sensor GMC YUKON 2003 Owner's Manual

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 driver’s and right front passenger’s frontal
air bags are not designed to inflate in rollovers, rear
impacts, or in many side impacts because inflation
would not help the occupant.
Seat Position Sensors
Vehicles 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.
Side Impact Air Bags
Your vehicle may or may not have a side impact air
bag. SeeAir Bag Systems on page 1-70. Side impact air
bags are designed to inflate in moderate to severe
side crashes. A side impact air bag will inflate if
the crash severity is above the system’s designed
“threshold level.”The threshold level can vary with
specific vehicle design. Side impact air bags are
not designed to inflate in frontal or near-frontal impacts,
rollovers or rear impacts, because inflation would not
help the occupant. A side impact air bag will only deploy
on the side of the vehicle that is struck.
Air Bag Systems
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.
For frontal air bags, inflation is determined by the angle
of the impact and how quickly the vehicle slows down
in frontal and near-frontal impacts. For side impact
air bags, inflation is determined by the location
and severity of the impact.
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 with Your Four-Wheel Drive Vehicle in the
Index for tips on off-road driving.
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In many crashes severe enough to inflate an 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 an
air bag inflates, 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, or the air bag
covering on the driver’s and right front passenger’s
seatback, the bag may not work properly. You may
have to replace the air bag module in the steering
wheel, both the air bag module and the instrument
panel for the right front passenger’s air bag, or both
the air bag module and seatback for the driver’s and
right front passenger’s side impact air bag. Do not
open or break the air bag coverings.
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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.
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
General Motors, therefore, recommends that child
restraints be secured in a rear seat, including an infant
riding in a rear-facing infant seat, a child riding in a
forward-facing child seat and an older child riding in a
booster seat. Never put a child in rear-facing child
restraint in the right front passenger seat unless your
vehicle has the passenger sensing system and the
passenger air bag status indicator shows off. Never put
a rear-facing child restraint in the right front passenger
seat unless the air bag is off.
{CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger’s air bag inflates. This is because
the back of the rear-facing child restraint
would be very close to the inflating air bag. Be
sure the air bag is off before using a
rear-facing child restraint in the right front seat
position.
Even though the passenger sensing system is
designed to turn off the passenger’s frontal air
bag if the system detects a rear-facing child
restraint, no system is fail-safe, and no one
can guarantee that an air bag will not deploy
under some unusual circumstance, even
though it is turned off. General Motors,
therefore, recommends that rear-facing child
restraints be secured in the rear seat whenever
possible, even if the air bag is off.
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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?
A:Yes. If you add things that change your vehicle’s
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. SeeCustomer
Satisfaction Procedure on page 7-2.
Restraint System Check
Checking Your Restraint Systems
Now and then, make sure the safety belt reminder light
and all your belts, buckles, latch plates, retractors
and anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from doing
its job, have it repaired.
Torn or frayed safety belts may not protect you in a
crash. They can rip apart under impact forces. If a belt
is torn or frayed, get a new one right away.
Also look for any opened or broken air bag covers, and
have them repaired or replaced. (The air bag system
does not need regular maintenance.)
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AUTO (Automatic):Turning the control to this position
puts the system into automatic headlamp mode. An
indicator light will illuminate when this position is
selected.
;(Parking Lamps):Turning the control to this
position turns on the parking lamps, together with the
following:
•Sidemarker Lamps
•Taillamps
•License Plate Lamps
•Instrument Panel Lights
•Roof Marker Lamps (If Equipped)
5(Headlamps):Turning the control to this position
turns on the headlamps, together with the previously
listed lamps and lights.
You can switch your headlamps from high to low-beam
by pushing the turn signal/high-beam lever towards
the instrument panel.
A circuit breaker protects your headlamps. If you have
an electrical overload, your headlamps willflicker on and
off. Have your headlamp wiring checked right away if
this happens.
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.
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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 sure your instrument panel
brightness control is in the full bright position. See
“Instrument Panel Brightness Control”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.
Your headlamps will also stay on after you exit the
vehicle. You can program this feature using the Driver
Information Center. SeeDriver Information Center (DIC)
on page 3-53.
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
first sold in Canada.
The DRL system will come on when the following
conditions are met:
•the ignition is on,
•the exterior lamps control is AUTO,
•the automatic transmission is not in PARK (P),
•the light sensor determines it is daytime and
When the DRL are on, only your DRL lamps will be on.
The taillamps, sidemarker and other lamps won’tbe
on. The instrument panel won’t be lit up either.
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Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature, the
air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will change to
show the current driver’s set temperature, delivery
mode and fan speed. Press the AUTO button again
withinfive seconds to display the passenger’s set
temperature.
If the driver and passenger’s temperature settings
are not the same, the opposite side temperature
setting will be displayed for an additionalfive
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 40°F(4°C). 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.
Tofind 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’sor
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.
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The safety belt light will
also come on and stay on
for several seconds, then it
willflash 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, seeAir Bag Systems on page 1-70.This light will come on
when you start your
vehicle, and it willflash 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.Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
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*1—Gasoline Engine and Fuel Injection Rail #2.
*2—Gasoline Engine and Fuel Injection Rail #1.
*3—Gasoline Engine; Oxygen Sensors.
*4—Gasoline Engine; Oxygen Sensors.
*5—PCM Ignition
Fuses Usage
GLOW PLUG Not Used
CUST FEED Gasoline Accessory Power
STUD #1Auxiliary Power (Single
Battery and Diesels
Only)/Dual Battery (TP2) Do
not install fuse.
MBECMid Bussed Electrical Center
Power Feed, Front Seats,
Right Doors
BLOWER Front Climate Control Fan
LBECLeft Bussed Electrical Center,
Door Modules, Door Locks,
Auxiliary Power Outlet—Rear
Cargo Area and Instrument
Panel
STUD 2Accessory Power/Trailer
Wiring Brake Feed
ABS Anti-Lock Brakes
Fuses Usage
VSES/ECAS Vehicle Stability
IGN A Ignition Power
IGN B Ignition Power
LBEC 1Left Bussed Electrical Center,
Left Doors, Truck Body
Controller, Flasher Module
TRL PARK Parking Lamps Trailer Wiring
RR PARKRight Rear Parking and
Sidemarker Lamps
LR PARKLeft Rear Parking and
Sidemarker Lamps
PARK LP Parking Lamps Relay
STARTER Starter Relay
INTPARK Interior Lamps
STOP LP Stoplamps
TBC BATTTruck Body Controller Battery
Feed
SUNROOF Sunroof
SEO B2 Off-Road Lamps
4WSVent Solenoid
Canister/Quadrasteer Module
Power
RR HVAC Rear Climate Control
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