sensor CHEVROLET TAHOE 2003 2.G Owners Manual

When Should an Air Bag In¯ate?
Frontal Air Bags
The driver's and right front passenger's frontal air bags
are designed to in¯ate in moderate to severe frontal
or near-frontal crashes. But they are designed to in¯ate
only if the impact speed is above the system's
designed ªthreshold level.º
In addition, your vehicle has ªdual stageº frontal air
bags, which adjust the amount of restraint according to
crash severity. For moderate frontal impacts, these
air bags in¯ate 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 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 driver's and right front passenger's frontal
air bags are not designed to in¯ate in rollovers, rear
impacts, or in many side impacts because in¯ation
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 1-73. Side impact air
bags are designed to in¯ate in moderate to severe
side crashes. A side impact air bag will in¯ate if
the crash severity is above the system's designed
ªthreshold level.º The threshold level can vary with
speci®c vehicle design. Side impact air bags are
not designed to in¯ate in frontal or near-frontal impacts,
rollovers or rear impacts, because in¯ation would not
help the occupant. A side impact air bag will only deploy
on the side of the vehicle that is struck.
1-79

In many crashes severe enough to in¯ate 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 in¯ate only once. After an
air bag in¯ates, 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 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 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.
1-82

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 START or RUN. 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 3-39. If your rearview mirror doesn't have either of
the indicators pictured, then your vehicle doesn't 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.
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
1-83

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. See
Customer
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.)
1-88

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 asbright as usual. Make sure your instrument panel
brightness control is in the full bright position. See
ªInstrument Panel Brightness Controlº underInterior
Lamps on page 3-17.
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. See²Daytime Running Lamps (DRL)²later
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. See
Driver 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
3-15

periods after dawn and before sunset. Fully functional
daytime running lamps are required on all vehicles
®rst 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'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.
Shifting the transmission into PARK (P) will allow you to
idle the vehicle with the DRL off. The DRL will stay
off until you shift the transmission out of PARK (P).
This procedure applies only to vehicles ®rst sold in the
United States.
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
the 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 your fog lamps
in the dark without turning on your headlamps.
The fog lamps will go off whenever your high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
3-16

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
within ®ve 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 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.
3-26

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 1-73.
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.
Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
Passenger Air Bag Status Indicator ± United States
3-39

FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Press the select button will acknowledge this
message and clear it from the DIC display.
LEFT REAR DOOR AJAR
If the driver's side rear door is not fully closed, this
message will appear on the display and you will hear a
chime. Stop and turn off the vehicle, check the door
for obstacles, and close the door again. Check to see if
the message still appears on the DIC. Press the
select button to acknowledge the message and clear it
from the DIC display.
LOW COOLANT LEVEL
If your vehicle is equipped with a low coolant level
sensor, this message will appear on the DIC if
the engine coolant level is low. Adding coolant will clear
the message.
OIL LIFE RESET
This message will appear on the DIC display for about 10
seconds after the change engine oil message is reset.
OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced.
PASSENGER DOOR AJAR
If the passenger's door is not fully closed, this message
will appear on the display and you will hear a chime.
Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if the
message still appears on the DIC. Press the select
button to acknowledge the message and clear it from
the DIC display.
REAR ACCESS OPEN
If the liftgate is open while the ignition is in RUN, this
message will appear on the DIC display and you will hear
a chime. Turn the vehicle off and check the liftgate.
Restart the vehicle and check for the message on the DIC
display. Press the select button to acknowledge the
message and clear it from the DIC display.
3-67

SERVICE 4WD
If a problem occurs with the four wheel drive system
this message will appear on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the four wheel
drive system needs service. Press the select button to
acknowledge the message.
SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. If the message
appears turn off the vehicle. Restart the vehicle and
check for the message on the DIC display. If the
message is still displayed, or appears again when you
begin driving, the ride control needs service. Press
the select button to acknowledge the message.
RIGHT REAR DOOR AJAR
If the passenger's side rear door is not fully closed, this
message will appear on the display and you will hear
a chime. Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if
the message still appears on the DIC. Press the select
button to acknowledge the message and clear it
from the DIC display.
SERVICE STABILITY
If you ever see the SERVICE STABILITY message, it
means there may be a problem with your
Stabilitrak
žsystem. If you see this message try to reset
the system (stop; turn off the engine; then start the
engine again). If the SERVICE STABILITY message still
comes on, it means there is a problem. You should
see your dealer for service. The vehicle is safe to drive,
however, you do not have the bene®t of Stabilitrak
ž,
so reduce your speed and drive accordingly. Press the
select button to acknowledge the message and clear
it from the DIC display.
SERVICE TIRE MONITOR
This message will be displayed if one or more of the tire
monitor sensors have malfunctioned, or if all of the
tire monitor sensors have not been programmed
successfully. Press the select button or reset stem, to
clear it from the display. The message will reappear
at each ignition cycle until the system has been
serviced.
3-69