2012 TOYOTA SIENNA 4WD

328 2-4. Using other driving systems
SIENNA_U (OM45477U)
When the Enhanced VSC/TRAC systems are operatingIf the vehicle is in danger of slip-
ping or if any of the drive wheels
spins, the slip indicator light
flashes to indicate that the
Enhanced VSC/TRAC systems
are operating.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
■Active Torque Control 4WD (AWD models only)
Automatically switches from front-wheel drive to AWD (All-Wheel Drive)
according to driving conditions, helping to ensure reliable handling and
stability. Examples of conditions where the system will switch to AWD
are when cornering, going uphill, star ting off or accelerating, and when
the road surface is slippery due to snow or rain etc.
■ VDIM (Vehicle Dynamics In tegrated Management) (if
equipped)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-
start assist control, and EPS systems
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes and engine output
■ PCS (Pre-Collision System) (if equipped)
P. 336

332 2-4. Using other driving systems
SIENNA_U (OM45477U)
CAUTION
■When Enhanced VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive
carefully. Reckless driving may cause an accident. Exercise particular care
when the indicator light flashes and a buzzer sounds.
■ When TRAC and VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are the systems to ensure vehicle stability and driving force,
do not turn the TRAC and VSC systems off unless necessary.
■ Replacing tires
Make sure that all tires are of the specified size and of the same brand, tread
pattern and total load capacity. In addition, make sure that the tires are
inflated to the recommended tire pressure level.
The ABS and Enhanced 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 suspension
Using tires with any kind of problem or modifying the suspension will affect
the driving assist systems, and may cause the system to malfunction.
■ Active Torque Control 4WD system
● The AWD system of this vehicle is intended to ensure driving stability on
normal roads. It is not designed for use in demanding situations such as
rally driving.
● Take care when driving on slippery road surfaces.

376
2-5. Driving information
SIENNA_U (OM45477U)
Dinghy towing
NOTICE
■To avoid serious damage to your vehicle
■ To prevent causing serious damage to the transaxle and Active Torque
Control 4WD system (AWD models)
Your vehicle is not designed to be dinghy towed (with 4 wheels on
the ground) behind a motor home.
Do not tow your vehicle with four wheels
on the ground.
ITN25N009
2WD models: Never tow this vehicle from
the rear with the front wheels on the
ground. This may cause serious damage
to the transaxle.
AWD models: Never tow this vehicle with
any of the wheels on the ground. This
may cause serious damage to the tran-
saxle and Active Torque Control 4WD
system.
ITN25N010
ITN25N011

705
4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_U (OM45477U)
FuseAmpereCircuit
6 ECU-IG NO.1 10 A Multiplex communication system,
stop lights, navigation system,
vehicle stability control system,
Active Torque Control 4WD, intui-
tive parking assist, auto anti-glare
inside rear view mirror, pre-collision
seat belt, outside rear view mirror,
seat heater, TPMS, yaw rate & G
sensor, steering angle sensor,
AUTO ACCESS SEAT, main body
ECU
7 P/W RL 20 A Rear power windows (left-side)
8 D/L 15 A Power door lock system
9 P/SEAT FR 30 A Power front seat (right-side)
10 S/ROOF 30 A Moon roof 11 P/W RR 20 A Rear power windows (right-side)
12 P/W FR 20 A Front power windows (right-side)
13 P/SEAT FL 30 A Power front seat (left-side), driving
position memory system
14 STOP 10 A Stop lights, ABS, vehicle stability
control system, rear combination
light, high mounted stop light, auto-
matic transaxle, shift lock system,
multiplex communication system,
power third seat switch, multiport
fuel injection system/sequential
multiport fuel injection system,
trailer lights (stop lights)
15 P/W FL 20 A Front power windows (left-side)

706 4-3. Do-it-yourself maintenance
SIENNA_U (OM45477U)
FuseAmpereCircuit
16 PSD LH 25 A Power sliding door (left-side)
17 4WD 7.5 A Active Torque Control 4WD
18 AM1 10 A Starting system
19 GAUGE NO.2 7.5 A Gauges and meters, multi informa-
tion display
20 IG2 7.5 A Automatic transaxle, multiport fuel
injection system/sequential multi-
port fuel injection system, SRS air-
bag system, front passenger
occupant classification system,
steering lock system, smart key
system, starting system, fuel pump
21 PANEL 10 A Air conditioning system, navigation
system, front passenger’s seat belt
reminder light, audio system, steer-
ing switch, intuitive parking assist
switch, personal/interior light main
switch, shift lever light, headlight
levering switch, power door lock
main switch, clock, power quarter
window switch, seat heater switch,
emergency flashers, rear window
defogger switch, vehicle stability
control off switch, console box light,
power slide switch light

726 5-1. Essential information
SIENNA_U (OM45477U)
NOTICE
■To prevent body damage when towing with a sling-type truck
Do not tow with a sling-type truck, either from the front or rear.
■ To prevent causing serious damage to the transaxle and Active Torque
Control 4WD system (AWD models) wh en towing using a wheel-lift type
truck
■ To prevent damaging the vehicle wh en towing using a wheel-lift type
truck
When raising the vehicle, ensure adequate ground clearance for towing at
the opposite end of the raised vehicle. Without adequate clearance, the
vehicle could be damaged while being towed.
■ Recreational towing (beh ind motor home, etc.)
Never dinghy tow your vehicle to prevent causing serious damage to the
Active Torque Control 4WD system (AWD models) and transaxle. ( P. 376)
2WD models: Never tow this vehicle from
the rear with the front wheels on the
ground. This may cause serious damage
to the transaxle. If towing from the rear,
use a towing dolly.
AWD models: Never tow this vehicle with
any of the wheels on the ground. This
may cause serious damage to the tran-
saxle and Active Torque Control 4WD
system. Use a towing dolly.
ITN51N007
ITN51N008

736 5-2. Steps to take in an emergency
SIENNA_U (OM45477U)
*1:Open door warning buzzer:A buzzer will sound if the vehicle reaches a speed of 3 mph (5 km/h) with any
door open.
*2:Driver’s and front passenger’s seat belt warning buzzers:The driver’s and front passenger’s seat belt warning buzzers sound to alert
the driver and front passenger that his or her seat belt is not fastened. The
buzzer sounds intermittently for 10 seconds after the vehicle has reached a
speed of 12 mph (20 km/h). Then, if the seat belt is still unfastened, the
buzzer will sound at a different tone for 20 more seconds.
*3:Refer to the separate “Scheduled Maintenance Guide” or “Owner’s ManualSupplement” for the maintenance interval applicable to your vehicle.
Warning lightWarning light/DetailsCorrection procedure
(AWD models) Active Torque Control
4WD system warning light
When the light blinks: The
system has been over-
loaded and front-wheel
drive has been automati-
cally engaged. Drop your speed or stop the
vehicle until the light stops
blinking. (Do not stop the
engine.)
When the light comes on:
Malfunction in the Active
Torque Control 4WD sys-
tem. Have the system checked
by your Toyota dealer.

844
SIENNA_U (OM45477U)
Alphabetical index
Alphabetical index
A/C .....................380, 388, 398, 401
ABS ...........................................327
Active head restraint ................. 98
Active Torque Control 4WD system ...........................328
Air conditioning filter............... 690
Air conditioning system Air conditioning filter ..............690
Front automatic air
conditioning system ............388
Front manual air conditioning system ............380
Rear automatic air conditioning system ............401
Rear manual air
conditioning system ............398
Airbags Airbag operating
conditions............................ 173
Airbag precautions for your child ....................... 177
Airbag warning light............... 730
Curtain shield airbag operating conditions............173
Curtain shield airbag precautions .........................177
Front passenger occupant
classification system ...........183
General airbag precautions .........................177
Locations of airbags ..............168
Modification and disposal of airbags ..............182
Proper driving posture ........................166, 177
Side and curtain shield
airbags operating
conditions............................ 173
Side and curtain shield
airbags precautions ............177
SRS airbags .......................... 168 Alarm......................................... 162
Antenna ............................ 418, 467
Anti-lock brake system ........... 327
Armrest ..................................... 600
Audio input ............................... 462
Audio system
A/V input port ........................ 516
Antenna................................. 418
Audio input ............................ 462
Audio visual input .................. 516
AUX port ............................... 462
CD player/changer ................ 422
DVD player.... 499, 509, 513, 514
iPod ....................................... 442
MP3/WMA disc ..................... 431
Optimal use ........................... 457
Portable music player ........... 462
Radio..................................... 412
Rear seat entertainment system ......... 488
Steering wheel audio
switch.................................. 463
Type ...................................... 407
USB memory......................... 449
Audio visual input.................... 462
Automatic light control system .................................... 266
Automatic transaxle Automatic transaxle .............. 236
If the shift lever cannot be shifted from P ..................... 764
S mode.................................. 238
Auxiliary box ........................... 585
AUX port ................................... 462
A/V input port ........................... 462A