2004 TOYOTA SIENNA ABS

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This system operates by detecting pri-
marily the reflectors of the vehicle
ahead. The distance may not be accu-
rately or absolutely detected in the fol-
lowing cases:
The vehicle ahead has higher ground
clearance, which means that the
placement of the reflectors is in a
higher position.
The rear section of the vehicle ahead
is extremely dirty.
The vehicle ahead or other vehicles
around you are flinging up water or
snow.
Excessive exhaust gas (black smoke)
is coming from the vehicle ahead or
other vehicles around you, obscuring
your front view.
There is an obstruction (protective
film, sticker, etc.) on the reflectors
on the vehicle ahead, or reflectors
are not installed on the vehicle
ahead or are damaged.
Heavy luggage in the luggage
compartment or rear seats is caus-
ing the nose of your vehicle to tilt
up.
CAUTION
To avoid accidents, always keep the
laser radar sensor glass clean and
never allow it to be covered with
icicle or any substance, so it can de-
tect the vehicle in front. (See “LASER
RADAR SENSOR” on page 205.)
CAUTION
Do not rely excessively on dynamic
laser cruise control. Observe the fol-
lowing precautions in order to avoid
serious injury or death:
Under certain conditions where the
vehicle in front slows drastically, or
is stopped, the dynamic laser cruise
control will neither warn you nor
decelerate. You must depress the
brake pedal to slow down, ensuring
collision avoidance or that suffi-
cient vehicletovehicle distance is
maintained.
Do not use dynamic laser cruise
control in the following conditions:
In bad weather (such as rain, fog,
snow, sandstorms or direct sun-
light, or when raindrops or snow-
flakes get on the laser radar sensor
glass), the vehicletovehicle dis-
tance will not be measured accura-
tely.
When using the windshield wipers
at high or low speeds the dynamic
laser radar cruise control turns off.

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In the following cases, the system may
not work properly.
When ice, snow, mud or other objects
build up on the sensor.
When the vehicle is parked in extreme-
ly high or extremely low temperature
for a long period.
When driving on bumpy or graveled
roads or on grass
When a device such as a horn from
another vehicle, motorcycle engine, or
an air brake sound from a heavy −duty
vehicle, issues ultrasonic waves, near
your vehicle
When attaching a two −way radio anten-
na
When rain or water splashes on the
sensor.
When operating the vehicle on an in-
clined surface
When a radio antenna or fender pole
is mounted on your vehicle.
When a towing hitch is mounted on
your vehicle. The system may not detect the follow-
ing.
Thin objects such as a wire or rope
Objects with a surface area too small
to reflect ultrasonic waves such as
wire gauze
Sound wave absorbing objects or mate-
rial such as cotton or snow
A person near the vehicle (depending
on the type of clothes worn)
Objects with a sharp edge
Small or short objects
Tall objects with an upper part project-
ing toward the vehicle
Objects just under the bumper
Objects very close to your vehicle
In the following cases, have your
Toyota dealer check the system.
When the bumper is damaged.
When the indicator is continuously on.
1: Rear sensors
2: Rear corner sensors
The Toyota park assist system is de-
signed to inform you of the approxi-
mate distance between your vehicle and
an obstruction by indicator and buzzer
while driving at approximate 10 km/h (6
mph) or less when parking the vehicle.
This system uses sensors to detect ob-
structions.
This system works when the ignition key
is at the “ON” position and the transmis-
sion is in the “R” position.
The sensors work only when the transmis-
sion is in the “R” position.
Toyota park assist system
(type B)

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The system may not detect the follow-
ing.
Thin objects such as a wire or rope
Objects with a surface area too small
to reflect ultrasonic waves such as
wire gauze
Sound wave absorbing objects or mate-
rial such as cotton or snow
A person near the vehicle (depending
on the type of clothes worn)
Objects with a sharp edge
Small or short objects
Tall objects with an upper part project-
ing toward the vehicle
Objects just under the bumper
Objects very close to your vehicle
In the following cases, have your
Toyota dealer check the system.
When the bumper is damaged.
When the indicator is continuously on. The rear view monitor system assists
the driver by displaying an image of
the rear of the vehicle while backing
up. The displayed image on the screen
is a horizontally reversed mirror image
of the inside rear view mirror.
To display the rear view image on the
screen, place the selector lever in the
“R” position when the ignition switch
in the “ON” position.
If you move the selector lever out of the
“R” position, the screen returns to the
previous screen. Operating another func-
tion of the navigation system will display
another screen.
The rear view monitor system is a supple-
ment device intended to assist back up.
When backing up, be sure to check be-
hind and all around the vehicle visually.
CAUTION
Never depend on the rear view
monitor system entirely when back-
ing up. Always make sure your in-
tended oath is clear.
Use caution just as you would when
backing up any vehicle.
Never back up while looking only at
the screen. The image on the
screen is different from actual con-
ditions. Depicted distances between
objects and flat surfaces will differ
from actual distances. If you back
up while looking only at the screen,
you may hit a vehicle, a person or
an object. When backing up, be
sure to check behind and all around
the vehicle visually and with mir-
rors before proceeding.
Do not use the system when the
back door is not completely closed.
Rear view monitor system

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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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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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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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Weight carrying hitchWithout towing package 90 kg (200 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.
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.

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Because stopping distance may be in-
creased, vehicle−to −vehicle distance
should be increased when towing a
trailer. For each 16 km/h (10 mph) of
speed, allow at least one vehicle and
trailer length between you and the ve-
hicle ahead. Avoid sudden braking as
you may skid, resulting in jackknifing
and loss of control. This is especially
true on wet or slippery surfaces.
Avoid jerky starts or sudden accelera-
tion.
Avoid jerky steering and sharp turns.
The trailer could hit your vehicle in a
tight turn. Slow down before making a
turn to avoid the necessity of sudden
braking.
Remember that when making a turn,
the trailer wheels will be closer than
the vehicle wheels to the inside of the
turn. Therefore, compensate for this by
making a larger than normal turning
radius with your vehicle.
Crosswinds and rough roads will ad-
versely affect handling of your vehicle
and trailer, causing sway. Pay attention
to the rear from time to time to pre-
pare yourself for being passed by large
trucks or buses, which may cause your
vehicle and trailer to sway. If swaying
happens, firmly grip the steering wheel
and reduce speed immediately but
gradually. Never increase speed. Steer
straight ahead. If you make no extreme
correction with the steering or brakes,
the vehicle and trailer will stabilize.
Be careful when passing other ve-
hicles. Passing requires considerable
distance. After passing a vehicle, do
not forget the length of your trailer and
be sure you have plenty of room be-
fore changing lanes.
In order to maintain engine braking effi-
ciency, do not place the transmission
in “D”.
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30 C [85 F]) when going up a long or
steep grade with a trailer. If the engine
coolant temperature gauge indicates
overheating, immediately turn off the air
conditioning (if in use), pull off the road
and stop in a safe spot. Refer to “If
your vehicle overheats” on page 410 in
Section 4.
Always place wheel blocks under both
the vehicle and trailer wheels when
parking. Apply the parking brake firmly.
Put the transmission in “P”. Avoid park-
ing on a slope with a trailer, but if it
cannot be avoided, do so only after
performing the following:
1. Apply the brakes and hold.
2. Have someone place wheel blocks un- der both the vehicle and trailer wheels.
3. When the wheel blocks are in place, release your brakes slowly until the
blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into “P” and turn off the engine.