2003 GMC SIERRA ECU

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 inates. This is because
the back of the rear-facing child restraint
would be very close to the inating 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
CAUTION: (Continued)
CAUTION: (Continued)
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.
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
•a right front passenger takes his/her 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
•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
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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.
The passenger sensing system is designed to turn off
the passenger’s frontal air bag when a rear facing infant
seat, a forward-facing child restraint or a booster seat
is detected. If the child restraint has been installed
and the on indicator is lit, turn the vehicle off, remove
the child restraint from the vehicle and reinstall the
restraint following the child restraint manufacturer’s
directions and refer toSecuring a Child Restraint in the
Right Front Seat Position on page 1-49of this manual.
If after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, secure the child in
the child restraint in a rear seat position in the vehicle
and check with your dealer.
The passenger sensing system is designed to enable
(may inflate) the right front passenger’s frontal air
bag anytime the system senses that a person of adult
size is sitting properly in the right front passenger’s seat.
When the passenger sensing system has allowed the
air bag to be enabled, the on indicator will light and stay
lit to remind you that the air bag is active.For some children who have outgrown child restraints
and for very small adults, the passenger sensing system
may or may not turn off the right front passenger’s
frontal air bag, depending upon the person’s seating
posture and body build. Everyone in your vehicle
who has outgrown child restraints should wear a safety
belt properly—whether or not there is an air bag
for that person.
If a person of adult-size is sitting in the right front
passenger’s seat, but the off indicator is lit, it could be
because that person isn’t sitting properly in the seat
or the air bag off switch is in the off position. If this
happens and the switch is in the proper position, turn
the vehicle off and ask the person to place the seatback
in the full upright position, then sit upright in the seat,
centered on the seat cushion, with the person’s
legs comfortably extended. Restart the vehicle and have
the person remain in this position for about two
minutes. This will allow the system to detect that person
and then enable the passenger’s air bag.
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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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Resynchronization
Resynchronization may be necessary due to the security
method used by this system. The transmitter does not
send the same signal twice to the receiver. The receiver
will not respond to a signal that has been sent previously.
This prevents anyone from recording and playing back
the signal from the transmitter.
To resynchronize your transmitter, stand close to your
vehicle and press and hold the LOCK and UNLOCK
buttons on the transmitter at the same time for
15 seconds. The door locks should cycle to conrm
synchronization. If the locks do not cycle, see your dealer
for service.
Doors and Locks
Door Locks
{CAUTION:
Unlocked doors can be dangerous.
Passengers — especially children — can
easily open the doors and fall out of a
moving vehicle. When a door is locked, the
CAUTION: (Continued)
CAUTION: (Continued)
handle won’t open it. You increase the chance
of being thrown out of the vehicle in a crash if
the doors aren’t locked. So, wear safety belts
properly and lock the doors whenever you
drive.
Young children who get into unlocked
vehicles may be unable to get out. A child
can be overcome by extreme heat and can
suffer permanent injuries or even death
from heat stroke. Always lock your vehicle
whenever you leave it.
Outsiders can easily enter through an
unlocked door when you slow down or
stop your vehicle. Locking your doors can
help prevent this from happening.
To lock and unlock your vehicle, do one of the following:
You can use the keyless entry system,
use your key, or
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Tailgate
You can open the tailgate by lifting up on its handle
while pulling the tailgate toward you.
To shut the tailgate,rmly push it upward until it
latches.
After you put the tailgate back up, pull it back towards
you to be sure it latches securely.
Tailgate Removal
The tailgate on your vehicle can be removed to allow for
different loading situations. Although the tailgate can
be removed without assistance, you may want someone
to assist you with the removal to avoid possible
damage to the vehicle.
To remove the tailgate, do the following:1. Raise the tailgate
slightly and release
both retaining cable
clips. To release the
retaining cable clips, lift
the cable so it points
straight out and push
the cable clip forward.
2. With the tailgate at a
slight upward angle,
pull back on the tailgate
at the right edge and
then move the
tailgate to the right to
release the left edge.
Reverse the above procedure to reinstall. Make sure the
tailgate is secure.
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Sun Visors
To block out glare, you can swing down the top and
bottom visors. You can also swing the bottom visor from
side-to-side. The visors may also have an extension
that can be pulled out for additional glare protection.
Illuminated Visor Vanity Mirrors
Your vehicle may have this feature. If it does, pull the
sun visor down and lift the mirror cover to turn on
the lamps. There is a slide switch to adjust the intensity
of the lamps.
Theft-Deterrent Systems
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft-deterrent
features, we know that nothing we put on it can make it
impossible to steal. However, there are ways you
can help.
Content Theft-Deterrent
Your vehicle is equipped with a content theft-deterrent
alarm system.
With this system, the
security light on the cluster
willash as you open
the door (if your ignition is
off), to let you know
that you are activating the
system.
This message reminds you to activate the theft-deterrent
system. Here’s how to do it:
1. Open the door.
2. Lock the door with the power door lock switch or
the remote keyless entry transmitter. The security
light should come on andash. If you are using the
remote keyless entry transmitter, the door does
not need to be open.
3. Close all of the doors. The light will stopashing and
stay solid.The security light should go off after
approximately 30 seconds. The alarm is not armed
until the security light goes off. If the delayed locking
feature is active, the alarm will not activate until all
doors are closed and the security light goes off.
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Once the system is armed, if a door is opened without
the key or the remote keyless entry transmitter, the
alarm will go off. Depending on how you have
programmed the alarm in the secondary information
center, the horn may sound, the headlamps mayash
or both the headlamps and the horn will activate.
Remember, the theft-deterrent system won’t activate if
you lock the doors with a key or use the manual
door lock. It activates only if you use a power door lock
switch with the door open, or with the remote keyless
entry transmitter. You should also remember that
you can start your vehicle with the correct ignition key if
the alarm has been set off.
Here’s how to avoid setting off the alarm by accident:
If you don’t want to activate the theft-deterrent
system, the vehicle should be locked with the door
key after the doors are closed.
Always unlock a door with a key, or use the remote
keyless entry transmitter. Unlocking a door any
other way will set off the alarm if the system
has been armed.
If you set off the alarm by accident, unlock any door
with the key. You can also turn off the alarm by pressing
UNLOCK on the remote keyless entry transmitter or
by placing the key in the ignition and turning it to
START.
Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
power door lock switch while the door is open, or
with the remote keyless entry transmitter.
3. Get out of the vehicle, close the door and wait for
the security message to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door. This
should set off the alarm.
If the alarm does not sound and the headlamps do not
ash, you may have the feature turned off. SeeDIC
Operation and Displays on page 3-42for more
information.
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Passlock®
Your vehicle is equipped with the
Passlock®theft-deterrent system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder is
turned with a valid key. If a correct key is not used or the
ignition lock cylinder is tampered with, fuel is disabled.
If the engine stalls and the security lightashes,
wait until the light stopsashing before trying to restart
the engine. Remember to release the key from
START as soon as the engine starts.
If the engine is running and the security light comes on,
you will be able to restart the engine if you turn the
engine off. However, your Passlock
®system is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
®at this
time. You may also want to check the fuse (see
Fuses and Circuit Breakers on page 5-91.) See your
dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-5
under Customer Assistance Information.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle doesn’t need an elaborate
“break-in.”But it will perform better in the long run
if you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the first 500 miles (805 km).
•Don’t drive at any one speed — fast or
slow — for the first 500 miles (805 km).
Don’t make full-throttle starts.
•Avoid making hard stops for the first 200 miles
(322 km) or so. During this time your new
brake linings aren’t yet broken in. Hard stops
with new linings can mean premature wear and
earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
•Don’t tow a trailer during break-in. See “Towing
a Trailer” in the Index for more information.
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