2005 GMC YUKON ECU

To replace the battery in the keyless entry transmitter,
do the following:
1. Insert a thin object, such as a coin, in the slot
between the covers of the transmitter housing
near the key ring hole. Remove the bottom
by twisting the coin.
2. Remove and replace the battery with a
three-volt CR2032 or equivalent battery,
positive (+) side up.
3. Align the covers and snap them together.
4. Resynchronize the transmitter. See
“Resynchronization” following this information.
5. Check the operation of the transmitter.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.
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3. You are now ready to program the automatic door
locks. Select one of the four programming options
listed previously, and press the unlock side of
the power door lock switch to cycle through the
unlocking options. You will have 30 seconds
to begin programming. If you exceed the 30-second
limit, 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,
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 locks will automatically lock and
unlock and the horn will chirp twice to indicate that you
are leaving the program mode. If the lock/unlock switches
are not pressed while in the programming mode, the
current auto lock/unlock setting 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.
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.
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The rear doors of 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 cannot 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
Climate Control System on page 3-21.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-39.
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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.
Content Theft-Deterrent
Your vehicle may be equipped with a content
theft-deterrent alarm system.
The security light, located
on the instrument panel
cluster, will ash as
you open the door, while
the ignition is off, to
indicate the system is
being activated.This message reminds you to activate the theft-deterrent
system. Here is 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 and ash. 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 stop ashing
and go off after approximately 30 seconds. The
content theft deterrent alarm is not armed until the
security light goes off.
If a door is opened without using the key or the remote
keyless entry transmitter, the alarm will go off. Your
vehicle’s headlamps will ash and the horn will sound for
about two minutes, then will turn off to save the
battery power.
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The theft-deterrent system will not 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 is how to avoid setting off the alarm by accident:
If you do not 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 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 headlamps ash, check to see if the horn
works. The horn fuse may be blown. To replace the
fuse, seeFuses and Circuit Breakers on page 5-105.
If the alarm does not sound or the vehicle’s headlamps
do not ash, see your dealer for service.
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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 light ashes,
wait until the light stops ashing 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 5-105. See your
dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-5.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not 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 rst 500 miles (805 km).
Do not drive at any one speed, fast or slow, for
the rst 500 miles (805 km). Do not make
full-throttle starts.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time your new
brake linings are not 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.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-67for more information.
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OnStar®System
OnStar®uses global positioning system (GPS) satellite
technology, wireless communications, and call centers
to provide you with a wide range of safety, security,
information, and convenience services.
A complete OnStar
®user’s guide and the terms and
conditions of the OnStar®Subscription Service
Agreement are included in the vehicle’s glove box
literature. For more information, visit www.onstar.com or
www.onstarcanada.com. Contact OnStar
®at
1-888-4-ONSTAR (1-888-466-7827), or press the
OnStar
®button to speak to an OnStar®advisor 24 hours
a day, 7 days a week.
Terms and conditions of the Subscription Service
Agreement can be found at www.onstar.com or
www.onstarcanada.com.
OnStar®Services
For new vehicles equipped with OnStar®, the Safe and
Sound Plan is included for the rst year. You can
extend this plan beyond the rst year, or upgrade to the
Directions and Connections Plan to meet your needs.
For more information, press the OnStar
®button to speak
with an advisor.
Safe and Sound Plan

Automatic Notication of Airbag Deployment
Emergency Services
Roadside Assistance
Stolen Vehicle Tracking
AccidentAssist
Remote Door Unlock/Vehicle Alert
Remote Diagnostics
Online Concierge
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HomeLink®Wireless Control
System
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.This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
(1) this device may not cause interference, and (2) this
device must accept any interference, including
interference that may cause undesired operation of the
device.
Changes and modications to this system by other than
an authorized service facility could void authorization
to use this equipment.
HomeLink®Wireless Control
System Operation
Do not use the HomeLink®Transmitter with any garage
door opener that does not have the “stop and reverse”
feature. This includes any garage door opener model
manufactured before April 1, 1982. If you have a newer
garage door opener with rolling codes, please be
sure to follow Steps 6 through 8 to complete the
programming of your HomeLink
®Transmitter.
Read the instructions completely before attempting to
program the HomeLink
®Transmitter. Because of
the steps involved, it may be helpful to have another
person available to assist you in programming the
transmitter.
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