2012 TOYOTA SIENNA suspension

182 1-7. Safety information
SIENNA_U (OM45477U)
CAUTION
■Modification and disposal of SRS airbag system components
Do not dispose of your vehicle or perform any of the following modifications
without consulting your Toyota dealer.
The SRS airbags may malfunction or deploy (inflate) accidentally, causing
death or serious injury.
● Installation, removal, disassembly and repair of the SRS airbags.
● Repairs, modifications, removal or replacement of the steering wheel,
instrument panel, dashboard, seats or seat upholstery, front, side and rear
pillars or roof side rails.
● Repairs or modifications of the front fender, front bumper, or side of the
occupant compartment.
● Installation of snow plows, winches, etc. to the front grille (bull bars, kan-
garoo bar etc.).
● Modifications to the vehicle’s suspension system.
● Installation of electronic devices such as mobile two-way radios or CD
players.
● Modifications to your vehicle for a person with a physical disability.

225
2-1. Driving procedures
2
When driving
SIENNA_U (OM45477U)
NOTICE
■
When encountering flooded roads
Do not drive on a road that has flooded after heavy rain etc. Doing so may
cause the following serious damage to the vehicle:
● Engine stalling
● Short in electrical components
● Engine damage caused by water immersion
In the event that you drive on a flooded road and the vehicle is flooded, be
sure to have your Toyota dealer check the following:
● Brake function
● Changes in quantity and quality of oil and fluid used for the engine, tran-
saxle, transfer (AWD models), rear differential (AWD models), etc.
● Lubricant condition for the propeller shaft (AWD models), bearings and
suspension joints (where possible) and the function of all joints, bearings,
etc.

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.

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

5
When trouble arises
727
5-1. Essential information
SIENNA_U (OM45477U)
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Toyota dealer as soon as
possible.
■ Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air cond itioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature g auge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, s pongy feeling, pedal almost
touches the floor