2008 HUMMER H2 engine

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
will remain at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C),
the system will remain at the maximum heat setting.
Choosing either maximum setting will not cause
the vehicle to heat or cool any faster.
Be careful not to cover the solar sensor located on
the top of the instrument panel near the windshield.
This sensor regulates air temperature based on sun load
and also turns on your headlamps. For more information
on the solar sensor, see “Sensors” later in this section.To avoid blowing cold air in cold weather, the system
will delay turning on the fan until warm air is available.
The length of delay depends on the engine coolant
temperature. Pressing the fan switch will override this
delay and change the fan to a selected speed.
O(On/Off):Press this button to turn off the climate
control system. Outside air will still enter the vehicle,
and will be directed to the oor. This direction can
be changed by pressing the mode button. Recirculation
can be selected once you have selected vent or
bi-level mode. The temperature can also be adjusted
using either temperature button. If you adjust the
air delivery mode or temperature settings with the
system off, the display will illuminate briey to show
you the settings and then return off. Press the on/off
button or the up down arrows on the fan switch,
the defrost button, AUTO button, or the air conditioning
button to turn the system on when it is off.
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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:For vehicles with the rear heat and air
conditioning controls. Press the AUX button to turn
the rear climate control system on or off. SeeRear
Air Conditioning and Heating System and Electronic
Climate Controls on page 3-29.
;(Outside Air, If Equipped):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 will make 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.
On hot days, open the windows long enough to let
hot inside air escape. This helps to reduce the time
it takes for your vehicle to cool down. It also helps the
system to operate more efficiently.
The air conditioning system removes moisture from the
air, so a small amount of water might drip underneath
the vehicle while idling or after turning off the engine.
This is normal.
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Defogging and Defrosting
Fog on the inside of the 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
clear fog or frost from the windshield.
Use the mode up and down arrows to select the
defog or defrost modes.
-(Defog):The defog mode is used to clear the
windows of fog or moisture and warm the passengers.
This mode directs air to the windshield, oor outlets,
and side window vents. When this mode is selected,
the system turns off recirculation and runs the air
conditioning compressor unless the outside temperature
is close to freezing. The recirculation mode cannot
be selected while in the defog mode. Do not drive
the vehicle until all the windows are clear.
0(Defrost):Press this button to remove fog or frost
from the windshield more quickly. This mode directs
a portion of the air to the windshield and side window
vents and some to the oor vents. In this mode, the
system will automatically force outside air into the
vehicle. The recirculation mode cannot be selected while
in the defrost mode. The air conditioning compressor
runs automatically in this setting, unless the outside
temperature is close to freezing. Do not drive the
vehicle until all the windows are clear.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press this button to
turn on the rear window defogger. It will automatically
turn off several minutes after it has been activated.
The defogger can also be turned off by pressing
the button again or by turning off the engine. Do not
drive the vehicle until all the windows are clear.
If your vehicle has heated outside rearview mirrors,
the mirrors will heat to help clear fog or frost from the
surface of the mirror when the rear window defog
button is pressed.
Notice:Do not use a razor blade or sharp object
to clear the inside rear window. Do not adhere
anything to the defogger grid lines in the rear glass.
These actions may damage the rear defogger.
Repairs would not be covered by your warranty.
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Warning Lights, Gages,
and Indicators
This part describes the warning lights and gages
on your vehicle. The pictures help to 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 the 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 the details show on the next few pages, some
warning lights come on briey when you start
the engine just to let you know they are 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 is a problem with your vehicle.
When one of the warning lights comes on and stays
on as 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 vehicle’s
warning lights and gages. They can be a big help.
Your vehicle also has a Driver Information Center (DIC)
that works along with warning lights and gages.
SeeDIC Warnings and Messages on page 3-56
for more information.
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Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your vehicle’s odometer works together with the
driver information center. You can set a Trip odometer.
See “Trip Odometer” underDIC Operation and
Displays (Using DIC Buttons) on page 3-49or
DIC Operation and Displays (Using Trip Odometer
Reset Stem) on page 3-54for more information.
The odometer mileage can be checked without the
vehicle running. Simply press the trip stem on the
instrument panel cluster.
If your vehicle ever 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.
Press the trip stem to toggle between the trip odometer
and the regular odometer. Holding the trip stem for
approximately one second while the trip odometer is
displayed will reset it.
To display the odometer reading with the ignition off,
press the trip stem.
Tachometer
Your 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.
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.
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Airbag Readiness Light
There is an airbag readiness light on the center
overhead console, 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
sensors, the airbag modules, the wiring and the crash
sensing and diagnostic module. For more information
on the airbag system, seeAirbag System on page 1-64.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
Then the light should
go out. This means
the system is ready.
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 the engine is started. If the light does not come
on then, have it xed so it will be ready to warn you if
there is a problem.
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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 3-56
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
When your engine is
not running, but the
ignition is on, this gage
shows the battery’s
state of charge in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery
for improved fuel economy and battery life. The gage
may transition from a higher to lower or a lower to
higher reading, this is normal. Readings between
the low and high warning zones indicate the normal
operating range. The gage may also read low during
the fuel economy mode, this is normal.
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Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left at an idle for
an extended period. This condition is normal since
the charging system is not able to provide full power
at engine idle. As engine speeds are increased,
this condition should correct itself as higher engine
speeds allow the charging system to create full power.
If there is a problem with the battery charging system,
this light will come on or the SERVICE BATTERY
CHARGING SYSTEM DIC message will display.
SeeDIC Warnings and Messages on page 3-56
andCharging System Light on page 3-37for
more information.
Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set the parking brake.
If you try to drive with the parking brake engaged,
a chime will sound when the vehicle speed is
greater than 5 mph (8 km/h).Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part
can still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
This light may also come on due to low brake uid.
SeeBrakes on page 5-36for more information.
This light should come on briey when you turn the
ignition key to RUN. If it does not come on then,
have it xed so it will be ready to warn you if there
is a problem.United StatesCanada
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