2008 GMC ENVOY engine

Driver’s Side Temperature Lever:The lever on the
left side of the climate control panel is used to raise
or lower the temperature on the driver’s side of
the vehicle. Slide the lever up or down to adjust
the temperature.
Passenger’s Side Temperature Lever:The lever on
the right side of the climate control panel is used to raise
or lower the temperature on the passenger’s side of
the vehicle. Slide the lever up or down to adjust the
temperature. This lever also adjusts the temperature
to the rear seat outlets.
When the temperature outside is 0°F (−18°C) or lower,
use the engine coolant heater, if the vehicle has
one, to provide warmer air, faster to your vehicle.
#(Air Conditioning):Press this button to turn the
air-conditioning system on or off. When the button is
pressed, an indicator light will come on and the system
will begin to cool and dehumidify the air inside of the
vehicle. You may notice a slight change in engine
performance when the air conditioning compressor
shuts off and turns on again. This is normal.
Defogging and Defrosting
Fog 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. There are two modes to choose from to clear
fog or frost from your windshield. Use the defog mode
to clear the windows of fog or moisture and warm the
passengers. Use the defrost mode to remove fog or
frost from the windshield more quickly.
Turn the right knob clockwise or counterclockwise to
select one of the following modes:
-(Defog):This mode directs the air to the
oor outlets, windshield and side window outlets.
The recirculation button cannot be selected while in
defog mode.
1(Defrost):This mode directs most of the air to the
windshield and the side window outlets, with only a little
air directed to the oor outlets. The air conditioning
compressor may run to dehumidify the air to prevent
window fogging. The recirculation button cannot be
selected while in defrost mode. Do not drive the vehicle
until all the windows are clear.
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9(Off):Press this button to turn off the entire climate
control system. Outside air will still enter the vehicle, and
will be directed to the oor. Press the AUTO button, the
mode button, the fan arrows, or either temperature knob
to turn the system on.
C(Mode):Press this button to manually select the air
delivery mode to the oor, instrument panel, or windshield
outlets. The system will stay in the selected mode until
the mode button is pressed again or the AUTO button is
pressed.
Driver’s Side Temperature Knob:Turn this knob
clockwise or counterclockwise to raise or lower the
temperature on the driver’s side of the vehicle. The
display will show the temperature setting decreasing
or increasing and an arrow pointing toward the driver.
This knob can also adjust the passenger’s side
temperature setting if the two are linked.Passenger’s Side Temperature Knob:Turn this
knob clockwise or counterclockwise to manually raise or
lower the temperature on the passenger’s side of the
vehicle. The display will show the temperature setting
decreasing or increasing and an arrow pointing toward
the passenger. The passenger’s temperature setting
can be set to match and link to the driver’s temperature
setting by pressing and holding the AUTO button for
three seconds. When adjusting the driver’s side
temperature setting, the passenger’s side temperature
setting will follow and both arrows will appear on the
display. The passenger’s side temperature setting also
resets and relinks to the driver’s side temperature setting
if the vehicle has been off for more than three hours.
Outside Air Temperature Display
A new outside temperature reading will be displayed
if the vehicle has been off for more than three hours.
If the vehicle has been off for less than three hours,
the old temperature reading may be displayed because
underhood heat is affecting the true outside temperature.
Underhood heat can also affect the outside temperature
while the engine is running. It may also take
several minutes of driving before the display
updates to the actual outside temperature.
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6(Floor):This mode directs most of the air to the
oor outlets. Some air also comes out of the defroster
and side window outlets. The recirculation button
cannot be selected in oor mode.
@(Recirculation):Press this button to turn
recirculation mode on or off. When this button is pressed,
an indicator light in the button will also come on to let you
know that it is activated. Recirculation mode is used to
recirculate the air inside of your vehicle. Use this mode to
help prevent outside odors and/or dust from entering your
vehicle or to help cool the air inside of your vehicle more
quickly. Recirculation mode can be used with vent and
bi-level modes, but it cannot be used with oor, defog or
defrost modes. Defog and defrost modes are described
later in this section.
If recirculation mode is selected with oor, defog, or
defrost modes, the indicator will ash three times and
then turn off indicating the selection is not available.
You may also notice that the air conditioning compressor
will run while in recirculation mode. This is normal and will
help to prevent fogging.
If the weather is cold and damp, the system may cause
the windows to fog while using recirculation mode. If the
windows do start to fog, select defog or defrost mode and
increase fan speed.
Recirculation mode, if selected, will be cleared when the
engine is turned off.
#A/C (Air Conditioning):Press this button to
manually turn the air conditioning system on or off.
When the system is on, the system will automatically
begin to cool and dehumidify the air inside of your
vehicle. The air conditioning symbol will appear on the
display when the air conditioning is on and will turn
off when the air conditioning is off.
If you turn the air conditioning off while in front defrost
or defog mode, the air conditioning symbol will turn
off, however, the A/C compressor will remain on to help
de-humidify the air inside the vehicle. If one of the
other modes is selected the compressor will then turn
the A/C off until it is selected again or the AUTO button
is pressed.
To avoid fogging the inside glass on rainy and humid
days at a temperature above freezing, press the air
conditioning button to run the A/C compressor. Also it is
best to avoid the use of the recirculation mode except
when maximum air conditioning performance is needed
or for short times to avoid exterior odors.
You may notice a slight change in engine performance
when the air-conditioning compressor shuts off and turns
on again. This is normal.
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Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something
is wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention
to your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you
will see in the details on the next few pages, some
warning lights come on briey when you start the engine
just to let you know they’re working. If you are familiar
with this section, you should not be alarmed when
this happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages and
warning lights work together to let you know when there’s
a problem with your vehicle.
When one of the warning lights comes on and stays
on when you are driving, or when one of the gages
shows there may be a problem, check the section
that tells you what to do about it. Please follow this
manual’s advice.
Waiting to do repairs can be costly—and even
dangerous. So please get to know your warning
lights and gages. They’re a big help.
Your vehicle may also have a Driver Information
Center (DIC) that works along with the warning lights
and gages. SeeDriver Information Center (DIC)
on page 3-49.
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Speedometer and Odometer
The speedometer lets you see your speed in both miles
per hour (mph) and kilometers per hour (km/h).
The odometer shows how far your vehicle has been
driven, in either miles (used in the United States)
or kilometers (used in Canada).
The odometer mileage can be checked without the
vehicle running. Press the trip stem located on
the instrument panel cluster.
If your vehicle needs a new odometer installed, the new
one will be set to the correct mileage total of the old
odometer.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
The odometer works together with the Driver Information
Center (DIC). You can set a Trip A and Trip B odometer.
See “Trip Information” underDIC Operation and Displays
on page 3-50.
The odometer mileage can be checked without the
vehicle running. Press the trip stem on the instrument
panel cluster.
Tachometer
The tachometer displays
the engine speed in
revolutions per
minute (rpm).
Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime will come on for
several seconds to remind people to fasten their safety
belts, unless the driver’s safety belt is already buckled.
The safety belt light will
also come on and stay on
for several seconds, then it
will ash for several more.
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This chime and light is repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s belt
is already buckled, neither the chime nor the light will
come on.
Passenger Safety Belt Reminder Light
Several seconds after the engine is started, a chime will
sound for several seconds to remind the front passenger
to buckle their safety belt. This would only occur if the
passenger airbag is enabled. SeePassenger Sensing
System on page 1-61for more information. The
passenger safety belt light, located on the instrument
panel, will come on and stay on for several seconds and
then ash for several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger’s safety belt is buckled, neither the
chime nor the light will come on.
Airbag Readiness Light
There is an airbag readiness light on the instrument panel
cluster, which shows the airbag symbol. The system
checks the airbag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the airbag sensor, the
pretensioners, the airbag modules, the wiring and
the crash sensing and diagnostic module. For more
information on the airbag system, seeAirbag System
on page 1-53.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds. The
light should go out and
the system is ready.
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If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your airbag
system may not work properly. Have your vehicle
serviced right away.
{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the airbag readiness light
stays on after you start your vehicle.
The airbag readiness light should ash for a few
seconds when you start the engine. If the light does
not come on then, have it xed immediately. If there
is a problem with the airbag system, an airbag Driver
Information Center (DIC) message may also come
on. SeeDIC Warnings and Messages on page 3-53for
more information.
Passenger Airbag Status Indicator
Your vehicle has the passenger sensing system.
Your rearview mirror has a passenger airbag status
indicator.
When you start the vehicle, the passenger airbag status
indicator will light ON and OFF, or the symbol for on
and off, for several seconds as a system check.United States
Canada
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If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may
be a problem with the lights or the passenger sensing
system. See your dealer/retailer for service.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on,
it means that something may be wrong with
the airbag system. If this ever happens, have
the vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger’s seat may not have the protection
of the airbag(s). SeeAirbag Readiness Light
on page 3-33for more on this, including
important safety information.
Charging System Light
This light will come on
briey when you turn on the
ignition key, 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 driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-53for
more information. This light could indicate that there
are problems with a generator drive belt, or that there is
an electrical problem. Have it checked right away. If you
must drive a short distance with the light on, be certain
to turn off all the accessories, such as the radio and air
conditioner.
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