2003 GMC YUKON ECU

Mode 4:No automatic door unlock.
The following instructions tell you how to change the
automatic door unlock mode. Choose one of the
four programming options listed above before entering
the program mode. To enter the program mode, do
the following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.
2. Turn the key to RUN and LOCK twice. Then, with
the key in LOCK, release the turn
signal/multifunction lever. Once you do this, the
doors will lock and unlock, the horn will chirp twice,
and a 30-second timer will begin. You are now
ready to program the automatic door unlock feature.
3. Press the door unlock switch once. You will hear
one, two, three, or four chimes. The number of
chimes tells you which unlock mode is currently
selected. Continue to press the door unlock switch
until the number of chimes that you hear matches the
number of the mode that you want. If you take longer
than 30 seconds, the locks will automatically lock and
unlock and the horn will chirp twice to indicate that
you have left the program mode. If this occurs, you
can repeat the procedure beginning with Step 1 to
re-enter the programming mode.
You can exit the program mode any time by turning the
ignition to RUN (the doors will automatically lock and
unlock and the horn will chirp twice to indicate that youare leaving the program mode). If the lock/unlock
switches are not pressed while in the programming
mode, the current automatic settings will not be
modied.
See your dealer for more information.
Rear Door Security Locks
If your vehicle is equipped with this feature, you can
lock the rear side doors so they cannot be opened from
the inside by passengers.
This feature is located on
the inside edge of the rear
doors.
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To use one of the locks do the following:
1. Open one of the rear doors.
2. To engage the rear door security locks, move the
lever forward.
3. To disengage the lock, move the lever rearward.
4. Close the door.
5. Do the same thing to the other rear door.
The rear doors or your vehicle cannot be opened from
the inside when this feature is in use. If you want to
open the rear door while the security lock is engaged,
unlock the door and open the door from the outside.
Lockout Protection
This feature protects you from locking your key in the
vehicle when the key is in the ignition and a door
is open.
If the power lock switch is pressed when a door is open
and the key is in the ignition, all of the doors will lock
and then the driver’s door will unlock.
Liftgate
{CAUTION:
It Can be dangerous to drive with the liftgate
glass, liftgate or rear doors open because
carbon monoxide (CO) gas can come into your
vehicle. You can’t see or smell CO. It can
cause unconsciousness and even death.
If you must drive with the liftgate glass, liftgate
or rear doors open or if electrical wiring or
other cable connections must pass through
the seal between the body and the liftgate
glass, liftgate or rear doors:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed with the
setting on VENT or OUTSIDE AIR. That will
force outside air into your vehicle. See
“Comfort Controls”in the Index.
If you have air outlets on or under the
instrument panel, open them all the way.
See“Engine Exhaust”in the Index.
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Liftgate Glass and Liftgate
To open a mechanical lock system from the outside,
insert the key into the lock and turn it counterclockwise
to unlock the glass and liftgate.
The liftgate glass can be opened using the button on
the liftgate after the doors have been unlocked. This can
be done by using either the power door locks or the
remote keyless entry system.
To open the entire liftgate, lift the handle located in the
center of the door.
To lock a power lock system from the outside, insert the
key into the lock button and turn clockwise. All doors will
lock. You may also use the keyless entry system or the
power door locks to lock the liftgate and liftgate glass.
Panel Doors
To open the rear panel doors, you must open the
passenger’s side panel doorrst. If the door is locked,
insert your door key in the lock and turn it
counterclockwise to unlock it.To open the passenger’s side panel door, pull on the
handle and pull the door open.
To open the driver’s side panel door,rst open the
passenger’s side door. Then, pull the handle on the left
door edge out and pull the door open.
To close the doors, close the driver’s side doorrst.
After securely closing the door, close the passenger’s
side door. Make sure both doors are latched securely.
To lock the rear doors from outside the vehicle, put your
key in the lock and turn it clockwise. If you have
power door locks, you can lock the side doors as well
as the rear doors from inside the vehicle. For more
information, seePower Door Locks on page 2-8earlier
in this section.
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Lighted Visor Vanity Mirror
If equipped, pull the sun visor down and lift the mirror
cover to turn on the lamps. There is a slide switch
to adjust the brightness 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 may be equipped with a content
theft-deterrent alarm system.
With this system, the
security light 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 using the
remote keyless entry transmitter, the door does not
need to be open.
If the delayed locking feature is active, the alarm
will not be activated until all doors are closed
and the security light goes off.
3. Close all doors. The security light will stopashing
and stay solid. The light should go off after
approximately 30 seconds. The alarm is not armed
until the security light goes off.
If a door is opened without the key or the remote
keyless entry transmitter, the alarm will go off. Your
vehicle’s headlamps willash and the horn will sound for
about two minutes, then will turn off to save the
battery power.
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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
keyafterthe 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 light 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 when it should but the
vehicle’s headlampsash, check to see if the horn
works. The horn fuse may be blown. To replace
the fuse, seeFuses and Circuit Breakers on page 5-98.
If the alarm does not sound or the vehicle’s headlamps
do notash, the vehicle should be serviced by an
authorized service center.
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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 5-98.) 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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To change the preselected tilt position, adjust the
mirrors to the desired position while the vehicle is in
REVERSE (R). When the vehicle is shifted out of
REVERSE (R), this new position is saved in memory as
the tilt position.
You may be able to enabled/disable this feature through
the Driver Information Center. SeeDriver Information
Center (DIC) on page 3-53.
Outside Convex Mirror
Your passenger’s side mirror is convex. A convex
mirror’s surface is curved so you can see more from the
driver’s seat.
{CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
Outside Heated Mirrors
The outside rearview mirrors with this option have a
defrost mode.
To turn on the defrost feature, press the rear window
defogger button. See“Rear Window Defogger”
underDual Automatic Climate Control System on
page 3-26for further information.
OnStar®System
OnStar®uses global positioning system (GPS) satellite
technology, wireless communications, and state of
the art call centers to provide you with a wide range of
safety, security, information and convenience services.
An OnStar
®subscription plan is included in the price
of your vehicle. You can easily upgrade or extend your
OnStar
®services to meet your personal needs.
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OnStar®Steering Wheel Controls
g
: If your vehicle is
equipped with the steering
wheel control buttons
you can use them
to interact with the OnStar
®
system.
See the OnStar
®manual provided with your vehicle for
more information.
HomeLink®Transmitter
HomeLink®a combined universal transmitter and
receiver, provides a way to replace up to three
hand-held transmitters used to activate devices such as
gate operators, garage door openers, entry door
locks, security systems and home lighting. Additional
HomeLink
®information can be found on the internet at
www.homelink.com or by calling 1-800-355-3515.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions: (1)
this device may not cause harmful interference, and
(2) this device must accept any interference received,
including interference that may cause undesired
operation.
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