2004 GMC ENVOY XL ECO mode

In many crashes severe enough to inate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from
the right front passenger air bag.
Air bags are designed to inate only once. After
an air bag inates, you’ll need some new parts
for your air bag system. If you don’t get them,
the air bag system won’t be there to help protect
you in another crash. A new system will include
air bag modules and possibly other parts. The
service manual for your vehicle covers the need
to replace other parts.
Your vehicle is equipped with electronic frontal
sensors, which help the sensing system distinguish
between a moderate frontal impact and a more
severe frontal impact. Your vehicle is also equipped
with a crash sensing and diagnostic module,
which records information about the frontal air bag
system. The module records information about
the readiness of the system, when the system
commands air bag ination and driver’s safety belt
usage at deployment. The module also records
speed, engine rpm, brake and throttle data.
Let only qualied technicians work on your air bag
systems. Improper service can mean that an air
bag system won’t work properly. See your dealer
for service.
Notice:If you damage the covering for the driver’s
or the right front passenger’s air bag, or the air bag
covering on the driver’s and right front passenger’s
seatback, the air bag may not work properly.
You may have to replace the air bag module in the
steering wheel, both the air bag module and the
instrument panel for the right front passenger’s air
bag, or both the air bag module and seatback for the
driver’s and right front passenger’s side impact air
bag. Do not open or break the air bag coverings.
1-58

Programmable Locking Feature
The following is the list of available programming options:
Mode 1:All doors lock when the transmission is
shifted into gear.
Mode 2:All doors lock when the vehicle speed is
greater than 8 mph (13 km/h).
Mode 3:No automatic door locking.
The automatic door locks were pre-programmed at the
factory to lock all the doors when the transmission
is shifted into gear. The following instructions detail how
to program your door locks differently than the factory
setting. Choose one of the three 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, you will hear the lock switch
lock and unlock, the horn will chirp twice, and a
30 second program timer will begin.3. You are now ready to program the automatic door
locks. Select one of the three programming options
listed above, and press the lock side of the power
door lock switch to cycle through the lock 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.
2-11

Programmable Unlocking Feature
The following is the list of available programming
options:
Mode 1:Driver’s door unlocks when the transmission
is shifted into PARK (P).
Mode 2:All doors unlock when the transmission is
shifted into PARK (P).
Mode 3:All doors unlock when the key is removed
from the ignition.
Mode 4:No automatic door unlock.
The automatic door locks were pre-programmed at the
factory to unlock the driver’s door once the transmission
is shifted to PARK (P). The following instructions detail
how to program your door locks differently than the
factory setting. Choose one of the four programming
options listed above before entering the program mode.
To enter the program mode you need to 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, you will hear the lock switch
lock and unlock, the horn will chirp twice, and a
30 second program timer will begin.
3. You are now ready to program the automatic door
locks. Select one of the four programming options
listed above, 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.
2-12

2HI (Two-Wheel High):This setting is for driving in
most street and highway situations. Your front axle is
not engaged in two-wheel drive. It also provides the best
fuel economy.
A4WD (Automatic Four-Wheel Drive):This setting is
ideal for use when road conditions are variable. When
driving your vehicle in A4WD, the front axle is engaged,
but the vehicle’s power is sent to the rear wheels. When
the vehicle senses a loss of traction, the system will
automatically engage four-wheel drive. Driving in this
mode results in slightly lower fuel economy than 2HI.
4HI (Four-Wheel High):Use 4HI when you need
extra traction, such as on snowy or icy roads or in
most off-road situations. This setting also engages
your front axle to help drive your vehicle.
4LO (Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off-road in deep sand, deep mud,
and climbing or descending steep hills.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-29.
NEUTRAL:Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-45for more
information.
An indicator light in the knob will show you which position
the transfer case is in. The indicator lights will come on
briey when you turn on the ignition and one will stay on.
If the lights do not come on, you should take your vehicle
to your dealer for service. An indicator light will ash while
shifting the transfer case. It will remain illuminated when
the shift is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the last
chosen setting.
2-27

Mirrors
Automatic Dimming Rearview Mirror
with OnStar
®and Compass
Your vehicle may have an automatic-dimming rearview
mirror with a compass and the OnStar®system.
There are three additional buttons for the OnStar
®
system. See your dealer for more information on the
system and how to subscribe to OnStar®. SeeOnStar®
System on page 2-40for more information about the
services OnStar®provides.
Mirror Operation
When turned on, this mirror automatically dims to the
proper level to minimize glare from any headlamps
behind you after dark.
O(On/Off): This is the on/off button for the automatic
dimming feature and compass. Press the far left
button, located below the the mirror face, for up to
three seconds to turn the feature on and off. A light on
the mirror will be lit while the feature is turned on.
Compass Operation
Press the on/off button once to turn the compass on
or off.
There is a compass display in the window in the upper
right corner of the mirror face. The compass displays
a maximum of two characters. For example, “NE”
is displayed for north-east.
Compass Calibration
Press and hold the on/off button down for nine seconds
to activate the compass calibration mode. CAL will
be displayed in the compass window on the mirror.
The compass can be calibrated by driving the vehicle
in circles at 5 mph (8 km/h) or less until the display
reads a direction.
2-36

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.
2-43

Gate Operator and Canadian
Programming
Canadian radio-frequency laws require transmitter
signals to “time out” or quit after several seconds of
transmission. This may not be long enough for
HomeLink
®to pick up the signal during programming.
Similarly, some U.S. gate operators are manufactured to
“time out” in the same manner.
If you live in Canada, or you are having difficulty
programming a gate operator by using the
“Programming HomeLink
®” procedures (regardless of
where you live), replace Step 3 under “Programming
HomeLink
®” with the following:
Continue to press and hold the HomeLink
®button while
you press and release every two seconds (cycle)
your hand-held transmitter until the frequency signal has
been successfully accepted by HomeLink
®. The
indicator light will ash slowly at rst and then rapidly.
Proceed with Step 4 under “Programming HomeLink
®”
to complete.
Using HomeLink®
Press and hold the appropriate HomeLink®button for
at least half of a second. The indicator light will come
on while the signal is being transmitted.
Erasing HomeLink®Buttons
To erase programming from the three buttons do the
following:
1. Press and hold down the two outside buttons until
the indicator light begins to ash, after 20 seconds.
2. Release both buttons. Do not hold for longer than
30 seconds.
HomeLink
®is now in the train (learning) mode and
can be programmed at any time beginning with Step 2
under “Programming HomeLink
®.”
Individual buttons can not be erased, but they can
be reprogrammed. See “Reprogramming a Single
HomeLink
®Button” next.
2-45

Windshield Wipers
8
(Mist):For a single wiping cycle, turn the band to
mist. Hold it there until the wipers start. Then let go.
The wipers will stop after one wipe. If you want
more wipes, hold the band on mist longer.
9(Off):To stop the wipers, move the band to off.
N(Windshield Wipers):Turn the band to control the
windshield wipers.
You can set the wiper speed for a long or short delay
between wipes. This can be very useful in light rain
or snow. Turn the band to choose the delay time. The
closer to the top of the lever, the shorter the delay.
For steady wiping at low speed, turn the band away from
you to the rst solid band past the delay settings. For
high-speed wiping, turn the band further, to the second
solid band past the delay settings. To stop the wipers,
move the band to off.
Be sure to clear ice and snow from the wiper blades
before using them. If they’re frozen to the windshield,
carefully loosen or thaw them. If your blades do become
worn or damaged, get new blades or blade inserts.
Rainsense™ Wipers
Your vehicle may be equipped with Rainsense™
windshield wipers. When active, these wipers are able
to detect moisture on the windshield and automatically
turn on the wipers.
The moisture sensor is located next to the inside
rearview mirror and is mounted on the windshield.
To turn on the Rainsense™ feature, the wipers must be
set to one of the ve delay settings on the multifunction
lever. Each of the ve settings adjusts the sensitivity
of the rainsensor. For more wipes, select the higher
settings; for fewer wipes, select the lower settings
located closer to off on the multifunction lever.
The rainsensor will automatically control the frequency
of the wipes from off to high speed according to the
weather conditions. The wipers can be left in a
rainsense mode even when it is not raining.
Notice:If you do not turn off the windshield wipers
when driving through an automatic car wash,
you could damage the wipers. Always turn off the
windshield wipers before entering an automatic
car wash.
3-10