2008 GMC ENVOY DENALI ECU

Rear Door Security Locks
Your vehicle may have this feature. You can lock the
rear doors so they cannot be opened from the inside by
passengers. To use one of these locks do the following:
1. Open one of the rear doors. You will nd a security
lock lever located on the inside edge of each
rear door.
2. Move the lever down
to engage the security
lock. Move the lever
up to disengage
the security lock.
3. Close the door.The rear doors of your vehicle cannot be opened from
the inside while this feature is in use. If you want to open
the rear door while the security lock is on, unlock the
door and open the door from the outside.
Lockout Protection
This feature stops the power door locks from locking
when the key is in the ignition and a door is open
to protect you from locking your key in the vehicle.
If the power lock switch is pressed when a door is open
and the key is in the ignition, all the doors will lock
and then the driver’s door will unlock.
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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 have a content theft-deterrent alarm
system.
The security light is
located on the instrument
panel cluster.To operate the system:
1. Open the door.
2. Lock the door with the power door lock switch
or the Remote Keyless Entry (RKE) transmitter.
The security light should ash.
The system will not activate if the doors are locked
with the key or manual door lock.
3. Close all doors. The security light should turn off
after about 30 seconds. The alarm is not armed
until the security light turns off.
If a locked door is opened without the key or the RKE
transmitter, the alarm will go off. The headlamps
and parking lamps will ash for two minutes, and the
horn will sound for 30 seconds, then will turn off to save
the battery power.
To avoid setting off the alarm by accident:
Always lock the vehicle using the door keyafterthe
doors are closed.
Always unlock a door with a key, or use the RKE
transmitter. Unlocking a door any other way will
set off the alarm.
To turn off the alarm, press unlock on the RKE
transmitter or unlock any door with the key.
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Testing the Alarm
To test the alarm:
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 RKE 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.
When the alarm is set the power door unlock switch will
not work.
If the alarm does not sound when it should but the
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 5-110.
If the alarm does not sound or the headlamps do
not ash, the vehicle should be serviced by your
dealer/retailer.
Passlock®(U. S. Only)
Your vehicle has the Passlock®theft-deterrent system.
Passlock®is a passive theft-deterrent system that
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 has been tampered with, the fuel system is
disabled and the vehicle will not start.
During normal operation, the security light will turn off
about ve seconds after the key is turned to ON/RUN.
If the engine stalls and the security light ashes,
wait about 10 minutes 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 does not start after three tries, the vehicle
needs service.
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/retailer.
Your vehicle is not protected by Passlock
®at this time.
You may also want to check the fuse. SeeFuses and
Circuit Breakers on page 5-110. See your dealer/retailer
for service.
In an emergency, call the Roadside Assistance Center.
SeeRoadside Assistance Program on page 7-8.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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PASS-Key®III+
The PASS-Key®III+ system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
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.
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.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
PASS-Key
®III+ uses a radio frequency transponder in
the key that matches a decoder in your vehicle.
PASS-Key®III+ Operation
(Canada Only)
Your vehicle has a passive theft-deterrent system.
The system is automatically armed when the key
is removed from the ignition.
The system is automatically disarmed when the key is
turned to ON/RUN.
You do not have to manually arm or disarm the system.
The security light will come on if there is a problem
with arming or disarming the theft-deterrent system.
The key uses a transponder that matches an immobilizer
control unit in your vehicle. Only the correct key will
start the vehicle. If the key is ever damaged, you may
not be able to start your vehicle.
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When trying to start the vehicle, if the engine does not
start and the security light comes on, there may be
a problem with your theft-deterrent system. Turn
the ignition off and try again.
If the engine still does not start, and the key appears to
be undamaged, try another ignition key. At this time,
you may also want to check the fuse. SeeFuses
and Circuit Breakers on page 5-110. If the engine still
does not start with the other key, your vehicle needs
service. If your vehicle does start, the rst key may be
faulty. See your dealer/retailer who can service the
theft-deterrent system and have a new key made.
It is possible for the theft-deterrent system decoder to
learn the transponder value of a new or replacement
key. Up to 10 keys may be programmed for the vehicle.
The following procedure is for programming additional
keys only.Canadian Owners:If you lose or damage your keys,
only a dealer/retailer can service the theft-deterrent
system to have new keys made. To program additional
keys you will require two current driver’s keys.
To program a new key do the following:
1. Verify that the new key has PK3+ stamped on it.
2. Insert the current driver’s key in the ignition
and start the engine. If the engine will not start
see your dealer/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the second current driver’s key in the ignition
and start the engine within ten seconds of removing
the previous key. If the engine will not start see
your dealer/retailer for service.
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5. After the engine has started, turn the key to
LOCK/OFF, and remove the key. Insert the key
to be programmed and turn it to ON within
ten seconds of removing the previous key.
The security light will turn off once the key has
been programmed.
6. Repeat the Steps 1 through 5 if additional keys are
to be programmed.
If the security light comes on and stays on while driving,
you will be able to restart the engine if you turn it off.
The theft-deterrent system, however, is not working
properly and must be serviced by your dealer/retailer.
Your vehicle is not protected by the theft-deterrent
system at this time.
In an emergency, contact Roadside Assistance.
SeeRoadside Assistance Program on page 7-8.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.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 constant speed, fast or
slow, for the rst 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting
to brake or slow the vehicle.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time the 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 4-45for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
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Outside Convex Mirror
{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.
The passenger side mirror is convex. A convex mirror’s
surface is curved so more can be seen from the
driver seat. It also makes things, like other vehicles,
look farther away than they really are.
Outside Heated Mirrors
Your vehicle may have this feature. When you operate
the rear window defogger, the defogger also warms the
heated driver’s and passenger’s outside rearview mirrors
to help clear them of ice, snow and condensation.
OnStar®System
OnStar uses several innovative technologies and live
advisors to provide you with a wide range of safety,
security, information, and convenience services. If your
airbags deploy, the system is designed to make an
automatic call to OnStar Emergency advisors who can
request emergency services be sent to your location.
If you lock your keys in the vehicle, call OnStar at
1-888-4-ONSTAR and they can send a signal to unlock
your doors. If you need roadside assistance, press
the OnStar button and they can contact Roadside
Service for you.
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Universal Home Remote
System
Universal Home Remote System
The Universal Home Remote System provides a way to
replace up to three hand-held Radio-Frequency (RF)
transmitters used to activate devices such as garage
door openers, security systems, and home lighting.
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.
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.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Universal Home Remote System
Operation (With One Triangular LED)
If there is one triangular Light Emitting Diode (LED)
indicator light above the Universal Home Remote
buttons, follow the instructions below.
This system provides a way to replace up to three
remote control transmitters used to activate devices
such as garage door openers, security systems,
and home automation devices.
Do not use the Universal Home Remote 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.
Read the instructions completely before attempting to
program the Universal Home Remote. Because of
the steps involved, it may be helpful to have another
person available to assist you in the programming
the Universal Home Remote.
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