2010 HUMMER H3 warning

9-38 Driving and Operating
Leaving Your Vehicle With the
Engine Running (Automatic
Transmission)
{WARNING
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set. And, if you leave the
vehicle with the engine running, it
could overheat and even catch
fire. You or others could be
injured. Do not leave the vehicle
with the engine running.If you have to leave the vehicle with
the engine running, be sure the
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you have moved
the shift lever into P (Park), hold
the regular brake pedal down.
Then, see if you can move the shift
lever away from P (Park) without
first pressing the shift lever button.
If you can, it means that the shift
lever was not fully locked into
P (Park).
Torque lock is when the weight
of the vehicle puts too much
force on the parking pawl in the
transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not
done properly and then it is difficult
to shift out of P (Park). To prevent
torque lock, set the parking brake
and then shift into P (Park). To find
out how, see
“Shifting Into P (Park)”
listed previously. If torque lock does occur, your
vehicle may need to be pushed
uphill by another vehicle to relieve
the parking pawl pressure, so you
can shift out of P (Park).Shifting Out of Park
This vehicle is equipped with an
electronic shift lock release system.
The shift lock release is
designed to:
.Prevent ignition key removal
unless the shift lever is in
P (Park) with the shift lever
button fully released, and
.Prevent movement of the shift
lever out of P (Park) unless
the ignition is in ON/RUN or
ACC/ACCESSORY and the
regular brake pedal is applied.

9-40 Driving and Operating
Parking Over Things
That Burn
{WARNING
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.
Engine Exhaust
{WARNING
Engine exhaust contains Carbon
Monoxide (CO) which cannot be
seen or smelled. Exposure to CO
can cause unconsciousness and
even death.
Exhaust may enter the vehicle if:
.The vehicle idles in areas
with poor ventilation (parking
garages, tunnels, deep snow
that may block underbody
airflow or tail pipes).
.The exhaust smells or
sounds strange or different.
.The exhaust system leaks
due to corrosion or damage.(Continued)
WARNING (Continued)
.The vehicle’s exhaust system
has been modified, damaged
or improperly repaired.
.There are holes or openings
in the vehicle body from
damage or after-market
modifications that are not
completely sealed.
If unusual fumes are detected or
if it is suspected that exhaust is
coming into the vehicle:
.Drive it only with the windows
completely down.
.Have the vehicle repaired
immediately.
Never park the vehicle with the
engine running in an enclosed
area such as a garage or a
building that has no fresh air
ventilation.

Driving and Operating 9-41
Running the Vehicle
While Parked
It is better not to park with the
engine running. But if you ever have
to, here are some things to know.
{WARNING
Idling a vehicle in an enclosed
area with poor ventilation is
dangerous. Engine exhaust may
enter the vehicle. Engine exhaust
contains Carbon Monoxide (CO)
which cannot be seen or smelled.
It can cause unconsciousness
and even death. Never run the
engine in an enclosed area that
has no fresh air ventilation. For
more information, seeEngine
Exhaust on page 9‑40.
{WARNING
It can be dangerous to get out
of the vehicle if the automatic
transmission shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when
the engine is running unless you
have to. If you have left the
engine running, the vehicle can
move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
it is on fairly level ground, always
set the parking brake and move
the automatic transmission shift
lever to P (Park), or the manual
transmission shift lever to Neutral.
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park
on page 9‑37and Parking on page 9‑39.
If pulling a trailer, see Driving
Characteristics and Towing Tips
on
page 9‑70.
Automatic
Transmission
The automatic transmission has a
shift lever on the console.

9-42 Driving and Operating
It features an electronic shift
position indicator within the
instrument cluster.
There are several different positions
for the shift lever.
P (Park):This position locks the
rear wheels. It is the best position
to use when you start the engine
because the vehicle cannot move
easily.
{WARNING
It is dangerous to get out of the
vehicle if the shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when
the engine is running unless you
have to. If you have left the
engine running, the vehicle can
move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
you are on fairly level ground,
always set the parking brake and
move the shift lever to P (Park).
See Shifting Into Park
on
page 9‑37
. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑70. Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system. You must fully apply the
regular brakes first and then press
the shift lever button before you can
shift from P (Park) when the ignition
key is in ON/RUN. If you cannot
shift out of P (Park), ease pressure
on the shift lever and push the shift
lever all the way into P (Park) as
you maintain brake application.
Then press the shift lever button
and move the shift lever into
another gear. See
Shifting Out of
Park on page 9‑38.
R (Reverse): Use this gear to
back up.
Notice: Shifting to R (Reverse)
while the vehicle is moving
forward could damage the
transmission. The repairs would
not be covered by the vehicle
warranty. Shift to R (Reverse) only
after the vehicle is stopped.

Driving and Operating 9-43
To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see
If the Vehicle is Stuck on page 9‑26.
N (Neutral):In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only.
{WARNING
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed. Notice:
Shifting out of P (Park)
or N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:.Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down. Downshifting the transmission in
slippery road conditions could result
in skidding, see
“Skidding”under
Loss of Control on page 9‑6.
D (Drive) can be used when towing
a trailer. You may want to shift
the transmission to 3 (Third) or,
if necessary, a lower gear if the
transmission shifts too often under
heavy loads or in hilly conditions.
3 (Third): This position is also
used for normal driving. However it
reduces vehicle speed more than
D (Drive) without using the brakes.
You might choose 3 (Third) instead
of D (Drive) when driving on hilly or
winding roads, or when towing a
trailer, so there is less shifting
between gears, or when going down
a steep hill.

9-46 Driving and Operating
Shift Speeds
{WARNING
If you skip a gear when you
downshift, you could lose control
of the vehicle. You could injure
yourself or others. Do not shift
down more than one gear at a
time when you downshift.
Hill Start Assist
H3 and H3T vehicles have a Hill
Start Assist feature, which may be
useful when stopped on a grade.
SeeBraking
on page 9‑3for more
information.
Drive Systems
Four-Wheel Drive
Full-Time Four-Wheel Drive sends
engine power to all four wheels for
extra traction. To get the most out of
Full-Time Four-Wheel Drive, you
must be familiar with its operation.
Transfer Case Buttons
The transfer case buttons are
located to the right of the instrument
panel cluster. Use these switches
to shift into and out of the different
Full-Time Four-Wheel Drive modes. 4
m(Four-Wheel High):
This
setting is used for driving in most
street and highway situations. You
can also use this setting for light or
variable off-road conditions.
N (Neutral): Shift the transfer case
to Neutral only when towing the
vehicle. See Driving Characteristics
and Towing Tips
on page 9‑70for
more information.
Notice: Driving on pavement
in Four-Wheel High Lock or
Four Wheel Low Lock for
extended periods may cause
premature wear on the vehicle
powertrain and tires. Do not
drive in Four-Wheel High Lock
or Four-Wheel Low Lock on
pavement for extended periods.
4
m Q(Four-Wheel-High Lock):
Use this setting when you need
extra traction in most off-road
situations such as sand, mud,
snow or level, rocky trails.

9-48 Driving and Operating
If the Four-Wheel-Low Lock button
is pressed when the vehicle is in
gear and/or moving too fast, the
Four-Wheel-Low Lock indicator light
will flash for 15 seconds and not
complete the shift.
Shifting Out of
Four-Wheel-Low Lock
Notice:Shifting the transmission
into gear before the indicator
light stops flashing could cause
damage to the transfer case.
Always wait until the indicator
light stops flashing before putting
the transmission back in gear.
To shift out of Four-Wheel-Low
Lock, the vehicle must be stopped
or moving less than 5 km/h (3 mph)
with the transmission in N (Neutral)
and the ignition in ON/RUN. The
preferred method for shifting out of
Four-Wheel-Low Lock is to have
the vehicle moving 1.6 to 3.2 km/h
(1 to 2 mph). Press and release
the Four-Wheel High or
Four-Wheel-High Lock button. If the vehicle has a manual
transmission, the clutch pedal
must be pressed to the floor while
you press the Four-Wheel High
or Four-Wheel-High Lock button,
or the shift will not be completed.
You must wait for the Four-Wheel
High or Four-Wheel-High Lock
indicator light to stop flashing
and remain lit before shifting the
transmission into gear.
It is normal for the vehicle to have
engagement noise and bump when
shifting between Four-Wheel Low
and Four-Wheel High ranges or
from Neutral.
If the Four-Wheel High or
Four-Wheel-High Lock button is
pressed when the vehicle is in
gear and/or moving too fast,
the Four-Wheel High or
Four-Wheel-High Lock indicator
light will flash for 15 seconds
but will not complete the shift.
Shifting Into Neutral
To shift the transfer case to Neutral:
1. Set the parking brake.
2. Start the vehicle.
3. Put the transmission in
N (Neutral). If the vehicle has a
manual transmission, press and
hold the clutch pedal down while
you perform Steps 5 through 9.
4. Shift the transfer case to Four-Wheel High.
{WARNING
Shifting an all-wheel-drive
vehicle's transfer case into
Neutral can cause the vehicle
to roll even if the automatic
transmission is in P (Park) or the
manual transmission is in any
gear. You or others could be
injured. Make sure the parking
brake is firmly set before you shift
the transfer case to Neutral.

9-50 Driving and Operating
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the engine is started and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑15. If driving safely on a wet road and
it becomes necessary to slam on
the brakes and continue braking
to avoid a sudden obstacle, a
computer senses that the wheels
are slowing down. If one of the
wheels is about to stop rolling, the
computer will separately work the
brakes at each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. The ABS pump or motor
might be heard operating, and the
brake pedal might be felt to pulsate,
but this is normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.