2008 TOYOTA SIENNA ecu

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CAUTION
When you load cargo on the roof lug-
gage carrier, observe the following:
Place the cargo so that its weight
is distributed evenly between the
front and rear axles.
If loading long or wide cargo, never
exceed the vehicle overall length or
width. (See “Dimensions and
weights” on page 548 in Section 8
for information on your vehicle
overall length and width.)
Before driving, make sure the cargo
is securely fastened on the roof
luggage carrier.
Loading cargo on the roof luggage
carrier will make the center of the
vehicle gravity higher. Avoid high
speeds, sudden starts, sharp turns,
sudden braking or abrupt maneu-
vers, otherwise it may result in loss
of control or vehicle rollover due to
failure to operate this vehicle cor-
rectly.
If driving for a long distance, on
rough roads, or at high speeds,
stop the vehicle now and then dur-
ing the trip to make sure the cargo
remains in its place.
Do not exceed 68 kg (150 lb.) cargo
weight on the roof luggage carrier.
NOTICE
When loading the luggages, be careful
not to scratch the surface of the
moon roof.
Rear window
Quarter window
Su n sh ad e

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Ti r e relat ed ter mMeaning
Te s t r i mthe rim on which a tire is fitted for testing, and may be any rim listed as appropri-
ate for use with that tire
Treadthat portion of a tire that comes into contact with the road
Tread riba tread section running circumferentially around a tire
Tread separationpulling away of the tread from the tire carcass
Treadwear indicators (TWI)the projections within the principal grooves designed to give a visual indication
of the degrees of wear of the tread
Wheel−holding fixturethe fixture used to hold the wheel and tire assembly securely during testing
Table 1—Occupant loading and distribution for vehicle normal load for various designated seating capacities
Designated seating capacity,number of occupants
Vehicle normal load, number of occupantsOccupant distribution in a normallyloaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
11 through 1552 in front, 1 in second seat, 1 in third
seat, 1 in fourth seat
16 through 2072 in front, 2 in second seat, 2 in third
seat, 1 in fourth seat

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CAUTION
Before driving off, make sure that
the parking brake is fully released
and the parking brake reminder
light is off.
Do not leave your vehicle unat-
tended while the engine is running.
Do not rest your foot on the brake
pedal while driving. It can cause
dangerous overheating, needless
wear, and poor fuel economy.
To drive down a long or steep hill,
reduce your speed and downshift.
Remember, if you ride the brakes
excessively, they may overheat and
not work properly.
Be careful when accelerating, up-
shifting, downshifting or braking on
a slippery surface. Sudden accelera-
tion or engine braking could cause
the vehicle to skid or spin.
Do not drive in excess of the speed
limit. Even if the legal speed limit
permits it, do not drive over 140
km/h (85 mph) unless your vehicle
has highspeed capability tires.
Driving over 140 km/h (85 mph) may
result in tire failure, loss of control
and possible injury. Be sure to con-
sult a tire dealer to determine
whether the tires on your vehicle
are highspeed capability tires or
not before driving at such speeds.
Do not continue normal driving
when the brakes are wet. If they are
wet, your vehicle will require a
longer stopping distance, and it
may pull to one side when the
brakes are applied. Also, the park-
ing brake will not hold the vehicle
securely.
Driving on a slippery road surface
Drive carefully when it is raining, because
visibility will be reduced, the windows may
become fogged−up, and the road will be
slippery.
Drive carefully when it starts to rain,
because the road surface will be espe-
cially slippery.
Refrain from high speeds when driving
on an expressway in the rain, because
there may be a layer of water between
the tires and the road surface,
preventing the steering and brakes
from operating properly.
Driving in the rain

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Total trailer weight Tongue loadTongue load
Total trailer weight 
100 = 9 to 11%
(∗
1)
or 15% (∗
2)
The trailer cargo load should be
distributed so that the tongue load
is 9 to 11% for weight carrying
hitch
(∗
1) or 15% for weight distrib-
ut i ng hi t ch ( ∗
2) of the total trailer
weight, not exceeding the maximum
load of the following.
Weight carrying hitch Without towing package 54 kg (120 lb.)
With towing package 158 kg (350 lb.)
Weight distributing hitch
With towing package 238 kg (525 lb.)
Never load the trailer with more
weight in the back than in the
front. About 60% of the trailer load
should be in the front half of the
trailer and the remaining 40% in the
rear.
HITCHES
If you wish to install a trailer hitch, you
should consult with your Toyota dealer.
Use only a hitch recommended by the
hitch manufacturer and the one which
conforms to the total trailer weight
requirement.
The hitch must be bolted securely to
the vehicle frame and installed accord-
ing to the hitch manufacturer ’s instruc-
tions.
The hitch ball and king pin should have
a light coat of grease.
Toyota recommends removing the trail-
er hitch whenever you are not towing
a trailer to reduce the possibility of
additional damage caused by the hitch
if your vehicle is struck from behind.
After removing the hitch, seal any
mounting holes in the vehicle body to
prevent entry of pollutants such as ex-
haust fumes, dirt, water, etc.
NOTICE
Do not use axlemounted hitches as
they can cause damage to the axle
housing, wheel bearings, wheels or
tires. Also, never install a hitch which
may interfere with the normal function
of an Energy Absorbing Bumper, if so
equipped.
BRAKES AND SAFETY CHAINS
Toyota recommends trailers with
brakes that conform to any applica-
ble federal and state/provincial regu-
lations.

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A safety chain must always be used
between the towing vehicle and the
trailer. Leave sufficient slack in the
chain for turns. The chain should
cross under the trailer tongue to
prevent the tongue from dropping to
the ground in case it becomes dam-
aged or separated. For correct safety
chain procedures, follow the hitch or
trailer manufacturer ’s recommenda-
tions.
CAUTION
If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.
Never tap into your vehicle’s hy-
draulic system as it would lower its
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 over into another
lane.
TIRES
Ensure that your vehicle’s tires are
properly inflated. See page 523 in Sec-
tion 7−2 and page 553 in Section 8 for
instructions.
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.
TRAILER LIGHTS
Trailer lights must comply with federal,
state/provincial and local regulations.
See your local recreational vehicle
dealer or rental agency for the correct
type of wiring and relays for your trail-
er. Check for correct operation of the
turn signals and stop lights each time
you hitch up. Direct splicing may dam-
age your vehicle’s electrical system
and cause a malfunction of your lights.
BREAKIN SCHEDULE
Toyota recommends that you do not
tow a trailer with a new vehicle or a
vehicle with any new power train com-
ponent (engine, transmission, differen-
tial, wheel bearing, etc.) for the first
800 km (500 miles) of driving. MAINTENANCE
If you tow a trailer, your vehicle will
require more frequent maintenance due
to the additional load. For this
information, please refer to the
scheduled maintenance information in
the “Scheduled Maintenance Guide” or
“Owner ’s Manual Supplement”.
Retighten all fixing bolts of the towing
ball and bracket after approximately
1000 km (600 miles) of trailer driving.
PRETOWING SAFETY CHECK
Check that your vehicle remains level
when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle has
an abnormal nose −up or nose −down
condition, and check for improper
tongue load, overload, worn suspension
or other possible causes.
Make sure the trailer cargo is securely
loaded so that it cannot shift.
Check that your rear view mirrors con-
form to any applicable federal, state/
provincial or local regulations. If not,
install the rear view mirrors required
for towing purpose.

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To store the jack, turn the jack joint
until the jack base fits securely with
the vehicle body.
This prevents the jack from flying for-
ward during a collision or sudden
stop.To remove the wheel nut wrench, first
disengage the upper part of the
wrench from the holding bracket and
remove it.
When storing the wheel nut wrench,
make sure the wr ench is securely
held.To remove the spare tire:
1. Slide the front passenger ’s seat to the front −most lock position and
the right side second seat to the
rear −most lock position so they
will not interfere with the wheel nut
wrench.
Open the right side sliding door
and you will find the flap on the
floor. Pull back the flap to find the
spare tire clamp bolt.

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2. Loosen the spare tire clamp boltby turning it counterclockwise with
the wheel nut wrench.3. After the tire is lowered completelyto the ground, remove the holding
bracket.
When storing the spare tire, put it in
place with the outer side of the wheel
facing up. Then secure the tire, taking
care that the tire goes straight up
without catching on any other part, to
prevent it from flying forward during
a collision or sudden braking.
As the tire carrier is designed for the
compact spare tire, the standard tire
cannot be stored there.
CAUTION
Do not remove the spare tire
when jacking up the vehicle. The
tire carrier and the spare tire may
interfere with the jack and cause
a serious accident.
NOTICE
 To secure spare tire clamp
bolt:
Do not use impact wrench,
but wheel nut wrench.
 After taking out or stowing
the spare tire, make sure to
secure the tire carrier by
tightening the clamp bolt to
prevent the holding bracket
from hitting the under body
of the vehicle during driving.
 Do not store the flat spare
tire with the tire carrier so it
may not be held securely.

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To remove the jack, turn the jack joint
by hand until the jack becomes free.To store the jack, turn the jack joint
until the jack base fits securely with
the vehicle body.
This prevents the jack from flying for-
ward during a collision or sudden
stop.To remove the wheel nut wrench, first
disengage the upper part of the
wrench from the holding bracket and
remove it.
When storing the wheel nut wrench,
make sure the wr ench is securely
held.