2006 GMC SIERRA 1500 ECO mode

When the vehicle detects a loss of traction, the system
will automatically engage four-wheel drive. Driving in
this mode results in slightly lower fuel economy than
Two-Wheel High.
2
m(Two-Wheel High):This setting is used for driving
in most street and highway situations. Your front axle is
not engaged in two-wheel drive. This setting also
provides the best fuel economy.
{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 2-52.
N (NEUTRAL):Shift the vehicle’s transfer case to
N (NEUTRAL) only when towing your vehicle. See
Recreational Vehicle Towing on page 4-62orTowing
Your Vehicle on page 4-62for more information.4
m(Four-Wheel High):Use this setting when you
need extra traction, such a on snowy or icy roads or in
most off-road situations. This setting also engages your
front axle to help drive your vehicle. This is the best
setting to use when plowing snow.
4
n(Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. You may never
need Four-Wheel Low. It sends maximum power to all
four wheels. You might choose Four-Wheel Low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills. When
operating in Four-Wheel Low, the gear ratio provides
additional torque when compared to four-wheel high.
The transmission gear shift feel will be exaggerated.
Indicator lights in the switches show which setting your
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
the transfer case is being shifted. It will stay on 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.
If the SERVICE 4WD message stays on, you should take
your vehicle to your dealer for service. SeeDIC Warnings
and Messages on page 3-55for further information.
2-43

Shifting into Four-Wheel High or AUTO
4WD (Automatic Four-Wheel Drive)
Press and release the four-wheel high or AUTO 4WD
switch. This can be done at any speed, except when
shifting from Four-Wheel Low, and the indicator light
will ash while shifting. It will remain on when the shift is
completed.
Shifting into Two-Wheel High
Press and release the Two-Wheel High switch.
This can be done at any speed, except when shifting
from Four-Wheel Low.
Shifting into Four-Wheel Low
Notice:Shifting the transfer case into
Four-Wheel Low while moving at speeds faster
than 3 mph (5 km/h) may cause premature wear
to the transfer case, and may cause the gears to
grind. To avoid causing premature wear, and
grinding the gears, do not shift the transfer case
into Four-Wheel Low while the vehicle is moving
faster than 3 mph (5 km/h).To shift to Four-Wheel Low, the ignition must be in RUN
and the vehicle must be stopped or moving less than
3 mph (5 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into Four-Wheel Low is
to have your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
Press and release the Four-Wheel Low switch. You must
wait for the Four-Wheel Low indicator light to stop
ashing and remain on before shifting your transmission
in gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Low indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for the
Four-Wheel Low indicator light to stop ashing
before shifting the transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
Four-Wheel Low and Four-Wheel High ranges or from
NEUTRAL (N) with the engine running.
If the Four-Wheel Low switch is pressed when your
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light will ash for 30 seconds and not complete
the shift unless your vehicle is moving less than
3 mph (5 km/h) and the transmission is in NEUTRAL (N).
After 30 seconds the transfer case will shift to four-wheel
high mode.
2-44

7. If the engine is running, shift the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second, or
FIRST (1) for vehicles equipped with a manual
transmission.
8. Turn the engine off, by turning the key to
ACCESSORY.
9. Place the transmission shift lever in PARK (P).
10. Turn the ignition to LOCK.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Turn the ignition to RUN with the engine off.
3. Shift the transmission to NEUTRAL (N).
4. Press the button for the desired transfer case
shift position (Two-Wheel High, Four-Wheel
High, AUTO 4WD, or Four-Wheel Low).
5. After the transfer case has shifted out of NEUTRAL
the red light will go out.
6. Release the parking brake.
7. You may start the engine and shift the transmission
to the desired position.Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
Electronic Transfer Case
If your four-wheel-drive
vehicle has the electronic
transfer case, the transfer
case switches are located
to the left of the instrument
panel cluster.
2-46

4. Shift the transfer case to Two-Wheel High.
5. Simultaneously press and hold the Two-Wheel High
and Four-Wheel Low buttons for 10 seconds. The
red NEUTRAL light will come on when the transfer
case shift to NEUTRAL is complete.
6. Start the engine if it is not already running.
7. Press and hold the foot brake pedal and Shift the
transmission to REVERSE (R) for one second, then
shift the transmission for one second to DRIVE (D)
for an automatic transmission, or FIRST (1) for
vehicles equipped with a manual transmission and
then let out the clutch. This is to ensure the transfer
case is in NEUTRAL. If not, repeat this procedure
starting at Step 3.
8. Turn the engine off, by turning the key to
ACCESSORY.
9. Place the transmission shift lever in PARK (P)
for an automatic transmission, or FIRST (1) for
vehicles equipped with a manual transmission.
10. Turn the ignition to LOCK.Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and press and hold the
regular brake pedal.
2. Shift the transmission to NEUTRAL (N) for an
automatic transmission, or press the clutch pedal
for vehicles equipped with a manual transmission.
Then turn the ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (Two-Wheel High, Four-Wheel High, or
Four-Wheel Low).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. Release the parking brake.
6. You may start the engine and shift the transmission
to the desired position. Excessively shifting the
transfer case into or out of the different modes may
cause the transfer case to enter the shift protection
mode. This will protect the transfer case from
possible damage and will only allow the transfer
case to respond to one shift per 10 seconds.
The transfer case may stay in this mode for up
to three minutes.
7. After the transfer case has shifted out of NEUTRAL
the red light will go out.
2-51

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.
Compass Variance
Compass variance is the difference between earth’s
magnetic north and true geographic north. The mirror
is set to zone eight upon leaving the factory. It will be
necessary to adjust the compass to compensate for
compass variance if you live outside zone eight. Under
certain circumstances, such as during a long distance
cross-country trip, it will be necessary to adjust for
compass variance. If not adjusted to account for compass
variance, your compass could give false readings.To adjust for compass variance, do the following:
1. Find your current location and variance zone
number on the map.
2. Press and hold the on/off button for six seconds.
Release the button when ZONE is displayed.
The number shown is the current zone number.
3. Scroll through the zone numbers that appear in the
compass/temperature window on the mirror by
pressing the on/off button. Once you nd your zone
number, release the button. After about four
seconds, the mirror will return to the compass
display, and the new zone number will be set.
2-60

Automatic Dimming Mirror Operation
The automatic dimming mirror function is turned
on automatically each time the ignition is started. To
operate the automatic dimming mirror, do the following:
1. Make sure the green indicator light, located to the left
of the on/off button, is lit. If it’s not, press and hold the
on/off button for approximately six seconds until the
green light comes on, indicating that the mirror is in
automatic dimming mode.
2. Turn off the automatic dimming mirror function
by pressing and holding the on/off button for
approximately six seconds, until the green
indicator light turns off.
Compass Variance
The mirror is set in zone eight upon leaving the factory.
It will be necessary to adjust the compass to compensate
for compass variance if you live outside of zone eight.
Under certain circumstances, as during a long distance
cross-country trip, it will be necessary to adjust for
compass variance. Compass variance is the difference
between earth’s magnetic north and true geographic
north. If not adjusted to account for compass variance,
your compass could give false readings.To adjust for compass variance do the following:
1. Find your current location and variance zone
number on the following zone map.
2. Press and hold the on/off button until a Z and a
zone number appear in the display. The compass
is now in zone mode.
2-62

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 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.
Compass Variance
Compass variance is the difference between earth’s
magnetic north and true geographic north. The mirror
is set to zone eight upon leaving the factory. It will be
necessary to adjust the compass to compensate for
compass variance if you live outside zone eight. Under
certain circumstances, such as during a long distance
cross-country trip, it will be necessary to adjust for
compass variance. If not adjusted to account for compass
variance, your compass could give false readings.
2-64

Universal Home Remote
System Operation
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. 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 Universal Home Remote Transmitter.
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 steps.
Keep the original hand-held transmitter for use in other
vehicles as well as for future Universal Home Remote
programming. It is also recommended that upon the sale
of the vehicle, the programmed Universal Home Remote
buttons should be erased for security purposes. See
“Erasing Universal Home Remote Buttons” later in this
section or, for assistance, seeCustomer Assistance
Offices on page 7-4.
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 signal.
Programming Universal Home Remote
Follow these steps to program up to three channels:
1. Press and hold down the two outside Universal
Home Remote buttons, releasing only when the
Universal Home Remote 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 hand-held
transmitter to the remaining two Universal Home
Remote buttons.
2. Position the end of your hand-held transmitter
about 1 to 3 inches (3 to 8 cm) away from the
Universal Home Remote buttons while keeping
the indicator light in view.
3. Simultaneously press and hold both the desired
Universal Home Remote button 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 Universal Home Remote successfully
receives the frequency signal from the hand-held
transmitter. Release both buttons.
2-76