduces the available ca rgo and luggage load capacity of
your vehicle. ( P. 784)

356
2-5. Driving information
SIENNA_U (OM45477U)
Trailer towing (with towing package)
Your vehicle is designed primarily as a passenger-and-load-carrying
vehicle. Towing a trailer can have an adverse impact on handling,
performance, braking, durability, and fuel consumption. For your
safety and the safety of others, you must not overload your vehicle
or trailer. You must also ensure that you are using appropriate tow-
ing equipment, that the towing eq uipment has been installed cor-
rectly and used properly, and that you employ the requisite driving
habits.
Vehicle-trailer stability and br aking performance are affected by
trailer stability, brake performance and setting, trailer brakes, the
hitch and hitch systems (if equipped).
To tow a trailer safely, use extreme care and drive the vehicle in
accordance with your trailer’s characteristics and operating condi-
tions.
Toyota warranties do not apply to damage or malfunction caused by
towing a trailer for commercial purposes.
Contact your Toyota dealer for fu rther information about additional
requirements such as a towing kit, etc.

357
2-5. Driving information
2
When driving
SIENNA_U (OM45477U)
Towing related terms
■ 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 vehicle
weight is the total weight of the
vehicle. When towing a trailer, it
is the sum of the vehicle weight
(including the occupants, cargo
and any optional equipment
installed on the vehicle) and the
tongue weight.

358 2-5. Driving information
SIENNA_U (OM45477U)■
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).
■ 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, towing package
(if available), hitch and hitch sys-
tems (if required).
Additional optional equipment,
passengers and cargo in the vehi-
cle will reduce the trailer weight
rating so as not to exceed
GCWR, GVWR and GAWR.
If the gross trailer weight exceeds
3000 lb. (1360 kg), it is recom-
mended to use a trailer with 2 or
more axles.
Front GAWR
Rear GAWR
(With brakes)

362 2-5. Driving information
SIENNA_U (OM45477U)
Trailer Tongue Weight● A recommended tongue weight varies in accordance with the types
of trailers or towing as described below.
● To ensure the recommended values shown below, the trailer must
be loaded by referring to the following instructions.
• Tongue Weight
The gross trailer weight should be distributed so that the tongue
weight is 9 to 11 %.
(Tongue weight / Gross trailer weight  100 = 9 to 11 %)
Gross trailer weight
Tongue weight
If using a weight distributing hitch when towing, return the front
axle to the same weight as before the trailer connection.
If front axle weight cannot be measured directly, measure the front
fender height above the front axle before connection. Adjust weight
distributing hitch torque until fr ont fender is returned to the same
height as before connection.
The gross trailer weight, gross axle weight and tongue weight can
be measured with platform scales found at a highway weighing sta-
tion, building supply company, trucking company, junk yard, etc.