2003 TOYOTA TUNDRA Sensors

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
The driver and front passenger ’s seat
belt pretensioners are designed to be
activated in response to a severe fron-
tal impact.
When the airbag sensor detects the shock
of a severe frontal impact, the front seat
belts are quickly drawn back in by the
retractors so that the belts snugly restrain
the front seat occupants.
The front seat belt pretensioners are acti-
vated even with no passenger in the front
seat.
Collisions occurring at certain s peeds and
angles may cause the seat belt preten-
sioners and SRS airbags not to operate
all together.This indicator comes on when the igni-
tion key is turned to the “ON” position.
It goes off after about 6 seconds. This
means the front seat belt pretensioners
are operating properly.
This warning light system monitors the
airbag sensor assembly, front airbag sen-
sors, seat belt pretensioner assemblies,
inflators, warning light, interconnecting wir-
ing and power sources. (For details, see
“Service reminder indicators and warning
buzzers” in Section 1 −5.)The front seat belt pretensioner system
mainly consists of the following compo-
nents and their locations are shown in the
illustration.
1. Front airbag sensors
2. SRS warning light
3. Front seat belt pretensioner assemblies
4. Airbag sensor assembly
The front seat belt pretensioners are con-
trolled by the airbag sensor assembly. The
airbag sensor assembly consists of a saf-
ing sensor and airbag sensor.
—Front seat belt
pretensioners

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
The SRS airbag system mainly consists of
the following components, and their loca-
tions are shown in the illustration.
1. Front airbag sensors
2. SRS warning light
3. Airbag module for right front passenger (airbag and inflator)
4. Passenger airbag manual on −off switch
5. Airbag sensor assembly
6. Airbag module for driver (airbag and inflator)
The airbag sensor assembly consists of a
safing sensor and airbag sensor. The airbag sensors constantly monitor the
forward deceleration of the vehicle. If an
impact results in a forward deceleration
beyond the designed threshold level, the
system triggers the airbag inflators. At this
time a chemical reaction in the inflators
very quickly fills the airbags with non
−tox-
ic gas to help restrain the forward motion
of the occupants. The airbags then quickly
deflate, so that there is no obstruction of
the driver ’s vision should it be necessary
to continue driving.
When the airbags inflate, they produce a
loud noise and release some smoke and
residue along with non −toxic gas. This
does not indicate a fire. This smoke may
remain inside the vehicle for some time,
and may cause some minor irritation to
the eyes, skin or breathing. Be sure to
wash off any residue as soon as possible
to prevent any potential skin irritation with
soap and water. If you can physically and
safely exit the vehicle after a collision,
you should do so at the first opportunity. Deployment of the airbags happens in a
fraction of a second, so the airbags must
inflate with considerable force. While the
system is designed to r
educe serious inju-
ries, primarily to the head and chest, it
may also cause other, less severe injuries
to the face, chest, arms and hands. These
are usually in the nature of minor burns
or abrasions and swelling, but the force of
a deploying airbag can cause more seri-
ous injuries, especially if an occupant’s
hands, arms, chest or head are in close
proximity to the airbag module at the time
of deployment. This is why it is important
for the occupant to: avoid placing any
object or part of the body between the
occupant and the airbag module; sit
straight and well back into the seat; wear
the available seat belt properly; and sit as
far as possible from the airbag module,
while still maintaining control of the ve-
hicle.
Parts of the airbag module (steering wheel
hub, airbag cover and inflator) may be hot
for several minutes after deployment, so
do not touch! The airbags inflate only
once. The windshield may be damaged by
absorbing some of the force of the inflat-
ing airbag.

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
(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...
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.
CAUTION
If the light does not turn off even
after the parking brake is released
while the engine is running, immedi-
ately stop your vehicle at a safe
place and contact your Toyota dealer.
In this case, the brakes may not work
properly and your stopping distance
will become longer. Depress the brake
pedal firmly and bring the vehicle to
an immediate stop.
(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” or
“START”, the reminder light flashes and
buzzer sounds if the driver ’s seat belt is
not fastened. 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” or
“START”, the reminder light flashes if a
passenger sits in the front passenger seat
and does not fasten the seat belt. Howev-
er, if a front passenger 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 keep flashing.
(d) Discharge Warning Light
This light warns that the battery is being
discharged.
If it comes on while you are driving, there
is a problem somewhere in the charging
system.
The engine ignition will continue to oper-
ate, however, until the battery is dis-
charged. Turn off the air conditioning,
blower, radio, etc., and drive directly to
the nearest Toyota dealer or repair shop.

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
Antilock brake system is not de-
signed to shorten the stopping dis-
tance: Always drive at a 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.
Ty p e A
Ty p e B
“ABS” Warning light
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 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 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
so that the wheels could lock up during
a sudden braking or braking on slippery
road surfaces.
If either of the following conditions oc-
curs, this indicates a malfunction some-
where in the components 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.