2004 GMC ENVOY XL ECU

Passlock®
Your vehicle is equipped with 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 is tampered with, the fuel system is
disabled and the vehicle will not start.
During normal operation, the security light will turn off
approximately ve seconds after the key is turned
to 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. Your
vehicle is not protected by Passlock
®at this time. You
may also want to check the fuse. SeeFuses and Circuit
Breakers on page 5-97. See your dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-7.
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 4-55for more information.
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OnStar®System
Your vehicle may have this feature. 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.
A complete OnStar
®user’s guide and the terms and
conditions of the OnStar®Subscription Service
Agreement are included in your OnStar®-equipped
vehicle’s glove box literature. For more information, visit
www.onstar.com, contact OnStar
®at 1-888-4-ONSTAR
(1-888-466-7827), or press the blue OnStar®button
to speak to an OnStar®advisor 24 hours a day,
7 days a week.A completed Subscription Service Agreement is required
prior to delivery of OnStar
®services and prepaid
calling minutes are also required for OnStar®Personal
Calling and OnStar®Virtual Advisor use. Terms and
conditions of the Subscription Service Agreement can be
found at www.onstar.com.
OnStar®Services
One of the following plans is normally included for a
specic duration with each vehicle equipped with
OnStar
®. You can upgrade or extend your OnStar®
service plan to meet your needs.
Safe and Sound Plan

Automatic Notication of Air Bag Deployment
Emergency Services
Roadside Assistance
Stolen Vehicle Assistance
AccidentAssist
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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.If your vehicle is equipped with the HomeLink
®
Transmitter, it 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 received,
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.
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Programming the HomeLink®
Transmitter
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.
Keep the original transmitter for use in other vehicles as
well as for future HomeLink
®programming. It is also
recommended that upon the sale of the vehicle, the
programmed HomeLink
®buttons should be erased for
security purposes. Refer to “Erasing HomeLink®Buttons”
or, for assistance, contact HomeLink®on the internet at:
www.homelink.com or by calling 1-800-355-3515.
Be sure that people and objects are clear of the garage
door or gate operator you are programming. When
programming a garage door, it is advised to park outside
of the garage.It is recommended that a new battery be installed in
your hand-held transmitter for quicker and more
accurate transmission of the radio frequency.
Your vehicle’s engine should be turned off while
programming the transmitter. Follow these steps to
program up to three channels:
1. Press and hold down the two outside buttons,
releasing only when the indicator light begins to
ash, after 20 seconds. Do not hold down the
buttons for longer than 30 seconds and do not
repeat this step to program a second and/or third
transmitter to the remaining two HomeLink
®buttons.
2. Position the end of your hand-held transmitter about
1 to 3 inches (3 to 8 cm) away from the HomeLink
®
buttons while keeping the indicator light in view.
3. Simultaneously press and hold both the desired
button on HomeLink
®and the hand-held transmitter
button. Do not release the buttons until Step 4
has been completed.
Some entry gates and garage door openers may
require you to substitute Step 3 with the procedure
noted in “Gate Operator and Canadian
Programming” later in this section.
4. The indicator light will ash slowly at rst and then
rapidly after HomeLink
®successfully receives the
frequency signal from the hand-held transmitter.
Release both buttons.
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Luggage Carrier
{CAUTION:
If you try to carry something on top of your
vehicle that is longer or wider than the luggage
carrier — like paneling, plywood, a mattress and
so forth — the wind can catch it as you drive
along. This can cause you to lose control.
What you are carrying could be violently torn
off, and this could cause you or other drivers to
have a collision, and of course damage your
vehicle. You may be able to carry something like
this inside. But, never carry something longer
or wider than the luggage carrier on top of your
vehicle.
A luggage carrier allows you to load things on top of
your vehicle. The luggage carrier has side rails attached
to the roof, sliding crossrails (if equipped) and places
to use for tying things down. These let you load
some other things on top of your vehicle, as long as
they are not wider or longer than the luggage carrier.To slide the crossrails to where you want them, pull up
on the lever on each side of the crossrail. This will
release the crossrail and allow you to slide it. When the
crossrail is where you want it, press down on the
levers to lock it into place.
Notice:Loading cargo on the luggage carrier that
weighs more than 220 lbs (100 kg) or hangs over the
rear or sides of the vehicle may damage your vehicle.
Load cargo so that it rests on the slats as far forward
as possible and against the side rails, making sure to
fasten it securely.
Don’t exceed the maximum vehicle capacity when
loading your vehicle. For more information on vehicle
capacity and loading, seeLoading Your Vehicle on
page 4-49.
To prevent damage or loss of cargo as you’re driving,
check now and then to make sure the luggage carrier is
locked and cargo is still securely fastened.
When the luggage carrier is not in use, place the
crossrails at the following positions for wind noise
reduction. Place one crossrail at the rear most point of
the vehicle and the other crossrail above the opening
of the rear door.
2-48

Rear Storage Area
Rear Compartment Storage
Panel/Cover
Your vehicle may have this feature. This shelf position
is used as a cargo shade. Insert the front corners of the
panel into the top guides and slide the panel forward.
Press down on the back of the panel to lock it in place.
{CAUTION:
If you were to carry things on the adjustable
panel when it is in the upper (cargo cover)
position, then during a sudden vehicle
movement or a crash those things could be
thrown around in the vehicle. You or others
could be injured. When it is in the upper
position, always secure any cargo on the oor
beneath the panel/cover.
Upper Position
2-49

Rear Floor Storage Lid
{CAUTION:
If any removable convenience item is not
secured properly, it can move around in a
collision or sudden stop. People in the vehicle
could be injured. Be sure to secure any such
item properly.
Your vehicle has a rear cargo area with a removeable
storage lid.
To remove the rear oor storage lid, do the following:
1. Press the latch release and lift up the latch handle.
2. Raise the lid slightly to unhook it.
3. Pull the lid toward you to release it from the forward
mounting tabs.
To reinstall the rear oor storage lid, reverse the
previous steps. Make sure the lid is secure by applying
slight pressure to the latch until you hear it click.
Convenience Net
Your vehicle may have this feature. A convenience net
in the rear of your vehicle helps keep small items in
place during sharp turns or quick stops and starts.
The net is not designed to retain these items during
off-road use. The net is not for larger, heavier items.
To use the convenience net, do the following:
1. Attach the upper loops to the retainers on both
sides of the liftgate opening. The label should be
in the upper passenger’s side corner, visible
from the rear of the vehicle.
2. Attach the lower hooks to the rear cargo tie downs
on the oor.
2-51

Cargo Cover
If your vehicle has a cargo cover, you can use it to
cover items in the cargo area of your vehicle.
To install the cargo cover, do the following:
1. Align the endcap with the pocket in the trim panel
located behind the rear seat.
2. Compress the opposite endcap, align it with the
pocket located on the opposite side of the trim
panel and release.
3. Grasp the handle and unroll the cover. Latch the
posts into the sockets on the inside of the vehicle
to secure it.
To remove the cargo cover, do the following:
1. Release the cover from the latch posts and carefully
roll it back up.
2. Compress one endcap and remove it from the
pocket in the trim panel.
3. Remove the cargo cover from the other endcap so
that you can remove the shade from the vehicle.{CAUTION:
An improperly stored cargo cover could be
thrown about the vehicle during a collision or
sudden maneuver. You or others could be
injured. If you remove the cover, always store
it in the proper storage location. When you put
it back, always be sure that it is securely
reattached.
Cargo Tie Downs
There may be cargo tie
downs in the rear of your
vehicle that allow you
to strap cargo in and keep
it from moving.
2-52