2009 HUMMER H2 heating

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 also be turned off by turning
off the ignition.
;(Outside Air, If Equipped):Press to turn on the
outside air mode. An indicator light comes on to show that
outside air is on. Air from outside is circulated throughout
the vehicle. The outside air mode can be used with all
modes, but it cannot be used with the recirculation mode.
REAR:For vehicles with the rear heat and air
conditioning controls. Press to turn the rear climate
control system on or off. SeeRear Air Conditioning
and Heating System and Electronic Climate Controls
on page 3-28.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press to turn the rear
window defogger on or off. It automatically turns off
several minutes after it has been activated. The defogger
can also be turned off by turning off the engine. Do not
drive the vehicle until all the windows are clear.
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.
Heated Mirrors:For vehicles with heated outside
rearview mirrors, the mirrors heat to help clear fog or
frost from the surface of the mirror when the rear window
defog button is pressed. SeeOutside Heated Mirrors
on page 2-49.
3-26

Operation Tips

Keep the hood and front air inlets free of ice,
snow, or any other obstruction, such as leaves.
The heater and defroster will work better, reducing
the chance of fogging the inside of the windows.
Keep the air path under the front seats clear of
objects. This helps air to circulate throughout
the vehicle.
Adding outside equipment to the front of the
vehicle, such as hood-air deectors, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer/retailer before
adding equipment to the outside of the vehicle.
Rear Air Conditioning and Heating
System and Electronic Climate
Controls
For vehicles with the rear heat and air conditioning
controls, they are integrated with the rear seat audio
controls located in the center console. The system can
be controlled from the front controls as well as the
rear controls.A. Fan Control
B. Air Delivery Mode Control
C. Temperature Control
REAR:Press the REAR button on the front climate
control system to turn the rear climate control system on
or off. An indicator comes on when the rear system is on.
The airow direction, temperature, and speed for the rear
of the vehicle will be the same as those set for the front of
the vehicle.
The rear controls can be used to control the air ow for
the rear of the vehicle separately from that of the front of
the vehicle. To turn the system on from the rear seats,
press any rear climate control button, except the
C
button. The rear climate control system can also be
turned off by pressing and holding the
Cbutton. Rear Climate Control with Rear Seat Audio Controls
3-28

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage
reads 210°F (100°C) or less. If the vehicle is pulling a
load or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-33.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when
the engine is started.
It provides information about tire pressures and the
Tire Pressure Monitoring System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDIC
Warnings and Messages on page 3-56for more
information. Stop and check the tires as soon as it is
safe to do so. If a tire is underinated, inate to the
proper pressure. SeeTires on page 5-57for more
information. United States
Canada
3-39

CHECK TIRE PRESSURE
On vehicles with the Tire Pressure Monitor
System (TPMS), this message displays when the
pressure in one or more of the vehicle’s tires needs to
be checked. This message also displays LEFT FRONT,
RIGHT FRONT, LEFT REAR, or RIGHT REAR to
indicate which tire needs to be checked. You can receive
more than one tire pressure message at a time. To read
the other messages that may have been sent at the same
time, press the set/reset button or the trip odometer reset
stem. If a tire pressure message appears on the DIC,
stop as soon as you can. Have the tire pressures
checked and set to those shown on the Tire Loading
Information label. SeeTires on page 5-57,Loading the
Vehicle on page 4-44, andInflation - Tire Pressure on
page 5-63. The DIC also shows the tire pressure values.
See “DIC Operation and Displays (Using DIC Buttons)”
earlier in this section. If the tire pressure is low, the low
tire pressure warning light comes on. SeeTire Pressure
Light on page 3-39.
DRIVER DOOR OPEN
This message displays and a chime sounds if the driver
door is not fully closed and the vehicle is shifted out
of P (Park). Stop and turn off the vehicle, check the
door for obstructions, and close the door again.
Check to see if the message still appears on the DIC.
ENGINE HOT A/C (Air Conditioning)
TURNED OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-39.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off.
When the coolant temperature returns to normal,
the air conditioning compressor turns back on.
You can continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible
to avoid damage to the engine.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. SeeEngine Overheating on page 5-33
for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle
to idle until it cools down. SeeEngine Coolant
Temperature Gage on page 3-39.
SeeOverheated Engine Protection Operating Mode on
page 5-35for information on driving to a safe place
in an emergency.
3-57

ENGINE POWER IS REDUCED
This message displays and a chime sounds when the
cooling system temperature gets too hot and the engine
further enters the engine coolant protection mode.
SeeEngine Overheating on page 5-33for further
information.
This message also displays when the vehicle’s engine
power is reduced. Reduced engine power can affect the
vehicle’s ability to accelerate. If this message is on, but
there is no reduction in performance, proceed to your
destination. The performance may be reduced the next
time the vehicle is driven. The vehicle may be driven at a
reduced speed while this message is on, but acceleration
and speed may be reduced. Anytime this message stays
on, the vehicle should be taken to your dealer/retailer for
service as soon as possible.
FUEL LEVEL LOW
This message displays and a chime sounds if the fuel
level is low. Refuel as soon as possible. SeeFuel Gage
on page 3-45andFuel on page 5-5for more information.
HEATED WASHER FLUID SYSTEM OFF
This message displays when the heated windshield
washer has been turned off. SeeWindshield Washer
on page 3-10for more information.
HEATING WASH FLUID WASH WIPES
PENDING
This message displays when the heated windshield
washer system is heating the uid. SeeWindshield
Washer on page 3-10for more information.
HOOD OPEN
This message displays and a chime sounds if the hood
is not fully closed. Stop and turn off the vehicle, check the
hood for obstructions, and close the hood again. Check to
see if the message still appears on the DIC.
ICE POSSIBLE DRIVE WITH CARE
This message displays when ice conditions are possible.
LEFT REAR DOOR OPEN
This message displays and a chime sounds if the driver
side rear door is not fully closed and the vehicle is shifted
out of P (Park). Stop and turn off the vehicle, check the
door for obstructions, and close the door again. Check to
see if the message still appears on the DIC.
3-58

TRACTION CONTROL OFF
This message displays when you turn off the Traction
Control System (TCS) or when the TCS has been
automatically disabled. Adjust your driving accordingly.
SeeTraction Control System (TCS) on page 4-9
andStabiliTrak
®System on page 4-6for more
information.
TCS may be automatically disabled due to overheating,
which could occur if the TCS activates continuously
for an extended period of time.
TRANSMISSION HOT IDLE ENGINE
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed
on the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead to
costly repairs that would not be covered by your
warranty. Do not drive your vehicle with overheated
transmission uid or while the transmission
temperature warning is displayed.This message displays along with a continuous chime
if the transmission uid in the vehicle gets hot. Driving
with the transmission uid temperature high can cause
damage to the vehicle. Stop the vehicle and let it idle to
allow the transmission to cool. This message clears and
the chime stops when the uid temperature reaches a
safe level.
TURN SIGNAL ON
This message displays and a chime sounds if a turn
signal is left on for 3/4 of a mile (1.2 km). Move the turn
signal/multifunction lever to the off position.
WASHER FLUID LOW ADD FLUID
This message displays when the windshield washer uid
is low. Fill the windshield washer uid reservoir as soon
as possible. SeeEngine Compartment Overview on
page 5-14for the location of the windshield washer
uid reservoir. Also, seeWindshield Washer Fluid
on page 5-37for more information.
3-63

Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on the instrument panel ash whenever
signaling a turn or lane change. Properly hooked up, the
trailer lamps also ash, telling other drivers the vehicle
is turning, changing lanes or stopping.
When towing a trailer, the arrows on the instrument panel
ash for turns even if the bulbs on the trailer are burned
out. For this reason you may think other drivers are
seeing the signal when they are not. It is important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbeforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might have to be used so
much that they would get hot and no longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
The tow/haul mode may be used if the transmission
shifts too often. SeeTow/Haul Mode Light on page 3-44.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If the engine is
turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this, let the engine run while
parked, preferably on level ground, with the automatic
transmission in P (Park) for a few minutes before turning
the engine off. If the overheat warning comes on, see
Engine Overheating on page 5-33.
4-65

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
the Vehicle.................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-6
Additives.......................................................5-6
Fuel E85 (85% Ethanol)..................................5-7
Fuels in Foreign Countries...............................5-8
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-11
Hood Release..............................................5-12
Engine Compartment Overview.......................5-14
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-23
Cooling System............................................5-27
Engine Coolant.............................................5-31
Engine Overheating.......................................5-33Overheated Engine Protection
Operating Mode.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-51
Front Turn Signal and Parking Lamps..............5-52
Daytime Running Lamps (DRL).......................5-52
Roof Marker Lamps......................................5-53
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-54
Replacement Bulbs.......................................5-55
Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-57
Tire Sidewall Labeling...................................5-58
Tire Terminology and Denitions.....................5-60
Ination - Tire Pressure.................................5-63
Tire Pressure Monitor System.........................5-64
Section 5 Service and Appearance Care
5-1