light GMC ENVOY 2009 Manual Online

Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
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.
This is normal.
If there is a problem with
ABS, this warning light
stays on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-36.
Along with ABS, the vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights come on
accompanied by a 10-second chime. The lights and
chime will come on each time the ignition is turned on
until the problem is repaired. See your dealer/retailer
for service.Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
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 front wheel
and at both rear wheels.
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.
4-5

When the StabiliTrak
system is both on and
actively controlling the
stability of the vehicle, the
StabiliTrak light will blink for
the duration of the event.
The system may be heard or felt while it is working.
This is normal.
The StabiliTrak disable
button is located on the
transmission shift handle.
The StabiliTrak system is automatically disabled in
4LO mode and cannot be turned on until the vehicle is
switched to 2HI, 4HI, or 4AWD.
The StabiliTrak system has three modes of operation:
STABILITRAK ON, TRACTION CONTROL OFF, and
STABILITRAK OFF.
STABILITRAK ON — The vehicle will default to
STABILITRAK ON every time the driver starts the
vehicle. The StabiliTrak light will be off and no DIC
messages will be displayed.TRACTION CONTROL OFF — The driver can modify
the engine speed management system by momentarily
pressing the StabiliTrak button on the transmission shift
handle. The StabiliTrak light will come on and TRACTION
CONTROL OFF will be displayed. For vehicles without
a DIC, the StabiliTrak indicator light will come on.
Momentarily pressing the StabiliTrak button again will
return the system to the STABILITRAK ON mode.
STABILITRAK OFF — The driver can turn off
StabiliTrak by pressing the StabiliTrak button for more
than ve seconds. The StabiliTrak light will come on
and STABILITRAK OFF will be displayed. For vehicles
without a DIC, the StabiliTrak indicator light will
come on. Momentarily pressing the StabiliTrak button
again will return the system to the STABILITRAK
ON mode. See StabiliTrak Off below for more
information.
Traction Control Off
In this mode, stability control and brake-traction control
are functional. Engine speed management will be
modied and the driven wheels can spin more freely.
This can cause the brake-traction control to activate
more frequently. If the controller detects excessive wheel
spin in this mode, the StabiliTrak indicator light may
blink and the STABILITRAK ACTIVE message may be
displayed to warn the driver that damage may occur
to the transfer case.
4-7

StabiliTrak Off
In this mode, both stability control and part of the traction
control system are disabled. The vehicle will still have
brake-traction control, but will not be able to use the
engine speed management system. System noises may
be heard as a result of the brake-traction control coming
on. If the controller detects excessive wheel spin in this
mode, the StabiliTrak indicator light may blink and the
STABILITRAK ACTIVE message may be displayed
to warn the driver that damage may occur to the
transfer case.
It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn
the system off if the vehicle is stuck in sand, mud, ice orsnow, and you may want to “rock” the vehicle in an
attempt to free it. It may also be necessary to turn off the
system when driving in extreme off-road conditions
where high wheel spin is required. SeeIf Your Vehicle
is Stuck in Sand, Mud, Ice, or Snow on page 4-30
for more information.
When the transfer case is in 4LO, the stability system is
automatically disabled. The StabiliTrak light will come
on and the STABILITRAK OFF message will appear on
the DIC. The StabiliTrak system cannot be turned on
until the vehicle is switched to 2HI, 4HI, or 4AWD.
The following chart describes the StabiliTrak system
events and the corresponding messages and lights that
will be displayed on the instrument panel cluster.
Vehicles with a DIC Vehicles without a DIC Event
StabiliTrak
Indicator LightDIC MessageStabiliTrak
Indicator LightStabiliTrak
Service Light—
Off None Off OffStabiliTrak On mode (System is fully
enabled, but is not actively
controlling vehicle stability).
SolidTraction
Control OffSolid Off Traction Control Off Mode
Solid StabiliTrak Off Solid OffStabiliTrak Off Mode (StabiliTrak
indicator light will ash when system
rst enters this mode).
4-8

Vehicles with a DIC Vehicles without a DIC Event
Blinking StabiliTrak Active Blinking OffStabiliTrak system activates using
engine speed management, brake
traction control, and/or stability
control.
SolidService
StabiliTrakSolid SolidStabiliTrak system is disabled due to
a system fault.
SolidStabiliTrak Not
ReadySolid OffStabiliTrak system is disabled due to
a failure to initialize.
Notice:If the StabiliTrak
®light comes on due to
heavy braking and/or because the traction control
system has been continuously active, do not allow
the wheel(s) of one axle to spin excessively. This
could lead to damage to the transfer case and costly
repairs not covered by the vehicle warranty.
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 be damaged. 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.StabiliTrak 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 the system activates,
the StabiliTrak light will ash and cruise control will
automatically disengage. Cruise control may be
reengaged when road conditions allow. SeeCruise
Control on page 3-10.
4-9

StabiliTrak will turn off automatically if a problem is
detected in the system. The StabiliTrak light will come
on and SERVICE STABILITRAK will be displayed on
the DIC. For vehicles without a DIC, the StabiliTrak light
and the StabiliTrak service light will both come on. If the
SERVICE STABILITRAK message (or StabiliTrak service
light) does not clear itself after restarting the vehicle, see
your dealer/retailer for service.
Adding non-GM accessories can affect the vehicle’s
performance. SeeAccessories and Modifications
on page 5-3for more information.
Locking Rear Axle
Vehicles with a locking rear axle can give more traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when traction is low,
this feature will allow the rear wheel with the most
traction to move the vehicle.
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.
4-10

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.
4-12

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.
Driving on Hills
Off-road driving often takes you up, down, or across a
hill. Driving safely on hills requires good judgment
and an understanding of what the vehicle can and
cannot do. There are some hills that simply cannot be
driven, no matter how well built the vehicle.
{CAUTION:
Many hills are simply too steep for any vehicle. If
you drive up them, you will stall. If you drive down
them, you cannot control your speed. If you drive
across them, you will roll over. You could be
seriously injured or killed. If you have any doubt
about the steepness, do not drive the hill.
Approaching a Hill
When you approach a hill, decide if it is too steep to
climb, descend, or cross. Steepness can be hard to
judge. On a very small hill, for example, there may be a
smooth, constant incline with only a small change in
elevation where you can easily see all the way to the top.
On a large hill, the incline may get steeper as you near
the top, but you might not see this because the crest of
the hill is hidden by bushes, grass, or shrubs.
4-17

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) and, 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.
4-21

Driving at Night
Night driving is more dangerous than day driving because
some drivers are likely to be impaired — by alcohol or
drugs, with night vision problems, or by fatigue.
Night driving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by adjusting the inside
rearview mirror.
Slow down and keep more space between you and
other vehicles because headlamps can only light up
so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into approaching headlamps.
Keep the windshield and all glass on your vehicle
clean — inside and out.
Keep your eyes moving, especially during turns or
curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
Driving in Rain and on Wet Roads
Rain and wet roads can reduce vehicle traction
and affect your ability to stop and accelerate. Always
drive slower in these types of driving conditions
and avoid driving through large puddles and
deep-standing or owing water.
{CAUTION:
Wet brakes can cause crashes. They might not
work as well in a quick stop and could cause pulling
to one side. You could lose control of the vehicle.
After driving through a large puddle of water or a
car/vehicle wash, lightly apply the brake pedal until
the brakes work normally.
Flowing or rushing water creates strong forces.
Driving through owing water could cause your
vehicle to be carried away. If this happens, you and
other vehicle occupants could drown. Do not ignore
police warnings and be very cautious about trying to
drive through owing water.
4-25

CAUTION: (Continued)

Open a window about two inches (5 cm) on
the side of the vehicle that is away from the
wind to bring in fresh air.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting. See
Climate Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-37.
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill you.
You cannot see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking the exhaust.Run the engine for short periods only as needed to
keep warm, but be careful.
To save fuel, run the engine for only short periods as
needed to warm the vehicle and then shut the engine
off and close the window most of the way to save heat.
Repeat this until help arrives but only when you feel
really uncomfortable from the cold. Moving about
to keep warm also helps.
If it takes some time for help to arrive, now and then when
you run the engine, push the accelerator pedal slightly so
the engine runs faster than the idle speed. This keeps the
battery charged to restart the vehicle and to signal for
help with the headlamps. Do this as little as possible to
save fuel.
4-29