2004 TOYOTA SIENNA wheel

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
On roads with heavy traffic or
sharp bends, an appropriate speed
cannot be maintained and an acci-
dent may occur.
On slippery road surfaces (icy or
snowcovered road surfaces), the
tires will race and you will be un-
able to control the vehicle.
When there is no vehicle detected
ahead on steep downhill slopes, the
preset speed will be easily exceed-
ed because of inefficient engine
braking. (In this case, automatic
braking will not work.) If there is a
vehicle detected ahead, the delay in
deceleration timing could cause se-
rious injury or death.
When the alarm sounds frequently
(because acceleration or decelera-
tion was repeated or sufficient ve-
hicletovehicle distance was not
maintained), an appropriate vehicle
speed cannot be attained and an
accident may occur.On roads with steep and short in-
clines and declines, failure to de-
tect the vehicle ahead will shorten
the distance between your vehicle
and the vehicle ahead and an acci-
dent may occur.
Deceleration cruising function and
approach warning do not operate
when the vehicle ahead is at a stop
or driving very slowly.
If the vehicle ahead of you deceler-
ates abruptly or if another vehicle
cuts in ahead of you, your vehicle
may collide with the vehicle ahead
unless you manually depress the
brake pedal to slow down your ve-
hicle.
Depending on the road configura-
tion (curved, left and right continu-
ous curved, the start or end of a
curve, or narrow driving lanes due
to road construction) or your ve-
hicle condition (steering wheel ma-
neuvering, position in the lane, or
unstable driving because of an acci-
dent or breakdown), vehicles in oth-
er lanes or surrounding objects
may be detected, resulting in a con-
trol failure or the approach warning
activation. This may also result in
a very close distance between vehi-
cles due to a failure to detect the
vehicle ahead.

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Some parts of the audio system can be
adjusted using the switches on the steer-
ing wheel.
Details of the specific switches, controls,
and features are described below.1. Volume control switch
2. “ ” switch
3. “MODE” switch
Audio remote controls (steering switches)

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
The tandem master cylinder brake system
is a hydraulic system with two separate
sub−systems. If either sub −system s hould
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping distance will increase. Also, the
brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a
single brake system. Have your
brakes fixed immediately.
BRAKE BOOSTER
The brake booster uses engine vacuum to
power −assist the brakes. If the engine
should quit while you are driving, you can
bring the vehicle to a stop with normal
pedal pressure. There is enough reserved
vacuum for one or two stops—but no
more!
CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your reserved vacu-
um.
Even if the power assist is com-
pletely lost, the brakes will still
work. But you will have to push the
pedal hard, much harder than nor-
mal. And your braking distance will
increase.
ANTILOCK BRAKE SYSTEM (with
“ABS” warning light)
The antilock brake system is designed
to help prevent lockup of the wheels
during a sudden braking or braking on
slippery road surfaces. This assists in
providing directional stability and steer-
ing performance of the vehicle under
these circumstances.
Effective way to press the ABS brake
pedal: When the anti −lock brake system
function is in action, you may feel the
brake pedal pulsating and hear a noise.
In this situation, to let the anti −lock
brake system work for you, just hold the
brake pedal down more firmly. Do not
pump the brake in a panic stop. This
will result in reduced braking performan-
ce.
The anti −lock brake system becomes op-
erative after the vehicle has accelerated
to a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery
road surfaces such as on a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the anti −lock brake sys-
tem.
You may hear a click or motor sound in
the engine compartment for a few seconds
when the engine is started or just after
the vehicle begins to move. This means
that the anti −lock brake system is in the
self −check mode, and does not indicate a
malfunction.
Brake system

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
When the antilock brake system is ac-
tivated, the following conditions may
occur. They do not indicate a malfunc-
tion of the system:
You may hear the anti−lock brake sys-
tem operating and feel the brake pedal
pulsating and the vibrations of the ve-
hicle body and steering wheel. You
may also hear the motor sound in the
engine compartment even after the ve-
hicle is stopped.
At the end of the anti −lock brake sys-
tem activation, the brake pedal may
move a little forward.
CAUTION
Do not overestimate the antilock
brake system: Although the antilock
brake system assists in providing ve-
hicle control, it is still important to
drive with all due care and maintain
a moderate speed and safe distance
from the vehicle in front of you, be-
cause there are limits to the vehicle
stability and effectiveness of steering
wheel operation even with the anti
lock brake system on.
If tires grip performance exceeds its
capability, or if hydroplaning occurs
during high speed driving in the rain,
the antilock brake system does not
provide vehicle control.
Antilock brake system is not de-
signed to shorten the stopping dis-
tance: Always drive at the moderate
speed and maintain a safe distance
from the vehicle in front of you.
Compared with vehicles without an
antilock brake system, your vehicle
may require a longer stopping dis-
tance in the following cases:
Driving on rough, gravel or snow
covered roads.
Driving with tire chains installed.
Driving over the steps such as the
joints on the road.
Driving on roads where the road
surface is pitted or has other differ-
ences in surface height.
Install all 4 tires of specified size at
appropriate pressure: The antilock
brake system detects vehicle speeds
using the speed sensors for respec-
tive wheels’ turning speeds. The use
of tires other than specified may fail
to detect the accurate turning speed
resulting in a longer stopping dis-
tance.

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Ty p e A
Ty p e B
“ABS” warning light
Vehicles without the vehicle stability
control system—
The light comes on when the ignition key
is turned to the “ON” position. If the anti−
lock brake system works properly, the
light turns off after a few seconds. There-
after, if either of the systems malfunc-
tions, the light comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate,
but the brake system still operates con-
ventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
but the brake assist system still operates.
In this case the wheels could lock up
during a sudden braking or braking on
slippery road surfaces. If either of the following conditions
occurs, this indicates a malfunction
somewhere in the components moni-
tored by the warning light system. Con-
tact your Toyota dealer as soon as
possible to service the vehicle.
The light does not come on when the
ignition key is turned to the “ON” posi-
tion, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Vehicles with the vehicle stability con-
trol system—
The light comes on when the ignition key
is turned to the “ON” position. If the anti−
lock brake system and the brake assist
system work properly, the light turns off
after a few seconds. Thereafter, if either
of the systems malfunctions, the light
comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system, the brake assist
system, the traction control system and
the vehicle stability control system do not
operate, but the brake system still oper-
ates conventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
so that the wheels could lock up during
a sudden braking or braking on slippery
road surfaces. If either of the following conditions
occurs, this indicates a malfunction
somewhere in the parts monitored by
the warning light system. Contact your
Toyota dealer as soon as possible to
service the vehicle.
The light does not come on when the
ignition key is turned to the “ON” posi-
tion, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
BRAKE ASSIST SYSTEM
When you slam the brakes on, the
brake assist system judges as an emer-
gency stop and provides more powerful
braking for a driver who cannot hold
down the brake pedal firmly.
When you slam the brakes on, more pow-
erful braking will be applied. At this time,
you may hear a sound in the engine
compartment and feel the vibrations of the
brake pedal. This does not indicate a mal-
function.
Vehicles with the vehicle stability control
system—
The brake assist system becomes opera-
tive after the vehicle has accelerated to
a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
For an explanation of this system’s warn-
ing light, see “Service reminder indicators
and warning buzzers” on page 167 in Sec-
tion 1 −5.

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
This illustration indicates typical tire
size.1. Tire use (P=Passenger car, T=Temporary use)
2. Section width (in millimeters)
3. Aspect ratio (tire height to section width)
4. Tire construction code (R=Radial, D=Diagonal)
5. Wheel diameter (in inches)
6. Load index (2 digits or 3 digits)
7. Speed symbol (alphabet with one letter)1. Section width
2. Tire height
3. Wheel diameter1. Bead
2. Sidewall
3. Shoulder
4. Tread
5. Belt
6. Inner liner
7. Reinforcing rubber
8. Carcass
9. Rim lines
10.Bead wires
11. Chafer
—Tire size —Name of each section of tire

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Temperature A, B, C—T he tem per a-
ture grades are A (the highest), B,
and C, representing the tire’s resis-
tance to the generation of heat and
its ability to dissipate heat when
tested under controlled conditions on
a specified indoor laboratory test
wheel. Sustained high temperature
can cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. The grade C cor-
responds to a level of performance
which all passenger car tires must
meet under the Federal Motor Vehicle
Safety Standard No.109. Grades B
and A represent higher levels of per-
formance on the laboratory test wheel
than the minimum required by law.
Warning: The temperature grades for
this tire are established for a tire that
is properly inflated and not over-
loaded. Excessive speed, underinfla-
tion, or excessive loading, either sep-
arately or in combination, can cause
heat buildup and possible tire failure.