2004 TOYOTA SIENNA brake sensor

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
The automatic light control sensor is on
the top of the driver’s side instrument
panel.
Do not place anything on the instrument
panel, and/or do not affix anything on the
windshield to block this sensor.
Automatic light cut off system
Position 1 or position 3 with the tail
lights on—
The lights automatically turn off when the
driver ’s door is opened with the ignition
key in the “ACC” or “LOCK” position.Position 2 or 3 with the headlights on—
The lights automatically turn off after 30
seconds when all the side doors and back
door are closed with the ignition key in
the “ACC” or “LOCK” position.
If the “
” (lock) switch of the wireless
remote control transmitter is pushed when
all the side doors and back door are al-
ready locked, the lights automatically turn
off immediately.
The time before the headlights turn off
can be changed. For details, contact your
Toyota dealer.
To turn them on again, turn the key to the
“ON” position or actuate the headlight
switch.
If you are going to park for over one
week, make sure the headlight switch is
off.
NOTICE
To prevent the battery from being dis-
charged, do not leave the lights on
for a long period when the engine is
not running.
Daytime Running Light (DRL) system
(all models sold in Canada and some
models sold in U.S.A.)
The Daytime Running Light (DRL) system
can make it easier for others to see the
front of your vehicle during the day. The
DRL system can be helpful in many differ-
ent driving conditions, but they can be
especially helpful in the short periods after
dawn and before sunset.
The DRL system will make the headlights
come on when:
The ignition is on with the engine run-
ning.
The knob is in the “OFF” position,
position 1 or position 3 with the tail
lights on.
The parking brake is released.
To turn off the DRL system, twist the knob
to position 2 or position 3 with the head-
lights on, or turn the ignition switch off.

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(a) Brake System Warning Light
This light comes on in the following cases
when the ignition key is in the “ON” posi-
tion.
When the parking brake is applied...
This light comes on for a few seconds
when the ignition key is turned to the
“ON” position even after the parking brake
is released.
When the brake fluid level is low...
CAUTION
It is dangerous to continue driving
normally when the brake fluid level is
low.
Have your vehicle checked at your
Toyota dealer in the following case:
The light does not come on even if the
parking brake is applied when the igni-
tion key is in the “ON” position.
The light does not come on even if the
ignition key is turned on with the park-
ing brake released.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If either of the following conditions
occurs, immediately stop your vehicle
at a safe place and contact your
Toyota dealer.
The light does not turn off even
after the parking brake is released
while the engine is running.
In this case, the brakes may not
work properly and your stopping
distance will become longer. De-
press the brake pedal firmly and
bring the vehicle to an immediate
stop.
The brake system warning light re-
mains on together with the “ABS”
warning light.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely un-
stable during braking.
(b) Driver’s Seat Belt Reminder Light and Buzzer
This light and buzzer remind you to
buckle up the driver’s seat belt.
Once the ignition key is turned to “ON”,
the reminder light flashes and buzzer
sounds if the driver ’s seat belt is not fas-
tened. Unless the driver fastens the belt,
the light keeps flashing and the buzzer
stops after about 4 to 8 seconds.
(c) Front Passenger ’s Seat Belt Re- minder Light
This light reminds you to buckle up the
front passenger ’s seat belt.
Once the ignition key is turned to “ON”,
the reminder light flashes if a passenger
sits in the front passenger seat and does
not fastened. However, if a front passen-
ger uses an additional seat cushion, the
light may not flash even when the seat
belt is not buckled up.
If luggage or other load is placed on the
front passenger seat, depending on its
weight and how it is placed on the seat,
built −in sensors in the seat cushion may
detect the pressure, causing the reminder
light to come on.

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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 works pr operly, the light turns off
after a few seconds. Thereafter, if the
system 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.
(i) Open Door Warning Light
This light remains on until all the doors
are completely closed.
(j) SRS Warning Light
This light will come on when the igni-
tion key is turned to the “ON” position.
After about 6 seconds, the light will go
off. This means the system of the air-
bag and front seat belt pretensioners
are operating properly.
The warning light system monitors the air-
bag sensor assembly, front airbag sen-
sors, side and curtain shield airbag sen-
sors, curtain shield airbag sensors,
driver ’s seat position sensor, driver ’s seat
belt buckle switch, front seat belt preten-
sioner assemblies, inflators, warning light,
interconnecting wiring and power sources.
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 or flashes while
driving.

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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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CAUTION
If the display flashes and beeps,
you must depress the brake pedal
to slow down to avoid a collision
or maintain sufficient vehicletove-
hicle distance.
In the following conditions, the ap-
proach warning may not turn on
even if the vehicle drives closer to
the vehicle ahead, and an accident
may occur:
Your vehicle and the vehicle ahead
are cruising at almost the same
speed.
The vehicle ahead is cruising at a
faster speed than yours. (The dis-
tance between the vehicles will be-
come longer.)
The vehicle ahead is at a stop or
driving very slowly. Pay special
attention to a very slow vehicle at
the end of the line in heavy traffic
or at a tollgate.
The speed has just been set.
The accelerator pedal is depressed
or has just been released.
LASER RADAR SENSOR
The laser radar sensor is used for ve-
hicletovehicle distance control cruis-
ing.
If dirt is on the sensor glass, the
dynamic laser cruise control function is
automatically cancelled and a warning
code appears on the display. (See
“VEHICLETOVEHICLE DISTANCE
CONTROL MODE FAILURE WARNING”
on page 206.)
However, if the glass sensor is covered
with icicle or any substance, dirt may
not be detected.Before driving in the vehicletovehicle
distance control mode, make sure the
radar sensor glass is clean.
This product is a class I laser product
complied with 21 C.F.R part 1040.10
and 1040.11.
CAUTION
To ensure that dynamic laser cruise
control will function properly while
driving, observe the following:
Always keep the laser radar sensor
glass clean. When cleaning, use a
soft cloth and be careful not to
damage the sensor.
Avoid strong impacts around the la-
ser radar sensor. An incorrect laser
radar sensor alignment will result in
system malfunction. A special de-
vice is required to adjust the laser
radar sensor alignment. Be sure to
have the sensor adjusted by your
Toyota dealer.
Do not affix a sticker (including a
transparent sticker) or attach an ac-
cessory around the laser radar sen-
sor.

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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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CAUTION
The Toyota park assist system is
intended as an aid to assist you to
park and is not a substitute for
your personal judgment. Make your
driving decisions based on your ob-
servations.
Do not attach accessories or other
objects to the vehicle within the
sensor perceptible area. Doing so
may cause the system to malfunc-
tion, which might result in an acci-
dent.
In certain situations, the system
will not function properly and when
the vehicle approaches certain ob-
jects, the system will not detect
those objects. Therefore, always ob-
serve the area around the vehicle
and do not rely solely on the sys-
tem.
For vehicles sold in Canada
This ISM device compiles with Cana-
dian ICES001.
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.

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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.