2010 HUMMER H3 parking brake

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.

Driving and Operating 9-49
5. Simultaneously press andhold the Four-Wheel High and
Four-Wheel-Low Lock buttons
for 10 seconds. The Neutral light
will come on when the transfer
case shift to Neutral is complete.
6. Press and hold the regular brake pedal and shift the transmission
to R (Reverse), then shift the
transmission to D (Drive) for
an automatic transmission,
or 1 (First) for vehicles have a
manual transmission and then
let out the clutch. This is to
ensure the transfer case is in
Neutral. If not, repeat this
procedure starting at Step 3.
7. Turn the engine off. 8. Place the transmission shift
lever in P (Park) for an automatic
transmission, or 1 (First) for
vehicles that have a manual
transmission.
9. Turn the ignition to LOCK/OFF.
Shifting Out of Neutral
To shift out of Neutral:
1. Set the parking brake and apply the regular brake pedal.
2. Shift the transmission to N (Neutral) for an automatic
transmission, or press the clutch
pedal for vehicles that have a
manual transmission. Then turn
the ignition to ON/RUN but do
not start the engine. 3. Press the button for the
desired transfer case shift
position (Four-Wheel High,
Four-Wheel-High Lock or
Four-Wheel-Low Lock).
After the transfer case has
shifted out of Neutral the light
will go out.
4. Release the parking brake.
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.
5. You may start the engine and shift the transmission to the
desired position.

Driving and Operating 9-51
Parking Brake
The parking brake pedal is located
to the left of the regular brake pedal,
near the driver door.
To set the parking brake, hold the
regular brake pedal down, then
push the parking brake pedal down
to its fully-applied position.A chime will sound and the brake
warning light will flash when the
parking brake is applied and the
vehicle is moving at least 5 km/h
(3 mph) for at least three seconds.
See
Brake System Warning Light
on page 5‑14.
To release the parking brake, hold
the regular brake pedal down. Pull
the park brake release lever, located
above the parking brake pedal. Notice:
Driving with the parking
brake on can overheat the brake
system and cause premature
wear or damage to brake system
parts. Make sure that the parking
brake is fully released and the
brake warning light is off before
driving.
If you are towing a trailer and are
parking on a hill, see Trailer Towing
on page 9‑74.
Brake Assist
This vehicle has a brake assist
feature designed to assist the
driver in stopping or decreasing
vehicle speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement
the power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle.

Driving and Operating 9-57
Cruise Control
With cruise control, a speed of
about 40 km/h (25 mph) or more can
be maintained without keeping your
foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
9(Off): Turns the cruise control
system off.
R (On): Turns the cruise control the
system on.
S(Resume/Accelerate): Makes
the vehicle accelerate or resume to
a previously set speed.
rT (Set): Press this button to set
the speed.
Cruise control will not work if the
parking brake is set, or if the master
cylinder brake fluid level is low.
If the brakes are applied, the cruise
control shuts off.
{WARNING
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. So, do not use
the cruise control on winding
roads or in heavy traffic.
(Continued)
WARNING (Continued)
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.
The cruise control disengages, if the
vehicle has the Traction Control
System (TCS) and it begins to limit
wheel spin. See Traction Control
System (TCS)
on page 9‑52.
When road conditions allow the
cruise control to be safely used
again, it can be turned back on.

9-60 Driving and Operating
Ending Cruise Control
To turn off the cruise control, do
one of the following:
.Step lightly on the brake pedal.
.Move the cruise control switch
to
9.
.Lightly tap or press the clutch,
if the vehicle has a manual
transmission.
Erasing Speed Memory
The cruise control set speed
memory is erased, when the cruise
control or the ignition is turned off.
Object Detection
Systems
Rear Vision
Camera (RVC)
Vehicles with the rear vision camera
system are designed to help the
driver while the vehicle is backing
up. The area behind the vehicle is
displayed on the screen in the
inside rear view mirror. Read this
entire section before using the
camera system.
When the key is in the ON/RUN
position and the driver shifts the
vehicle into R (Reverse), the video
image appears from inside the rear
view mirror. Once the vehicle is
shifted out of R (Reverse), the
image disappears. The display may have a guideline
overlay that can help the driver align
the vehicle when backing into a
parking spot.
Turning the Rear Vision Camera
System On or Off
To turn off the rear vision camera
system, press and hold
z, located
on the inside rearview mirror, until
the left indicator light turns off. The
rear camera vision display is now
disabled.
To turn the rear vision camera
system on again, press and
hold
zuntil the left indicator light
illuminates. The rear vision camera
system display is now enabled and
the display will appear in the mirror
normally.

Driving and Operating 9-73
Vehicles with an automatic
transmission 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. For vehicles with a
manual transmission, it is better not
to use the highest gear.
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. For vehicles with manualtransmissions, let the engine run
while parked, preferably on level
ground, with the transmission out of
gear and the parking brake applied,
for a few minutes before turning the
engine off. If the overheat warning
comes on, see
Engine Overheating
on page 10‑22.
Parking on Hills
{WARNING
Parking the vehicle on a hill
with the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface. If parking the rig on a hill:
1. Press the brake pedal, but do
not shift into P (Park) yet for
vehicles with an automatic
transmission, or into gear
for vehicles with a manual
transmission. Turn the wheels
into the curb if facing downhill
or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park) for vehicles with an
automatic transmission or into
gear for vehicles with a manual
transmission.
5. Release the brake pedal.

9-74 Driving and Operating
Leaving After Parking on a Hill
1. Apply and hold the brake pedalwhile you:
.start the engine,
.shift into a gear, and
.release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule
or Index for more information.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle lubricant, belts, cooling system and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
on page 10‑22.
Trailer Towing
Three important considerations
have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The total weight on the vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be?
Speed, altitude, road grades,
outside temperature, special
equipment, and the amount of
tongue weight the vehicle can carry
must be considered. See “Weight of
the Trailer Tongue” later in this
section for more information.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the
required trailering equipment.
The weight of additional optional
equipment, passengers and cargo in
the tow vehicle must be subtracted
from the maximum trailer weight.
Use the following chart to determine
how much a vehicle can weigh,
based on the vehicle model and
options.

Vehicle Care 10-13
Notice:Too much or too
little fluid can damage the
transmission. Too much can
mean that some of the fluid could
come out and fall on hot engine
parts or exhaust system parts,
starting a fire. Too little fluid
could cause the transmission to
overheat. Be sure to get an
accurate reading if checking the
transmission fluid.
Wait at least 30 minutes before
checking the transmission fluid level
if you have been driving:
.When outside temperatures are
above 32°C (90°F).
.At high speed for quite a while.
.In heavy traffic —especially in
hot weather.
.While pulling a trailer.
To get the right reading, the fluid
should be at normal operating
temperature, which is 82°C to 93°C
(180°F to 200°F). Get the vehicle warmed up by
driving about 24 km (15 miles) when
outside temperatures are above
10°C (50°F). If it is colder than 10°C
(50°F), drive the vehicle in 3 (Third)
until the engine temperature gauge
moves and then remains steady for
10 minutes.
A cold fluid check can be made
after the vehicle has been sitting
for eight hours or more with the
engine off, but this is used only
as a reference. Let the engine run
at idle for five minutes if outside
temperatures are 10°C (50°F) or
more. If it is colder than 10°C
(50°F), the engine might have to
idle longer. Should the fluid level be
low during this cold check, check
the fluid hot before adding fluid.
Checking the fluid hot gives a more
accurate reading of the fluid level.
Checking the Fluid Level
To prepare the vehicle:
1. Park the vehicle on a level
place. Keep the engine running.
2. With the parking brake applied, place the shift lever in P (Park).
3. With your foot on the brake pedal, move the shift lever
through each gear range,
pausing for about three seconds
in each range. Then, position the
shift lever in P (Park).
4. Let the engine run at idle for three minutes or more.