cooling HUMMER H2 2006 Owners Manual

Liftgate (SUV)
{CAUTION:
It can be dangerous to drive with the liftgate
open because carbon monoxide (CO) gas can
come into your vehicle. You can not see or
smell CO. It can cause unconsciousness and
even death. If you must drive with the liftgate
open or if electrical wiring or other cable
connections must pass through the seal
between the body and the liftgate:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed and select the
control setting that will force outside air
into your vehicle. SeeDual Automatic
Climate Control System on page 3-22.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-37.
To lock and unlock the liftgate, use any of the power
door lock switches or the remote keyless entry (RKE)
transmitter.To open the liftgate, do the following:
1. Move the spare tire carrier out of the way. See
“Opening the Spare Tire Carrier” under
Tailgate/Spare Tire Carrier on page 2-14.
2. Pull the handle located in the center of the door.
To close the liftgate, do the following:
1. Pull the liftgate down until it latches.
2. Move the spare tire carrier back into place. See
“Closing the Spare Tire Carrier” under
Tailgate/Spare Tire Carrier on page 2-14.
2-11

Midgate®(SUT)
{CAUTION:
It can be dangerous to drive with the cargo
area covered and the tailgate and the midgate®
open because carbon monoxide (CO) gas can
come into your vehicle. You can not see or
smell CO. It can cause unconsciousness and
even death. If you must drive with the cargo
covers on and the tailgate and midgate
®open
or if electrical wiring or other cable
connections must pass through the seal
between the body and the midgate
®:
Make sure all windows are shut.Turn the fan on your heating or cooling
system to its highest speed on the setting
that brings in outside air. This will force
outside air into your vehicle. SeeDual
Automatic Climate Control System on
page 3-22.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-37.
The midgate
®allows you to extend the length of your
vehicle’s cargo area into the cab.
Lowering the Midgate®
The midgate®window must be completely lowered for
the midgate®to be lowered. See “Midgate®Window”
underPower Windows on page 2-18.
Both the midgate
®and the midgate®window can be
lowered while the ignition is in either RUN or
ACCESSORY, or while in Retained Accessory Power
(RAP) mode. SeeRetained Accessory Power (RAP) on
page 2-25for more information.
To lower the midgate
®, do the following:
1. Fold the rear seats forward. See60/40 Split Bench
Seat on page 1-6. The front seats may have to be
moved forward slightly.
2.
K(Midgate®Window):Press the bottom part of
this switch to lower the midgate®window. See
Instrument Panel Overview on page 3-4for
the location of this switch. The window can also be
operated using the global express-down button.
See “Global Glass Feature” underPower Windows
on page 2-18.
2-12

Ashtray(s) and Cigarette Lighter
If your vehicle has an ashtray, it is removable and ts
into the front cupholder. Pull up on the ashtray door
to open it.
Notice:If you put papers, pins, or other ammable
items in the ashtray, hot cigarettes or other
smoking materials could ignite them and possibly
damage your vehicle. Never put ammable items in
the ashtray.
To remove the ashtray, pull it out from the console. To
reinstall the ashtray, slide it back to the original position.
To use the cigarette lighter, if equipped, push it in all
the way, and let go. When it’s ready, it will pop back out
by itself.
Notice:Holding a cigarette lighter in while it is
heating will not allow the lighter to back away from
the heating element when it is hot. Damage from
overheating may occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating.
Climate Controls
Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle.
You can select different climate control settings for the
driver and passengers.
3-22

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 driver’s set temperature, delivery
mode and fan speed. Press the AUTO button again
within ve seconds to display the passenger’s set
temperature.
If the driver and passenger’s temperature
settings are not the same, the opposite side
temperature setting will be displayed for an
additional ve seconds. To make the passenger’s
temperature the same as the driver’s press and hold
the AUTO button for about four seconds.
When auto is selected, the air conditioning operation
and air inlet will be automatically controlled. The
air conditioning compressor will run when the
outside temperature is over about 40°F (4°C). The
air inlet will normally be set to outside air. If it’s
hot outside, the air inlet may automatically switch to
recirculate inside air to help quickly cool down
your vehicle. The light on the button will illuminate
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. Turn the driver’s orpassenger’s side temperature knob 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 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.
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.
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. This direction can be changed
by pressing the mode button. The temperature can also
be adjusted using either temperature knob. Press the up
or down arrows on the fan switch, the defrost button, the
AUTO button, or the air conditioning button to turn the
system on when it is off.
3-24

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are 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 5-27.
Transmission Temperature Gage
Your vehicle is equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the temperature
of the transmission uid. The normal operating range is
from 180°F (82°C) to about 200°F (93°C).
At approximately 265°F (130°C), the DIC will display a
TRANSMISSION HOT message and the transmission
will enter a transmission protection mode. When
the transmission enters the protection mode, you may
notice a change in the transmission shifting patterns.
The transmission will return to normal shifting patterns
when the transmission uid temperature falls below
260°F (127°C). United States
CanadaUnited StatesCanada
3-37

ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Turn off the air conditioning. If
the message is still on, or if the engine coolant
temperature gage continues to rise, pull the vehicle over
when it is safe to do so. SeeEngine Coolant
Temperature Gage on page 3-37for more information.
Stop the vehicle and let the engine idle in PARK (P)
for a few minutes to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to a safe operating
temperature. Pressing any of the four DIC buttons or
the trip odometer reset stem will clear the message from
the DIC display.
ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing any of the four DIC buttons or the
trip odometer reset stem will clear the message from the
DIC display. It will also clear itself after 10 seconds.
The low fuel light near the fuel gage will still remain on
in either case. SeeLow Fuel Warning Light on
page 3-44,Fuel Gage on page 3-44, andFuel on
page 5-5for more information.
KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. See “Battery
Replacement” underRemote Keyless Entry System
Operation on page 2-5. Pressing any of the
four DIC buttons or the trip odometer reset stem
will clear the message from the DIC display.
LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed and the
vehicle is in a drive gear, this message will appear
on the display and you will hear a chime. Stop and turn
off the vehicle, check the door for obstacles, and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons or the trip odometer reset stem will clear the
message from the DIC display.
3-50

OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message. SeeEngine Oil on page 5-14and “Engine Oil
Life System” underDIC Operation and Displays on
page 3-45for more information.
OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced by your dealer.
PASSENGER DOOR AJAR
If the passenger’s door is not fully closed and the
vehicle is in a drive gear, this message will appear on
the display and you will hear a chime. Stop and turn off
the vehicle, check the door for obstacles, and close
the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons or the trip odometer reset stem will clear the
message from the DIC display.
REAR ACCESS OPEN
On the SUV, if the liftgate is open while the ignition is in
RUN, this message will appear on the DIC and you
will hear a chime. Turn off the vehicle and check
the liftgate. Restart the vehicle and check for the
message on the DIC display. Pressing any of the
four DIC buttons or the trip odometer reset stem will
clear the message from the DIC display.
On the SUT, if the midgate is open or one or both of the
midgate latches are not fully closed, this message will
appear on the DIC. Turn off the vehicle and check that
the midgate and the latches are closed. Restart the
vehicle and check for the message on the DIC display.
Pressing any of the four DIC buttons or the trip odometer
reset stem will clear the message from the DIC display.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
SeeEngine Overheating on page 5-27for further
information.
You may also see this message when the vehicle
determines a problem with the electronic throttle control.
See your dealer for service.
3-51

Stalling on an Incline
If your vehicle stalls when you are crossing an incline,
be sure you, and any passengers, get out on the
uphill side, even if the door there is harder to open. If
you get out on the downhill side and the vehicle starts to
roll over, you will be right in its path.
If you have to walk down the slope, stay out of the path
the vehicle will take if it does roll over.{CAUTION:
Getting out on the downhill (low) side of a
vehicle stopped across an incline is
dangerous. If the vehicle rolls over, you could
be crushed or killed. Always get out on the
uphill (high) side of the vehicle and stay well
clear of the rollover path.
Driving in Mud, Sand, Snow, or Ice
When you drive in mud, snow, or sand, your wheels will
not get good traction. You cannot accelerate as quickly,
turning is more difficult, and you will need longer braking
distances.
It is best to use a low gear when you are in mud — the
deeper the mud, the lower the gear. In really deep
mud, the idea is to keep your vehicle moving so you do
not get stuck. Be careful to keep mud from building
up and washing onto the engine cooling system.
When you drive on sand, you will sense a change in
wheel traction. But it will depend upon how loosely
packed the sand is. On loosely packed sand, such as
on beaches or sand dunes, your tires will tend to
sink into the sand. This has an effect on steering,
accelerating, and braking. Drive at a reduced speed and
avoid sharp turns or abrupt maneuvers.
4-32

After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis, or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the engine and oil
coolers for mud accumulation. Thoroughly and carefully
clean these devices to allow proper cooling. Check
the body structure, steering, suspension, wheels, tires,
and exhaust system for damage. Also, check the
fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. See the Maintenance Schedule for
additional information.
Assist Steps
Your vehicle may be equipped with removable side steps.
Remove the steps prior to off-roading to give your
vehicle more ground clearance and to prevent damage
to the vehicle from the side steps dragging and/or
catching on obstacles.
Notice:Do not drive off-road with the side steps
attached to your vehicle. You can damage the side
steps and/or your vehicle’s frame if they get caught
or drag against an obstacle. This damage would not
be covered by your vehicle’s warranty. Always
remove the side steps prior to any off-road driving.
U-Type Side Steps
The following instructions show how to install the
optional U-type steps. If you want to remove them, just
reverse the instructions:
1. Start with the side step brackets pointing up and
away from you, or just make sure the HUMMER
logo faces up.
2. For the front step, use the rst and third brackets
on the vehicle from the front tire. For the rear step,
use the rst and third brackets on the vehicle
from the rear tire.
You will notice that the side steps have pins on
both sides of the step brackets. This is because the
steps are interchangeable between front/back
and the driver/passenger sides of the vehicle. Use
the pins as follows:
Driver Side:Look at the side step with the
HUMMER logo facing you. You will use the pins
which are on the right side of each side step
bracket. This works for the front or rear of
the vehicle.
Passenger Side:Look at the side step with the
HUMMER logo facing you. You will use the pins
which are on the left side of each side step
bracket. This works for the front or rear of
the vehicle.
4-34

Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. SeeOff-Road
Driving on page 4-16for information about driving
off-road.
Keep your vehicle in good shape. Check all uid
levels and also the brakes, tires, cooling system,
and transmission. These parts can work hard
on mountain roads.
{CAUTION:
If you do not shift down, your brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let your engine assist your brakes on a
steep downhill slope.
4-44