2003 CHEVROLET SILVERADO sensor

Seat Position Sensors
Vehicle's with dual stage air bags are also equipped
with special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensor provides
information which is used to determine if the air bags
should deploy at a reduced level or at full deployment.
Single Stage Air Bags
If your vehicle has frontal air bags with single stage
deployment and your vehicle goes straight into a wall
that does not move or deform, the threshold level
is about 13 to 16 mph (20 to 25 km/h). The threshold
level can vary, however, with speci®c vehicle design, so
that it can be somewhat above or below this range.
If your vehicle strikes something that will move or
deform, such as a parked car, the threshold level will be
higher. The air bag is not designed to in¯ate in
rollovers, rear impacts, or in many side impacts because
in¯ation would not help the occupant.
What Makes an Air Bag In¯ate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. The
sensing system triggers a release of gas from the
in¯ator, which in¯ates the air bag. The in¯ator, air bag,
and related hardware are all part of the air bag
modules inside the steering wheel and in the instrument
panel in front of the right front passenger.
How Does an Air Bag Restrain?
In moderate to severe frontal or near-frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. Air bags supplement the
protection provided by safety belts. Air bags distribute
the force of the impact more evenly over the occupant's
upper body, stopping the occupant more gradually.
But air bags would not help you in many types of
collisions, including rollovers, rear impacts and many
side impacts, primarily because an occupant's motion is
not toward those air bags. Air bags should never be
regarded as anything more than a supplement to safety
belts, and then only in moderate to severe frontal or
near-frontal collisions.
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·Your vehicle is equipped with electronic frontal
sensors which help the sensing system distinguish
between a moderate and a more severe frontal
impact. Your vehicle is also equipped with a crash
sensing and diagnostic module, which records
information about the frontal air bag system. The
module records information about the readiness of
the system and when the system commands air bag
in¯ation. It records the status of the driver's safety
belt usage in a crash in which the air bag deploys or
a crash in which the air bag nearly deploys. The
module also records speed, engine rpm, brake and
throttle data.
·Let only quali®ed technicians work on your air bag
systems. Improper service can mean that an air bag
system will not work properly. See your dealer for
service.
Notice:If you damage the covering for the driver's
or the right front passenger's air bag, the bag
may not work properly. You may have to replace the
air bag module in the steering wheel or both the
air bag module and the instrument panel for
the right front passenger's air bag. Do not open or
break the air bag coverings.
Air Bag Off Switch
Regular Cab and Extended Cab Models
If your vehicle is a regular cab model or an extended cab
model, it has a switch on the instrument panel that you
can use to turn off the right front passenger's air bag.
United States with Passenger Sensing System
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To turn the right front passenger's air bag on again,
insert your ignition key into the switch, push in,
and move the switch to the ON or AUTO position.
Passenger Sensing System
If your rearview mirror has one of the indicators pictured
in the following illustrations, your vehicle has a passenger
sensing system. The indicator will be visible when you
turn your ignition key to RUN or START. The words ON
and OFF or the symbol for on and off, will be visible on
the rearview mirror during the system check. When the
system check is complete, either the word ON or the word
OFF, or the symbol for on or the symbol for off will be
visible. See
Passenger Air Bag Status Indicator on
page 3-40. If your rearview mirror does not have either of
the indicators pictured below, then your vehicle does not
have the passenger sensing system.The passenger sensing system will turn off the right
front passenger's frontal air bag under certain
conditions. The driver's air bag and the side air bags
are not part of the passenger sensing system. In
addition to the passenger sensing system, your vehicle
also has an air bag off switch located on the instrument
panel as required by the government.
The passenger sensing system works with sensors that
are part of the right front passenger's seat and safety
belt. The sensors are designed to detect the presence of
a properly seated occupant and determine if the
passenger's frontal air bag should be enabled (may
in¯ate) or not.
Passenger Air Bag Status Indicator ± United States
Passenger
Air Bag Status
Indicator-Canada
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Servicing Your Air Bag-Equipped
Vehicle
Air bags affect how your vehicle should be serviced.
There are parts of the air bag system in several places
around your vehicle. You don't want the system to
in¯ate while someone is working on your vehicle. Your
dealer and the service manual have information
about servicing your vehicle and the air bag system. To
purchase a service manual, see
Service Publications
Ordering Information on page 7-9.
{CAUTION:
For up to 1 minute after the ignition key is
turned off and the battery is disconnected, an
air bag can still in¯ate during improper
service. You can be injured if you are close to
an air bag when it in¯ates. Avoid yellow
connectors. They are probably part of the air
bag system. Be sure to follow proper service
procedures, and make sure the person
performing work for you is quali®ed to do so.
The air bag system does not need regular maintenance.
Adding Equipment to Your Air
Bag-Equipped Vehicle
Q:Is there anything I might add to the front of the
vehicle that could keep the air bags from
working properly?
A:Yes. If you add things that change your vehicle's
frame, bumper system, front end sheet metal or
height, they may keep the air bag system
from working properly. Also, the air bag system
may not work properly if you relocate any of the air
bag sensors. If you have any questions about
this, you should contact Customer Assistance
before you modify your vehicle. The phone
numbers and addresses for Customer Assistance
are in Step Two of the Customer Satisfaction
Procedure in this manual. See²Customer
Satisfaction Procedure²in the Index.
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Automatic Headlamp System
When it is dark enough outside, your automatic headlamp
system will turn on your headlamps at the normal
brightness along with other lamps such as the taillamps,
sidemarker, parking lamps and the instrument panel
lights. The radio lights will also be dim.
Your vehicle is equipped with a light sensor located on
the top of the instrument panel in the defroster grille. Be
sure it is not covered, or the system will be on whenever
the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast weather
or a tunnel. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running Lamps
(DRL) and the automatic headlamp systems so that
driving under bridges or bright overhead street lights does
not affect the system. The DRL and automatic headlamp
system will only be affected when the light sensor sees a
change in lighting lasting longer than the delay.
If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once you
leave the garage, it will take approximately one minute for
the automatic headlamp system to change to DRL if it is
bright enough outside. During that delay, your instrument
panel cluster may not be as bright as usual. Make sureyour instrument panel brightness control is in the full
bright position. See ªInstrument Panel Brightness
Controlº underInterior Lamps on page 3-18.
To idle your vehicle with the automatic headlamp system
off, turn the control to the off position.
You may be able to turn off your automatic headlamp
system. See
Daytime Running Lamps (DRL)later in this
section for more information.
You may be able to turn off your Automatic Headlamp
System. See ªDaytime Running Lamps (DRL)º later in
this section for more information.
As with any vehicle, you should turn on the regular
headlamp system when you need them.
Lamps On Reminder
A reminder chime will sound when your headlamps or
parking lamps are manually turned on and your
ignition is off, in LOCK, ACCESSORY, or your door is
open. To disable the chime, turn the light off then
back on.
Daytime Running Lamps
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day. DRL
can be helpful in many different driving conditions, but
they can be especially helpful in the short periods after
dawn and before sunset. Fully functional daytime running
lamps are required on all vehicles ®rst sold in Canada.
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The DRL system will come on when the following
conditions are met:
·the ignition is on,
·the exterior lamps control is in AUTO,
·the automatic transmission is not in PARK (P), and
·the light sensor determines it is daytime.
When the DRL are on, only your DRL lamps will be on.
The taillamps, sidemarker and other lamps won't be
on. The instrument panel won't be lit up either.
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps or the last
chosen headlamp setting that was used.
When you turn the headlamp switch off, the headlamps
will go off, and your DRL lamps will illuminate,
provided it is not dark outside.
To idle an automatic transmission equipped vehicle with
the DRL off, set the parking brake. Shifting the
transmission into PARK (P) will also allow you to idle
the vehicle with the DRL off. The DRL will stay off until
you release the parking brake or shift the transmission
out of PARK (P).
To idle a manual transmission equipped vehicle with the
DRL off, set the parking brake. The DRL will stay off
until you release the parking brake.
Fog Lamps
If your vehicle has fog lamps, use them for better vision
in foggy or misty conditions.
The fog lamp button is
located on the left side of
your instrument panel.
Your parking lamps and/or low-beam headlamps must
be on for your fog lamps to work.
Press the button to turn the fog lamps on. Press the
button again to turn them off. An indicator light will glow
in the button when the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use the fog lamps in the
dark without turning on the headlamps.
The fog lamps will go off whenever the high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
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If the driver and passenger's temperature settings
are not the same, the opposite side temperature
setting will be displayed for an additional ®ve
seconds. To make the passenger's temperature the
same as the driver's press and hold the AUTO
button for about four seconds.
When auto is selected, the air conditioning operation
and air inlet will be automatically controlled. The
air conditioning compressor will run when the
outside temperature is over about 40ÉF (4ÉC). The
air inlet will normally be set to outside air. If it's
hot outside, the air inlet may automatically switch to
recirculate inside air to help quickly cool down
your vehicle. The light on the button will illuminate
in recirculation.
2. Set the driver's and passenger's temperature.
To ®nd your comfort setting, start with a 74ÉF (23ÉC)
temperature setting and allow about 20 minutes
for the system to regulate. Turn the driver's or
passenger's side temperature knob to adjust the
temperature setting as necessary. If you choose the
temperature setting of 60ÉF (15ÉC) the system
will remain at the maximum cooling setting. If you
choose the temperature setting of 90ÉF (32ÉC)
the system will remain at the maximum heat setting.
Choosing either maximum setting will not cause
the vehicle to heat or cool any faster.Be careful not to cover the sensor located on the
top of the instrument panel near the windshield. This
sensor regulates air temperature based on sun
load, and also turns on your headlamps.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until warm air is
available. The length of delay depends on the
engine coolant temperature. Pressing the fan switch
will override this delay and change the fan to a
selected speed.
9(Off):Press this button to turn off the entire climate
control system. Outside air will still enter the vehicle, and
will be directed to the ¯oor. This direction can be changed
by pressing the mode button. The temperature can also
be adjusted using either temperature knob. Press the up
or down arrows on the fan switch, the defrost button, the
AUTO button, or the air conditioning button to turn the
system on when it is off.
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Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for several seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for several seconds,
then it will ¯ash for several
more.
If the driver's belt is already buckled, neither the chime
nor the light will come on.
Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel cluster, which shows the air bag symbol.
The system checks the air bag's electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the air bag
sensors, the air bag modules, the passenger sensing
system (if equipped), the wiring and the crash sensing
and diagnostic module. For more information on the
air bag system, see
Air Bag Systems on page 1-64.
This light will come on
when you start your
vehicle, and it will ¯ash for
a few seconds. Then
the light should go out.
This means the system is
ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.
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