CHEVROLET IMPALA 2004 8.G Repair Manual

If your vehicle has one, the driver’s side impact air bag is
in the side of the driver’s seatback closest to the door.
{CAUTION:
If something is between an occupant and an
air bag, the bag might not inate properly or it
might force the object into that person causing
severe injury or even death. The path of an
inating air bag must be kept clear. Do not put
anything between an occupant and an air bag,
and do not attach or put anything on the
steering wheel hub or on or near any other air
bag covering. Do not let seat covers block the
ination path of a side impact air bag.
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When Should an Air Bag Inate?
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 does not
move or deform, the threshold level for the reduced
deployment is about 12 to 18 mph (19 to 29 km/h), and
the threshold level for a full deployment is about 18 to
24 mph (29 to 38.5 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.Your vehicle may or may not have a driver’s side impact
air bag. SeeAir Bag Systems on page 1-51. A driver’s
side impact air bag is designed to inate in moderate to
severe side crashes involving the driver’s door. 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.
A driver’s side impact air bag is not designed to inate
in frontal or near-frontal impacts, rollovers or rear
impacts, because ination would not help the occupant.
In any particular crash, no one can say whether an
air bag should have inated simply because of
the damage to a vehicle or because of what the repair
costs were. For frontal air bags, ination 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, ination is determined by
the location and severity of the impact.
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What Makes an Air Bag Inate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. For
both the frontal and side impact air bags, the sensing
system triggers a release of gas from the inator, which
inates the air bag. The inator, air bag and related
hardware are all part of the air bag modules. Frontal air
bag modules are located inside the steering wheel
and instrument panel. For vehicles with a driver’s side
impact air bag, the air bag modules are located in
the seatback closest to the driver’s door.
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. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle.The air bag supplements 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 the frontal 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
the air bag. A side impact air bag would not help you in
many types of collisions, including frontal or near
frontal collisions, rollovers, and rear impacts, primarily
because an occupant’s motion is not toward that air bag.
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
for the driver’s and right front passenger’s frontal
air bags, and only in moderate to severe side collisions
for vehicles with a driver’s side impact air bag.
1-57

What Will You See After an Air Bag
Inates?
After the air bag inates, it quickly deates, so quickly that
some people may not even realize the air bag inated.
Some components of the air bag module will be hot for a
short time. These components include the steering wheel
hub for the driver’s frontal air bag and the instrument
panel for the right front passenger’s frontal air bag. For
vehicle’s with a driver’s side impact air bag, the side of
the seatback closest to the driver’s door will be hot. The
parts of the bag that come into contact with you may be
warm, but not too hot to touch. There will be some smoke
and dust coming from the vents in the deated air bags.
Air bag ination doesn’t prevent the driver from seeing or
being able to steer the vehicle, nor does it stop people
from leaving the vehicle.
{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.
Your vehicle has a feature that will automatically unlock
the doors and turn the interior lamps on when the air
bags inate (if battery power is available). You can lock
the doors again and turn the interior lamps off by
using the door lock and interior lamp controls.
1-58

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 an electronic frontal
sensor, which helps the sensing system distinguish
between a moderate frontal impact 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, when the system
commands air bag ination and driver’s safety belt
usage at deployment. 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 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 the air bag
module and seatback for the driver’s side impact air
bag. Do not open or break the air bag coverings.
1-59

Servicing Your Air Bag-Equipped
Vehicle
Air bags affect how your vehicle should be serviced.
There are parts of the air bag systems in several places
around your vehicle. Your dealer and the service manual
have information about servicing your vehicle and the air
bag systems. To purchase a service manual, seeService
Publications Ordering Information on page 7-12.
{CAUTION:
For up to 10 seconds after the ignition key is
turned off and the battery is disconnected, an
air bag can still inate during improper
service. You can be injured if you are close to
an air bag when it inates. 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 qualied to do so.
The air bag systems do not need regular maintenance.
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.)
1-60

Replacing Restraint System Parts
After a Crash
{CAUTION:
A crash can damage the restraint systems in
your vehicle. A damaged restraint system may
not properly protect the person using it,
resulting in serious injury or even death in a
crash. To help make sure your restraint
systems are working properly after a crash,
have them inspected and any necessary
replacements made as soon as possible.If you’ve had a crash, do you need new belts or LATCH
system parts?
After a very minor collision, nothing may be necessary.
But if the belts were stretched, as they would be if
worn during a more severe crash, then you need
new parts.
If the LATCH system was being used during a more
severe crash, you may need new LATCH system parts.
If belts are cut or damaged, replace them. Collision
damage also may mean you will need to have LATCH
system, safety belt or seat parts repaired or replaced.
New parts and repairs may be necessary even if the belt
or LATCH system wasn’t being used at the time of
the collision.
If an air bag inates, you’ll need to replace air bag
system parts. See the part on the air bag system earlier
in this section.
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✍NOTES
1-62

Keys...............................................................2-2
Remote Keyless Entry System.........................2-3
Remote Keyless Entry System Operation...........2-4
Doors and Locks.............................................2-8
Door Locks....................................................2-8
Power Door Locks..........................................2-9
Programmable Automatic Door Locks..............2-10
Lockout Protection........................................2-10
Leaving Your Vehicle....................................2-10
Trunk..........................................................2-11
Windows........................................................2-13
Power Windows............................................2-14
Sun Visors...................................................2-14
Theft-Deterrent Systems..................................2-15
Content Theft-Deterrent.................................2-15
Passlock
®....................................................2-16
Starting and Operating Your Vehicle................2-17
New Vehicle Break-In....................................2-17
Ignition Positions..........................................2-17
Starting Your Engine.....................................2-18
Engine Coolant Heater..................................2-20
Automatic Transaxle Operation.......................2-22
Parking Brake..............................................2-26
Shifting Into Park (P).....................................2-27Shifting Out of Park (P).................................2-30
Parking Over Things That Burn.......................2-30
Engine Exhaust............................................2-31
Running Your Engine While You Are Parked. . . .2-32
Mirrors...........................................................2-33
Manual Rearview Mirror.................................2-33
Manual Rearview Mirror with OnStar
®..............2-33
Automatic Dimming Rearview Mirror................2-34
Automatic Dimming Rearview Mirror
with OnStar
®............................................2-34
Outside Power Mirrors...................................2-35
Outside Convex Mirror...................................2-36
OnStar
®System.............................................2-36
HomeLink®Transmitter...................................2-38
Programming the HomeLink®Transmitter.........2-38
Storage Areas................................................2-42
Glove Box...................................................2-42
Front Storage Area.......................................2-42
Center Console Storage Area.........................2-42
Rear Storage Area........................................2-42
Convenience Net..........................................2-42
Sunroof.........................................................2-43
Vehicle Personalization...................................2-44
Section 2 Features and Controls
2-1

Keys
{CAUTION:
Leaving children in a vehicle with the ignition
key is dangerous for many reasons. They
could operate the power windows or other
controls or even make the vehicle move. The
children or others could be badly injured or
even killed. Do not leave the keys in a vehicle
with children.
2-2