2008 GMC SIERRA ECO mode

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.
Windshield Washer
{CAUTION:
In freezing weather, do not use your washer
until the windshield is warmed. Otherwise the
washer uid can form ice on the windshield,
blocking your vision.
L(Washer Fluid):Push the paddle marked with the
windshield washer symbol at the top of the multifunction
lever, to spray washer uid on the windshield. The
wipers clear the window and then either stop or return
to the preset speed.
Heated Windshield Washer
For vehicles with the heated windshield washer uid
system it can be used to help clear ice, snow, tree sap,
or bugs from your windshield.
The button is located in
the switchbank under the
climate controls.
Push the heated washer uid button to activate the
heated windshield washer uid system. The indicator
light will ash. This activation initiates four heated
wash/wipe cycles. The rst heated wash/wipe cycle may
take up to 40 seconds to occur, depending on outside
temperature. After the rst wash/wipe cycle, it may take
up to 20 seconds for each of the remaining cycles to
begin. Press the button again to turn off the heated
windshield washer uid system or it will automatically
turn off after four wipe cycles have been completed.
When the heated windshield washer uid system
is activated under certain outside temperature
conditions, steam may ow out of the washer nozzles
for a short period of time before washer uid is sprayed.
This is a normal condition.
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Use the right knob to select from the following modes:
The right knob can be positioned between two modes to
select a combination of those two modes.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs half of the air to the
instrument panel outlets and to the oor outlets.
6(Floor):This mode directs most of the air to the
oor outlets with some air directed to the windshield,
side window outlets, and second row oor outlets. In this
mode, the system will automatically select outside air.
Defogging and Defrosting
Fog or frost on the inside of windows is a result of high
humidity (moisture) condensing on the cool window
glass. This can be minimized if the climate control
system is used properly.
Turn the right knob to select the defog or defrost mode.
-(Defog):This mode clears the windows of fog or
moisture and warm the passengers. The air is directed to
the windshield, oor outlets, and side window vents.
0(Defrost):This mode removes fog or frost from the
windshield more quickly. A portion of the air is directed
to the windshield and the side window vents, with someair directed to the oor vents. The system will
automatically force outside air into the vehicle.
Do not drive the vehicle until all the windows are clear.
Dual Automatic Climate Control
System
The heating, cooling, and ventilation in the vehicle can
be controlled with this system. The vehicle also has
a ow-through ventilation system described later in this
section.
Different climate control settings can be selected for the
driver and passengers.
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Driver and Passenger Side Temperature
Controls
The driver and passenger side temperature buttons are
used to adjust the temperature of the air coming
through the system on the driver or passenger’s side of
the vehicle. The temperature can be adjusted even if
the system is turned off. This is possible since outside
air always ows 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 or passenger
side temperature display shows 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 illuminates and both the driver’s side and
passenger’s side temperature displays are shown.
Automatic Operation
AUTO (Automatic):When automatic operation is
active the system controls 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 changes to
show the current temperature(s) and AUTO is lit on
the display. The current air delivery mode and
fan speed are also displayed for about 5 seconds.
When AUTO is selected, the air conditioning
operation and air inlet are automatically controlled.
The air conditioning compressor may run when
the outside temperature is above freezing. The air
inlet will normally be set to outside air. If it is
hot outside, the air inlet may automatically switch to
the recirculate mode to help quickly cool down
the air inside the vehicle. The light on the button
comes on in recirculation.
2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F (23°C)
temperature setting and allow about 20 minutes
for the system to regulate. Use the driver’s or
passenger’s temperature buttons to adjust the
temperature setting as necessary. If you choose the
temperature setting of 60°F (15°C), the system
remains at the maximum cooling setting. If
you choose the temperature setting of 90°F (32°C),
the system remains at the maximum heat setting.
Choosing either maximum setting will not cause the
vehicle to heat or cool any faster.
3-29

)(Bi-Level):Air is directed partly to the instrument
panel outlets and to the oor outlets. A little air is
directed towards the windshield and side window outlets.
Cooler air is directed to the upper outlets and warmer
air to the oor outlets.
6(Floor):Air is directed to the oor outlets, with
some to the windshield, side window outlets, and
second row oor outlets. In this mode, the system will
automatically select outside air.
-(Defog):See “Defogging and Defrosting” later in
this section.
@(Recirculation):Press this button to turn the
recirculation mode on. When the button is pressed, an
indicator light comes 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, defog,
or defrost modes. If recirculation is selected with one
of those modes, the indicator light ashes three
times and then turns off. The air conditioning
compressor also comes 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.
The recirculation mode can be turned off by pressing
the outside air button, or by turning off the ignition.
;(Outside Air):Press this button to turn on
the outside air mode. When this mode is selected, air
from outside the vehicle circulates throughout the
vehicle. An indicator light on the button comes on to
show that it is activated. The outside air mode can be
used with all modes, but it cannot be used with the
recirculation mode.
Air Conditioning
#
(Air Conditioning):Press this button to turn the
air conditioning (A/C) compressor on and off. When
air conditioning is selected, an indicator light comes on
to show that the air conditioning has been activated.
Pressing this button when the outside temperature is too
cool for air conditioning makes the air conditioning
indicator ash three times and then turn off to let you
know the air conditioning mode is not available. If the air
conditioning is on and the outside temperature drops
below a temperature which is too cool for air conditioning
to be effective, the air conditioning light turns off to show
that the air conditioning mode has been canceled.
3-31

Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
Engine Hour Meter Display
The Driver Information Center (DIC) can also display
the number of hours the engine has run. To display the
engine hours, turn the ignition off, press and hold the
reset button for at least four seconds. The hour
meter will be displayed for up to 30 seconds, or until the
ignition is turned on. SeeDIC Operation and Displays
(With DIC Buttons) on page 3-55orDIC Operation
and Displays (Without DIC Buttons) on page 3-60for
more information.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the reset button, located on the instrument panel
cluster next to the voltmeter, to toggle between the
trip odometer and the regular odometer. Holding
the reset button for approximately one second while the
trip odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
SeeDIC Operation and Displays (With DIC Buttons) on
page 3-55orDIC Operation and Displays (Without
DIC Buttons) on page 3-60for more information.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm). See “Grade Braking
(Allison Transmission
®)” underTow/Haul Mode on
page 2-34for more information.
3-36

Charging System Light
This light will come on
briey when you turn on
the ignition, but the engine
is not running, as a
check to show you it is
working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-63
for more information. This light could indicate that you
have problems with a generator drive belt, or another
electrical problem. Have it checked right away. If
you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
Voltmeter Gage
Your vehicle may have a
voltmeter gage.
When the ignition is on, this gage indicates the battery
voltage.
When the engine is running, this gage shows the
condition of the charging system. The gage may
transition from a higher to lower or a lower to higher
reading, this is normal. If the vehicle is operating outside
the normal operating range, the charging system light
will come on. SeeCharging System Light on page 3-43
for more information. The voltmeter gage may also
read lower when in fuel economy mode. This is normal.
3-43

Transmission Temperature
Press the trip/fuel button until TRANS TEMP displays.
This display shows the temperature of the automatic
transmission uid in either degrees Fahrenheit (°F) or
degrees Celsius (°C).
Instantaneous Economy and Active Fuel
Management™ Indicator
If your vehicle has this display, press the trip/fuel button
until INST ECONOMY V8 MODE displays. This
display shows the current fuel economy at a particular
moment and will change frequently as driving conditions
change. This display shows the instantaneous fuel
economy in miles per gallon (mpg) or liters per
100 kilometers (L/100 km). Unlike average economy,
this screen cannot be reset.
An Active Fuel Management™ indicator will display on
the right side of the DIC, while INST ECONOMY
displays on the left side. Active Fuel Management™
allows the engine to operate on either four or eight
cylinders, depending on your driving demands. When
Active Fuel Management™ is active, V4 MODE will
display on the DIC. When Active Fuel Management™ is
inactive, V8 MODE will display. SeeActive Fuel
Management™ on page 2-27for more information.
Blank Display
This display shows no information.
Vehicle Information Menu Items
T
(Vehicle Information):Press this button to scroll
through the following menu items:
Oil Life
Press the vehicle information button until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-63. You should
change the oil as soon as you can. SeeEngine
Oil (Gasoline Engine) on page 5-15. In addition to the
engine oil life system monitoring the oil life, additional
maintenance is recommended in the Maintenance
Schedule in this manual. SeeScheduled Maintenance
(Gasoline Engine) on page 6-4for more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
3-58

Relearn Remote Key
This display allows you to match Remote Keyless Entry
(RKE) transmitters to your vehicle. To match an RKE
transmitter to your vehicle:
1. Press the vehicle information button until PRESS
V
TO RELEARN REMOTE KEY displays.
2. Press the set/reset button until REMOTE KEY
LEARNING ACTIVE is displayed.
3. Press and hold the lock and unlock buttons on the
rst transmitter at the same time for about
15 seconds.
On vehicles with memory recall seats, the rst
transmitter learned will match driver 1 and
the second will match driver 2.
A chime will sound indicating that the transmitter is
matched.
4. To match additional transmitters at this time, repeat
Step 3.
Each vehicle can have a maximum of eight
transmitters matched to it.
5. To exit the programming mode, you must cycle the
key to LOCK/OFF.
Blank Display
This display shows no information.
DIC Operation and Displays
(Without DIC Buttons)
If your vehicle does not have DIC buttons, the
information below explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the trip odometer reset stem located on the
instrument panel cluster. Pressing the trip odometer
reset stem will also turn off, or acknowledge, DIC
messages.
The DIC displays trip and vehicle system information,
and warning messages if a system problem is detected.
If your vehicle does not have DIC buttons, you can
use the trip odometer reset stem to view the following
displays: odometer, engine hours, trip odometer,
transmission temperature, trailer brake gain and output
information for vehicles with the Integrated Trailer
Brake Control (ITBC) system, oil life, Tire Pressure
Monitor System (TPMS) programming for vehicles with
the TPMS, Remote Keyless Entry (RKE) transmitter
programming, and display language.
If your vehicle has DIC buttons, you can use the
trip odometer reset stem to view the following
displays: odometer, engine hours, trip odometer, and
display language.
3-60