2009 HUMMER H2 light

Traction Control Operation
The traction control system is part of the
StabiliTrak system. Traction control limits wheel
spin by reducing engine power to the wheels (engine
speed management) and by applying brakes to
each individual wheel (brake-traction control) as
necessary.
The traction control system is enabled automatically
when the vehicle is started. It will activate and the
StabiliTrak light will ash if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If the traction control is turned off, only the
brake-traction control portion of traction control will work.
The engine speed management will be disabled. In this
mode, engine power is not reduced automatically and the
driven wheels can spin more freely. This can cause the
brake-traction control to activate constantly.
Notice:If the wheel(s) of one axle is allowed to
spin excessively while the StabiliTrak, ABS
and brake warning lights and any relevant DIC
messages are displayed, the transfer case could bedamaged. The repairs would not be covered by the
vehicle warranty. Reduce engine power and do
not spin the wheel(s) excessively while these lights
and messages are displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens, a reduction
in acceleration may be noticed, or a noise or vibration
may be heard. This is normal.
If cruise control is being used when StabiliTrak activates,
the cruise control automatically disengages. The
cruise control can be re-engaged when road conditions
allow. SeeCruise Control on page 3-12.
StabiliTrak may also turn off automatically if it determines
that a problem exists with the system. If the problem does
not clear itself after restarting the vehicle, see your
dealer/retailer for service.
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To turn the system off,
press and release the
TCS button.
This light will come on
steady when the traction
control system has been
turned off. This light ashes
when TCS is active.
If the TCS button is pressed, the traction control system
will turn off and a TRACTION CONTROL OFF message
will appear on the DIC. Press the TCS button again to
turn the system back on. The TRACTION CONTROL
OFF message will then go off. The Traction Control
System will reset itself at each ignition cycle.
Adding non-dealer/non-retailer accessories can affect
the vehicle’s performance. SeeAccessories and
Modifications on page 5-3.Locking Rear Axle
The locking rear axle can give the vehicle additional
traction from the rear wheels when traveling in off-road
situations such as mud, snow, sand, steep hills and
uneven terrain.
The button used to turn
this feature on or off is
located below the transfer
case dial to the right of
the steering wheel.
To lock the rear axle:
1. Place the transfer case in the Four-Wheel-Low Lock
mode. This is the only mode which will allow the rear
axle to lock. SeeFull-Time Four-Wheel Drive on
page 2-37for more information regarding the transfer
case and Four-Wheel-Low-Lock mode.
2. Press the button with the vehicle stopped or moving
less than 2 mph (3 km/h).
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The light in the button must stop ashing and remain
illuminated before the rear axle is locked.
Notice:If you try to lock the axle while the vehicle
is stuck and the tires are spinning, the vehicle’s
drivetrain could be damaged. The repairs would not
be covered by the vehicle warranty. Always lock
the axle before attempting situations and/or
navigating terrain which could possibly cause the
vehicle to become stuck.
The locking rear axle will be disengaged when the
vehicle’s speed is greater than 40 mph (64 km/h), if the
vehicle’s battery is low and/or the transfer case is
shifted out of Four-Wheel-Low-Lock mode.
Notice:If the vehicle’s axle is locked while driving
on pavement, the drivetrain could be damaged.
Repairs would not be covered by the vehicle
warranty. Do not use the locking axle on pavement.
If four-wheel drive is needed when traveling on
pavement, use only 4HI.Steering
Power Steering
If power steering assist is lost because the engine stops
or the system is not functioning, the vehicle can be
steered but it will take more effort.
Steering Tips
It is important to take curves at a reasonable speed.
Traction in a curve depends on the condition of the tires
and the road surface, the angle at which the curve is
banked, and vehicle speed. While in a curve, speed is
the one factor that can be controlled.
If there is a need to reduce speed, do it before entering
the curve, while the front wheels are straight.
Try to adjust the speed so you can drive through the
curve. Maintain a reasonable, steady speed. Wait
to accelerate until out of the curve, and then accelerate
gently into the straightaway.
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Off-Road Recovery
The vehicle’s right wheels can drop off the edge of a
road onto the shoulder while driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then, if there is nothing in the way, steer
so that the vehicle straddles the edge of the pavement.
Turn the steering wheel 3 to 5 inches, 8 to 13 cm,
(about one-eighth turn) until the right front tire contacts
the pavement edge. Then turn the steering wheel to go
straight down the roadway.
Passing
Passing another vehicle on a two-lane road can be
dangerous. To reduce the risk of danger while passing:
Look down the road, to the sides, and to crossroads
for situations that might affect a successful pass.
If in doubt, wait.
Watch for traffic signs, pavement markings, and
lines that could indicate a turn or an intersection.
Never cross a solid or double-solid line on your side
of the lane.
Do not get too close to the vehicle you want to
pass. Doing so can reduce your visibility.
Wait your turn to pass a slow vehicle.
When you are being passed, ease to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
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Off-Road Driving
The airbag system is designed to work properly under a
wide range of conditions, including off-road usage.
Always wear your safety belt and observe safe driving
speeds, especially on rough terrain.
Drinking and driving can be very dangerous on any road
and this is certainly true for off-road driving. At the very
time you need special alertness and driving skills, your
reexes, perceptions, and judgment can be affected
by even a small amount of alcohol. You could have a
serious — or even fatal — accident if you drink and drive
or ride with a driver who has been drinking.
Off-roading can be great fun but has some denite
hazards. The greatest of these is the terrain itself. When
off-road driving, traffic lanes are not marked, curves
are not banked, and there are no road signs. Surfaces
can be slippery, rough, uphill, or downhill.
Avoid sharp turns and abrupt maneuvers. Failure to
operate the vehicle correctly off-road could result in loss
of vehicle control or vehicle rollover.
Off-roading involves some new skills. That is why it is
very important that you read these driving tips and
suggestions to help make off-road driving safer
and more enjoyable.
Before You Go Off-Roading
Have all necessary maintenance and service
work done.
Make sure there is enough fuel, that uid levels are
where they should be, and that the spare tire is fully
inated.
Be sure to read all the information about
four-wheel-drive vehicles in this manual.
Make sure any equipment you may need — rst aid
kit, cell phone, ashlight, etc. — is securely stored
in the vehicle.
Remove any removable side steps. SeeAssist
Steps on page 4-33.
Make sure all underbody shields, if the vehicle has
them, are properly attached.
Know the local laws that apply to off-roading where
you will be driving or check with law enforcement
people in the area.
Be sure to get the necessary permission if you will
be on private land.
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Brake and Accelerator Operation
Techniques for Off-Road Driving
For logs, walls, rocks, severe ditches,
hills, sand, etc.
1. Bring the vehicle to a complete stop. Do not rev the
engine.
2. Select the proper transmission and transfer case
gear range; usually 1 (First) gear, 4LO LOCK for
such obstacles.
3. If wheel spin is experienced, maintain steady throttle,
with your foot off the brake pedal, to allow the
Traction Control System (TCS) to control the wheel
spin. TCS might not operate if the brakes are
applied.
4. If wheel spin cannot be controlled by the TCS, fully
press the brake pedal with your left foot so all
wheel spin is stopped.
5. Back away from the obstacle so that a new
approach can be tried.
6. As the rst wheel crosses the obstacle, be prepared
to alternate the brake and accelerator pedal to
maintain control and avoid tire drop-off from
obstacles. Repeat this process for the other wheels.
For mounds, washouts, loose up-hill
slopes, ditches, etc.
When wheel spin occurs as the vehicle is moving, the
driver may notice a slight shaking or shuddering of
the vehicle. This should be stopped as soon as possible
to prevent damage to vehicle components. This is the
indication that a loss of traction is occurring on this
terrain. The operator should:
1. Reduce speed and apply the brakes.
2. Assess the terrain properly and adjust vehicle
speed and gear ranges accordingly: 4HI position
for higher speeds and 4LO LOCK for more torque
and lower speeds. Transmission 1 (First) gear
is generally recommended.
3. Apply slight pressure to the brake when the shaking
or shuddering sensation is felt, keeping the vehicle
moving in a controlled manner.
4. Be prepared to alternate between braking and
accelerating through the adverse terrain.
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Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut, or bump can startle
you if you are not prepared for them. Often these
obstacles are hidden by grass, bushes, snow, or even
the rise and fall of the terrain itself.
Some things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill?
Will you have to stop suddenly or change direction
quickly?
When driving over obstacles or rough terrain, keep a rm
grip on the steering wheel. Ruts, troughs, or other surface
features can jerk the wheel out of your hands.
When driving over bumps, rocks, or other obstacles, the
wheels can leave the ground. If this happens, even with
one or two wheels, you cannot control the vehicle as well
or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns, or sudden braking.
Off-roading requires a different kind of alertness from
driving on paved roads and highways. There are no road
signs, posted speed limits, or signal lights. Use good
judgment about what is safe and what is not.
Crossing Obstacles
Approach Angle — a Key to Mobility
If you encounter a large dip in the terrain, do not
enter straight on; enter at an angle — 15° minimum
approach (A), 75° maximum approach angle (B). For
very large dips, ditches or small washes, coast in, using
the engine as a brake (transmission and transfer case
lowest gears). Then, use the low ranges in the
transmission and transfer case to power out.
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Driving Downhill
When off-roading takes you downhill, consider:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a hidden
creek bank or even a river bottom with large rocks?
If you decide you can go down a hill safely, try to keep
the vehicle headed straight down. Use a low gear
so engine drag can help the brakes so they do not have
to do all the work. Descend slowly, keeping the
vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can cause
your brakes to overheat and fade. This could cause
loss of control and a serious accident. Apply the
brakes lightly when descending a hill and use a low
gear to keep vehicle speed under control.Things not to do when driving down a hill:
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down might be too steep to drive
across. The vehicle could roll over.
Never go downhill with the transmission in
N (Neutral), called free-wheeling. The brakes will
have to do all the work and could overheat
and fade.
Vehicles are much more likely to stall when going uphill,
but if it happens when going downhill:
1. Stop the vehicle by applying the regular brakes and
apply the parking brake.
2. Shift to P (Park). While still braking, restart the
engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
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