sensor CHEVROLET TAHOE 2004 2.G Owners Manual

When Should an Air Bag Inate?
Frontal Air Bags
The driver’s and right front passenger’s frontal air bags
are designed to inate in moderate to severe frontal
or near-frontal crashes. But they are designed to inate
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
inate 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 specic 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 inate in rollovers, rear
impacts, or in many side impacts because ination
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 deployment.
Side Impact Air Bags
Your vehicle may or may not have a side impact air
bag. SeeAir Bag Systems on page 1-74. Side impact air
bags are designed to inate in moderate to severe
side crashes. A side impact air bag will inate if
the crash severity is above the system’s designed
“threshold level.” The threshold level can vary with
specic vehicle design. Side impact air bags are
not designed to inate in frontal or near-frontal impacts,
rollovers or rear impacts, because ination would not
help the occupant. A side impact air bag will only deploy
on the side of the vehicle that is struck.
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{CAUTION:
When an air bag inates, 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 not get out of the vehicle after an air bag
inates, 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 inate 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 inate only once. After an
air bag inates, 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
ination. 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 qualied 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 air 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 inate) or not.
Accident statistics show that children are safer if they are
restrained in the rear rather than the front seat. General
Motors 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.
Your vehicle has a rear seat that will accommodate a
rear-facing child restraint. A label on your sun visor says,
“Never put a rear-facing child seat in the front.” This is
because the risk to the rear-facing child is so great, if the
air bag deploys.
{CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger’s air bag inates. This is because
CAUTION: (Continued)
CAUTION: (Continued)
the back of the rear-facing child restraint
would be very close to the inating air bag.
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 recommends that
rear-facing child restraints be secured in the
rear seat, even if the air bag is off.
The passenger sensing system is designed to turn off
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
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
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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.
Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether
this will affect my advanced air bag system?
A:Changing or moving any parts of the front seats,
safety belts, the air bag sensing and diagnostic
module (located under the driver’s seat), or
the inside rearview mirror can affect the operation
of the advanced air bag system. If you have
questions, call Customer Assistance. 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.)
1-89

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 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 3-56.
As with any vehicle, you should turn on the regular
headlamp system when you need them.
3-15

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.
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 daytimeWhen 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.
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
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.
To nd 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.
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.
3-28

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 1-74.
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.
When the ignition key is turned to RUN or START, the
passenger air bag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check. Then, after several more seconds,
the status indicator will light either ON or OFF, or either
the on or off symbol to let you know the status of the
right front passenger’s frontal air bag.
Passenger Air Bag Status Indicator – United States
Passenger
Air Bag Status
Indicator – Canada
3-42

CHECK OIL LEVEL
If your vehicle is equipped with an oil level sensor, and
the oil level in the vehicle is low, this message will
appear on the DIC. Check the oil level and correct it as
necessary. You may need to let the vehicle cool or
warm up and cycle the ignition to be sure this message
will clear. The message will clear itself after 10 seconds,
until the next ignition cycle. Once the problem is
corrected, press the select button to clear the message
from the DIC display.
CHECK TIRE PRESSURE
If your vehicle is equipped with the Tire Pressure
Monitor System, and a low tire pressure is detected in
any of the vehicle’s tires, this message will appear on the
DIC, along with a chime. Press the select button, or reset
stem, to acknowledge the message and clear it from the
DIC display. It will appear at each ignition cycle until the
tires are inated to the correct ination pressure.
CHECK WASHER FLUID
If the washer uid level is low, this message will appear
on the DIC. Press the select button to acknowledge
the message and clear it from the DIC display.
The message will clear itself after 10 seconds, or until
the next ignition cycle. Adding washer uid will clear the
message.
DRIVER DOOR AJAR
If the driver’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.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Stop the vehicle and let the
engine idle in PARK (P) to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to safe operating
temperature. To acknowledge this message press the
select button
ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. The message will clear when the engine has
cooled to a safe operating temperature.
3-70

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 to acknowledge this
message and clear it from the DIC display.
KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. Press the select button
to acknowledge the 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.
3-71