2003 GMC SIERRA DENALI sensor

When Should an Air Bag Inflate?
An air bag is designed to inflate in a moderate to severe
frontal, or near-frontal crash. The air bag will inflate
only
if the impact speed is above the system’s designed
“threshold level.”
In addition, your vehicle has “dual stage” frontal air
bags, which adjust the amount of restraint according to
crash severity. For moderate frontal impacts, these
air bags inflate at a level less than full deployment. For
more severe frontal impacts, full deployment occurs.
If the front of your vehicle goes straight into a wall that
doesn’t move or deform, the threshold level for the
reduced deployment is about
10 to 16 mph
(16 to 25 km/h), and the threshold level for a full
deployment is about
20 to 25 mph (32 to 40 km/h). The
threshold level can vary, however, with specific
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 inflate in
rollovers, rear impacts, or in many side impacts because
inflation would not help the occupant.
In any particular crash, no one can say whether an air
bag should have inflated simply because of the damage
to a vehicle or because of what the repair costs were. Inflation
is determined by the angle of the impact and
how quickly the vehicle slows down in frontal or
near-frontal impacts.
The air bag system
is designed to work properly under
a wide range
of conditions, including off-road usage.
Observe safe driving speeds, especially on rough
terrain.
As always, wear your safety belt. See “Off-Road
Driving” in the Index for more tips on off-road driving.
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 depoyment.
What Makes an Air Bag Inflate?
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
inflator, which inflates the air bag. The inflator, 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.
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When an air bag inflates, there is dust in the
air. This dust could cause breathing problems
for people with
a history of asthma or other
breathing trouble.
To avoid this, everyone in
the vehicle should get out as soon as it is safe
to do
so. If you have breathing problems but
can’t get out of the vehicle after an air bag
inflates, then get fresh air by opening a
window or
a door. If you experience breathing
problems following an air bag deployment, you
should seek medical attention.
In many crashes severe enough to inflate the air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from the
right front passenger air bag.
Air bags are designed to inflate only once. After
they inflate, you’ll need some new parts for your
air bag system.
If you don’t get them, the air
bag system won’t be there to help protect you in
another crash.
A new system will include air
bag modules and possibly other parts. The service
manual for your vehicle covers the need to
replace other parts.
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
are bag inflation. 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 qualified technicians work on your air bag
systems. Improper service can mean that an air
bag system won’t 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.
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Passenger Air Bag
Status
Indicator
- Canada
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
inflate) or not. The passenger
sensing system is designed to turn
oft
the right front passenger’s frontal air bag if:
the right front passenger seat is unoccupied
the system determines that an infant is present in a
rear-facing infant seat
J the system determines that a small child is present
in a forward-facing child restraint
the system determines that a small child is present
in a booster seat,
0 a right front passenger takes hidher weight off of
the seat for a period of time
the right front passenger seat is occupied by a
smaller person, such as a child who has outgrown
child restraints or a very small person
the air bag off switch is in the off position
or if there is a critical problem with the air bag
system or the passenger sensing system
When the passenger’s frontal air bag has been turned
off either by the passenger sensing system or by the air
bag
off switch, the off indicator will light and stay lit to
remind you that the air bag is
off.
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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
inflate 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
Order’ Information
on page 7- 10.
E
For up to 1 minute after the il tiol :ey is
turned off and the battery is disconnected, an
air bag can
still inflate during improper
service. You can be injured if you are close to
an air bag when
it inflates. 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 qualified to do so.
Adding Equipment to Your Air
Bag-Equipped Vehicle
Q: Is there anything I might add to the front or
sides of the vehicle that could keep the air
bags from working properly?
frame, bumper system, front end or side 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. See
Customer Satisfaction
Procedure
on page 7-2.
A: Yes. If you add things that change your vehicle’s
The air bag system does not need regular maintenance.
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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 headlamp off delay,
which will keep the headlamps on for a short time after
the ignition is turned
off. For more information see
DIC Operation and Displays on page 3-43.
Your vehicle has 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. 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 sure your instrument panel
brightness control is in the full bright position. See
“Instrument Panel Brightness Control’’ under
Interior
Lamps on page
3-15.
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.
Your headlamps will also stay on after you exit the
vehicle. You can program this feature using the Driver
lnforrnation Center. See
Driver lnforrnation Center @IC)
on page
3-43
As with any vehicle, you should turn on the regular
headlamps
if 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.
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
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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
first sold in Canada.
The DRL system will come on when the following
conditions are met:
The ignition is on,
0 the exterior lamp control is in AUTO
0 the automatic transmission is not in PARK (P), and
0 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.
W-hen you turn the exterior iamp controi
to off, the
headlamps will go off, and your DRL lamps will
illuminate, provided it is not dark outside.
Shifting the transmission into PARK
(P) will 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).
Puddle Lamps
Your vehicle is equipped with puddle lamps to help you
see the area near the base
of the front doors when it
is dark out. The puddle lamps will illuminate when a door
is opened or when you press the UNLOCK button on
the keyless entry transmitter.
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2. Set the driver’s and passenger’s temperature.
To find your comfort setting, start with a
74°F
(23°C) 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
60°F
(15°C) the system will remain at the maximum
cooling setting. If you choose the temperature
setting of
90°F (32°C) 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.
Manual Operation
To change the current setting, select one of the
following:
A 8f? v (Fan): This button allows you to manually
adjust the fan speed. Press the up arrow
to increase fan
speed and the down arrow
to decrease fan speed.
4d (Mode): Press this button to manually change the
direction of the airflow in your vehicle; keep pressing the
button until the desired mode appears on the display.
If you press the mode button
to select an air delivery
mode, the display will change
to show you the selected
air mode delivery. The display will then show the
current status of the system. When the system is turned
off, the display will go blank after displaying the
current status
of the system.
f;’ (Vent): This mode directs air to the instrument
panel vents.
+2 (Bi-Level): This mode directs half of the air to the
instrument panel vents, then directs the remaining air
to
the floor vents. A little air is directed toward the
windshield and the side window vents. Cooler air is
directed
to the upper vents and warmer air to the floor
vents.
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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 1-57.
This light will come on
when you start your
vehicle, and it will flash 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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