1999 TOYOTA SIENNA suspension

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65
The seat belt pretensioner system mainly
consists of the following components and
their locations are shown in the illustra-
tion.
1. Front airbag sensors
2. SRS airbag warning light
3. Seat belt pretensioner assemblies
4. Airbag sensor assembly
The seat belt pretensioner is controlled by
the airbag sensor assembly. The airbag
sensor assembly consists of a safing sen-
sor and airbag sensor.When a seat belt pretensioner is acti-
vated, an operating noise may be heard
and a small amount of smoke−like gas
may be released. This gas is harmless
and does not indicate that a fire is occur-
ring.
Once the seat belt pretensioner has been
activated, the seat belt retractor remains
locked.
CAUTION
Do not modify, remove, strike or open
the front seat belt pretensioner as-
semblies, airbag sensor or surround-
ing area or wiring. Doing any of
these may cause sudden operation of
the front seat belt pretensioners or
disable the system, which could re-
sult in death or serious personal inju-
ry.
Failure to follow these instructions
can result in death or serious inju-
ries.
NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can
interfere with proper operation of the
seat belt pretensioners in some
cases.
Installation of electronic items such
as a mobile two−way radio, cassette
tape player or compact disc player
Repairs on or near the front seat
belt pretensioner assemblies
Modification of the suspension sys-
tem
Modification of the front end struc-
ture
Attachment of a grille guard (bull
bar, kangaroo bar, etc.), snowplow,
winches or any other equipment to
the front end
Repairs made on or near the front
fenders, front end structure or con-
sole
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Do not put objects or your pets on
or in front of the dashboard or
steering wheel pad that houses the
airbag system. They might restrict
inflation or cause death or serious
injury as they are projected rear-
ward by the force of the deploying
airbags. Likewise, the driver and
front passenger should not hold
things in their arms or on their
knees.
Do not modify or remove any wir-
ing. Do not modify, remove, strike
or open any components such as
the steering wheel pad, steering
wheel, column cover, front passen-
ger airbag cover, front passenger
airbag or airbag sensor assembly.
Doing any of these may cause sud-
den SRS airbag inflation or disable
the system, which could result in
death or serious injury.
Failure to follow these instructions
can result in death or serious inju-
ries.NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can
interfere with proper operation of the
SRS airbag system in some cases.
Installation of electronic items such
as a mobile two−way radio, cassette
tape player or compact disc player
Modification of the suspension sys-
tem
Modification of the front end struc-
ture
Attachment of a grille guard (bull
bar, kangaroo bar, etc.), snowplow,
winches or any other equipment to
the front end
Repairs made on or near the front
fenders, front end structure, con-
sole, steering column, steering
wheel or dashboard near the front
passenger airbag
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Part 2
INFORMATION
BEFORE DRIVING
YOUR TOYOTA
Break−in period
Fuel
Operation in foreign countries
Three−way catalytic converter
Engine exhaust cautions
Facts about engine oil
consumption
Twin ground electrode
platinum−tipped spark plugs
Brake system
Brake pad wear limit indicators
Luggage stowage precautions
Roof luggage carrier
Your Toyota’s identification
Theft prevention labels
Suspension and chassis
Types of tires
Break−in period
Drive gently and avoid high speeds.
Your vehicle does not need an elaborate
break−in. But following a few simple tips
for the first 1600 km (1000 miles) can add
to the future economy and long life of
your vehicle:
Do not drive over 88 km/h (55 mph).
Run the engine at moderate speed be-
tween 2000 and 4000 rpm.
Avoid full−throttle starts.
Try to avoid hard stops during the first
300 km (200 miles).
Do not drive for a long time at any
single speed, either fast or slow.
Do not tow a trailer during the first 800
km (500 miles).
Fuel
FUEL TYPE
Your new vehicle must use only un-
leaded gasoline.
To help prevent gas station mix−ups, your
Toyota has a new smaller fuel tank open-
ing. The special nozzle on pumps with
unleaded fuel will fit it, but the larger
standard nozzle on pumps with leaded gas
will not.
At a minimum, the gasoline you use
should meet the specifications of ASTM
D4814 in the U.S.A. and CGSB 3.5−M93
in Canada.
NOTICE
Do not use leaded gasoline. Use of
leaded gasoline will cause the three−
way catalytic converter to lose its ef-
fectiveness and the emission control
system to function improperly. Also,
this can increase maintenance costs.
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Your new vehicle carries theft preven-
tion labels which are approximately 56
mm (2.20 in.) by 16 mm (0.63 in.).
The purpose of these labels is to reduce
the incidence of vehicle thefts by facilitat-
ing the tracing and recovery of parts from
stolen vehicles. The label is designed so
that once it is applied to a surface, any
attempt to remove it will result in destroy-
ing the integrity of the label. Transferring
these labels intact from one part to anoth-
er, will be impossible.
NOTICE
You should not attempt to remove the
theft prevention labels as it may vio-
late certain state or federal laws.
Suspension and chassis
CAUTION
Do not modify the suspension/chassis
with lift kits, spacers, springs, etc. It
can cause dangerous vehicle handling
characteristics, resulting in loss of
control.
Types of tires
Determine what kind of tires your ve-
hicle is originally equipped with.
1. Summer tires
Summer tires are high−speed capability
tires best suited to highway driving under
dry conditions.
Since summer tires do not have the same
traction performance as snow tires, sum-
mer tires are inadequate for driving on
snow−covered or icy roads. For driving on
snow−covered or icy roads, we recom-
mend using snow tires. If installing snow
tires, be sure to replace all four tires.
2. All season tires
All season tires are designed to provide
better traction in snow and to be adequate
for driving in most winter conditions, as
well as for use all year round.
All season tires, however, do not have
adequate traction performance compared
with snow tires in heavy or loose snow.
Also, all season tires fall short in accel-
eration and handling performance
compared with summer tires in highway
driving.
Theft prevention labels
(except for Canada)
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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. Adjust the tire pres-
sure to the recommended cold tire
pressure indicated below (see Chapter
7−2 for instructions.):
Tire pressure, kPa (kgf/cm
2 or bar, psi)
240 (2.4, 35)
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.BREAK−IN 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 informa-
tion, please refer to the scheduled
maintenance information in the ”Sched-
uled 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.
PRE−TOWING 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.
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IN THE ENGINE COMPARTMENT
Items listed below should be checked
from time to time, e.g. each time when
refueling.
Washer fluid
Make sure there is sufficient fluid in the
tank. See Chapter 7−3 for additional in-
formation.
Engine coolant level
Make sure the coolant level is between
the ”FULL” and ”LOW” lines on the see−
through reservoir when the engine is cold.
See Chapter 7−2 for additional information.
Battery electrolyte level
Make sure the electrolyte level of all bat-
tery cells is between upper and lower lev-
el lines on the case. Add only distilled
water when replenishing. See Chapter 7−3
for additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See Chapter 7−2 for additional information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See Chapter 7−2 for addi-
tional information.Power steering fluid level
Check the level through the reservoir. The
level should be in the ”HOT” or ”COLD”
range depending on the fluid temperature.
See Chapter 7−2 for additional information.
Exhaust system
If you notice any change in the sound of
the exhaust or smell exhaust fumes, have
the cause located and corrected immedi-
ately. (See engine exhaust cautions in
Part 2.)Be on the alert for changes in perfor-
mance, sounds, and visual tip−offs that
indicate service is needed. Some impor-
tant clues are as follows:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A leak under the vehicle (however, wa-
ter dripping from the air conditioning
after use is normal.)
Change in exhaust sound (This may
indicate a dangerous carbon monoxide
leak. Drive with the windows open and
have the exhaust system checked im-
mediately.)
Flat−looking tire; excessive tire squeal
when cornering; uneven tire wear
Vehicle pulls to one side when driving
straight on a level road
Strange noises related to suspension
movement
Loss of brake effectiveness; spongy
feeling brake pedal; pedal almost
touches floor; vehicle pulls to one side
when braking
Engine coolant temperature continually
higher than normal
Does your vehicle need
repairing?
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