2008 GMC YUKON XL ECO mode

Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel High or AUTO position.
This can be done at any speed, except when shifting
from Four-Wheel Drive Low. The indicator light will ash
while shifting. It will remain on when the shift is
completed.
Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel High position. This can
be done at any speed, except when shifting from
Four-Wheel Drive Low.
See shifting out of Four-Wheel Drive Low later in this
section for more information.
Shifting Into Four-Wheel Drive Low
When Four-Wheel Low is engaged, vehicle speed
should be kept below 45 mph. Extended high-speed
operation in 4L may damage or shorten the life of
the drivetrain.
To shift to the Four-Wheel Drive Low position, the
ignition must be in ON/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 Drive Low is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).Turn the knob to the Four-Wheel Drive Low position.
You must wait for the Four-Wheel Drive 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 Drive Low indicator light has
stopped ashing could damage the transfer case.
To help avoid damaging your vehicle, always
wait for the Four-Wheel Drive Low indicator light to
stop ashing before shifting the transmission
into gear.
The vehicle may have signicant engagement noise and
bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from NEUTRAL
while the engine is running.
If the knob is turned to the Four-Wheel Drive Low position
when your vehicle is in gear and/or moving, the
Four-Wheel Drive 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 Drive High mode.
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7. If the engine is running, verify that the transfer case
is in NEUTRAL (N) by shifting the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to moving
the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular
brake pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to ON/RUN with the engine off.
3. Turn the transfer case dial to the desired transfer
case shift position (Two-Wheel Drive High,
Four-Wheel Drive High, AUTO).
After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.4. Release the parking brake prior to moving the
vehicle.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped ashing could damage the transfer case.
To help avoid damaging your vehicle, always
wait for the Four-Wheel Drive Low indicator light to
stop ashing before shifting the transmission
into gear.
5. 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.
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Compass variance is the difference between earth’s
magnetic north and true geographic north. If not
adjusted to account for compass variance, the compass
could give false readings.
To adjust for compass variance:
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 appears in the display. The compass
is now in zone mode.3. Keep pressing the on/off button until the desired
zone number appears in the display. Release the
button. After approximately four seconds of
inactivity, the new zone number will be locked in
and the compass/temperature display will return.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
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2. Write down the eight to 12 switch settings from left
to right as follows:
When a switch is in the up position, write “Left.”
When a switch is in the down position, write
“Right.”
If a switch is set between the up and down
position, write “Middle.”
The switch settings that you wrote down in Step
2 will now become the button strokes you
enter into the Universal Home Remote in Step 4.
Be sure to enter the switch settings that you
wrote down in Step 2, in order from left to right,
into the Universal Home Remote, when
completing Step 4.
3. From inside your vehicle, rst rmly press all three
buttons at the same time for about three seconds.
Release the buttons to put the Universal Home
Remote into programming mode.4. The indicator lights will blink slowly. Enter each
switch setting from Step 2 into your vehicle’s
Universal Home Remote. You will have two and
one-half minutes to complete Step 4. Now
press one button on the Universal Home Remote
for each switch setting as follows:
If you wrote “Left,” press the left button in the
vehicle.
If you wrote “Right,” press the right button in the
vehicle.
If you wrote “Middle,” press the middle button in
the vehicle.
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L(Windshield Washer):SeeWindshield Washer on
page 3-11.
5(Rear Wiper Delay):SeeRear Window
Wiper/Washer on page 3-12.
Z(Rear Wiper):SeeRear Window Wiper/Washer on
page 3-12.
=(Rear Wiper Wash):SeeRear Window
Wiper/Washer on page 3-12.
Turn and Lane-Change Signals
The turn signal has two upward (for right) and two
downward (for left) positions. These positions allow you
to signal a turn or a lane change.
To signal a turn, move the lever all the way up or down.
When the turn is nished, the lever will return
automatically.
To signal a lane change, raise or lower the lever for less
than one second until the arrow starts to ash. This will
cause the turn signals to automatically ash three times.
It will ash six times if tow-haul mode is active. Holding
the turn signal lever for more than one second will cause
the turn signals to ash until you release the lever. The
lever will return by itself when it is released.An arrow on the instrument
panel cluster will ash in
the direction of the
turn or lane change.
As you signal a turn or a lane change, if the arrows
ash more quickly than normal, a signal bulb may
be burned out and other drivers will not see your turn
signal.
If a bulb is burned out, replace it to help avoid an
accident. If the arrows do not go on at all when you
signal a turn, check for burned-out bulbs and a blown
fuse. SeeFuses and Circuit Breakers on page 5-117.
Turn Signal On Chime
If your turn signal is left on for more than 3/4 of a mile
(1.2 km), a chime will sound at each ash of the
turn signal and the message TURN SIGNAL ON will
also appear in the Driver Information Control (DIC).
To turn the chime and message off, move the turn signal
lever to the off position.
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9(Off):To stop the wipers, move the band to off.
6(Delay):Turn the band to adjust the delay time. The
delay between wiping cycles becomes shorter as
the band is moved to the top of the lever. This can be
very useful in light rain or snow.
6(Low Speed):Turn the band away from you to
the rst solid band past the delay settings, for steady
wiping at low speed.
?(High Speed):Turn the band further, to the
second solid band past the delay settings, for
high-speed wiping.
Rainsense™ II Wipers
If your vehicle has Rainsense™ II windshield wipers,
the moisture sensor is located next to the inside
rearview mirror and is mounted on the windshield. When
active, these sensors are able to detect moisture on
the windshield and automatically turn on the wipers.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.
Since different drivers have different setting preferences,
it is recommended that the mid-range setting (position 3)
be used initially. For more wipes, select the higher
settings; for fewer wipes, select the lower settings located
closer to the off position on the multifunction lever.
The rainsensor will automatically control the frequency
of the wipes from the off setting to the high speed
setting according to the weather conditions. The wipers
can be left in a rainsense mode even when it is not
raining.
When Rainsense™ is active, the headlamps will turn on
automatically if the exterior lamp control is in the
AUTO position and the wipers are active.
Notice:Going through an automatic car wash with
the wipers on can damage them. Turn the wipers
off when going through an automatic car wash.
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6(Floor):This mode directs most of the air to the
oor outlets, with some of the air directed to the
windshield, side window outlets, and second row oor
outlets. In this mode, the system will automatically select
outside air. Recirculation cannot be selected when in
Floor Mode.
The right knob can also be used to select defog or
defrost mode. For more information, see “Defogging and
Defrosting” later in this section.
By positioning the right knob between two modes, a
combination of those two modes is selected.
The air conditioning compressor will be on unless the
outside temperature is close to freezing.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob all the way counterclockwise to turn the
front system off.
?(Recirculation):Press this button to turn the
recirculation mode on. When the button is pressed, an
indicator light will come on.This mode keeps outside air from entering the vehicle.
It can be used to reduce outside air and prevent
odors from entering the vehicle. Recirculation may also
help cool the air inside the vehicle more quickly once
the temperature inside the vehicle is less than the
outside temperature.
The recirculation mode cannot be used with oor,
defrost, or defogging modes. If you try to select
recirculation in one of those modes, the indicator will
ash three times and turn off. The air conditioning
compressor will also come on when this mode is
activated. While in recirculation mode the windows may
fog when the weather is cold and damp. To clear the
fog, select either the defog or defrost mode and increase
the fan speed. Recirculation mode can be turned off
by pressing the button again, or turning off the engine.
AUX (Auxiliary):Pressing this button will turn the
rear heating and air conditioning on. SeeRear
Air Conditioning and Heating System on page 3-33or
Rear Air Conditioning and Heating System and
Electronic Climate Controls on page 3-35for more
information.
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Driver’s Side Temperature Control
The driver’s side temperature buttons are used to adjust
the temperature of the air coming through the system on
the driver’s side. The temperature can be adjusted even if
the system is turned off. This is possible since outside air
will always ow through the system as the vehicle is
moving forward unless it is set to recirculation mode. See
“Recirculation” later in this section.
Press the + or−buttons to increase or decrease the
cabin temperature. The driver side temperature display
will show the temperature setting decreasing or
increasing.
Passenger’s Side Temperature Control
The passenger’s temperature buttons can be used to
change the temperature of the air coming through
the system on the passenger’s side of the vehicle. The
temperature can be adjusted even if the system is
turned off. This is possible since outside air will always
ow through the system as the vehicle is moving
forward unless it is set to recirculation mode. See
“Recirculation” later in this section.Press the + or−buttons to increase or decrease the
cabin temperature. The passenger side display will show
the temperature setting decreasing or increasing.
The passenger’s temperature setting can be set to match
the driver’s temperature setting by pressing the PASS
button and turning off the PASS indicator. When the
passenger’s temperature setting is set different than the
driver’s setting, the indicator on the PASS button will
illuminate and both the driver’s side and passenger’s side
temperature displays will be shown.
Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature, the
air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will change to
show the current temperature(s) and AUTO will
be lit on the display. The current delivery mode and
fan speed will also be displayed for approximately
5 seconds.
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