2007 GMC ENVOY light

Control of a Vehicle
You have three systems that make your
vehicle go where you want it to go. They are
the brakes, the steering, and the accelerator.
All three systems have to do their work at
the places where the tires meet the road.
Sometimes, as when you are driving on snow or
ice, it is easy to ask more of those control systems
than the tires and road can provide. That means
you can lose control of your vehicle.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 380.
Braking
SeeBrake System Warning Light on page 206.
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake
pedal. That is perception time. Then you have to
bring up your foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds
or more with another. Age, physical condition,
alertness, coordination, and eyesight all play a part.
So do alcohol, drugs, and frustration. But even in
three-fourths of a second, a vehicle moving at
60 mph (100 km/h) travels 66 feet (20 m). That
could be a lot of distance in an emergency, so
keeping enough space between your vehicle and
others is important.
And, of course, actual stopping distances vary
greatly with the surface of the road, whether it is
pavement or gravel; the condition of the road,
whether it is wet, dry, or icy; tire tread; the
condition of the brakes; the weight of the vehicle;
and the amount of brake force applied.
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Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic.
This is a mistake. The brakes may not have time to
cool between hard stops. The brakes will wear out
much faster if you do a lot of heavy braking. If you
keep pace with the traffic and allow realistic
following distances, you will eliminate a lot of
unnecessary braking. That means better braking
and longer brake life.
If your vehicle’s engine ever stops while you are
driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder to
push down. If the engine stops, you will still have
some power brake assist. But you will use it
when you brake. Once the power assist is used
up, it may take longer to stop and the brake pedal
will be harder to push.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 380.Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock Brake System
(ABS), an advanced electronic braking system that
will help prevent a braking skid.
When you start your engine and begin to drive
away, ABS will check itself. You may hear a
momentary motor or clicking noise while this test
is going on. This is normal.
If there is a problem
with ABS, this warning
light will stay on.
SeeAnti-Lock Brake
System Warning
Light on page 207.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP
problem, both the brake and ABS warning lights will
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 for service.
307

For more information on the stability messages,
seeDIC Warnings and Messages on page 222.
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.
You may also feel or hear the system 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.
310

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.
StabiliTrak®Off
In this mode, both stability control and part of the
traction control system are disabled. Your vehicle
will still have brake-traction control, but will not be
able to use the engine speed management system.
You may still hear system noises 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 your vehicle is stuck in
sand, mud, ice or snow, and you may want
to “rock” your 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 348for
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.
311

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).
Solid Traction Control Off Solid OffTraction Control
Off Mode
Solid StabiliTrak
®Off Solid OffStabiliTrak
®Off Mode
(StabiliTrak®indicator light
will ash when system rst
enters this mode).
Blinking StabiliTrak
®Active Blinking OffStabiliTrak
®system activates
using engine speed
management, brake traction
control, and/or stability
control.
Solid Service StabiliTrak
®Solid SolidStabiliTrak
®system is
disabled due to a
system fault.
SolidStabiliTrak
®
Not ReadySolid OffStabiliTrak
®system is
disabled due to a failure
to initialize.
312

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. If you do, you may be causing
damage to the transfer case. This could lead to
costly repairs not covered by your warranty.
Notice:If you allow the wheel(s) of one axle
to spin excessively while the StabiliTrak
®,
ABS and brake warning lights and the
SERVICE STABILITRAK message are
displayed, you could damage the transfer
case. The repairs would not be covered by your
warranty. Reduce engine power and do not
spin the wheel(s) excessively while these lights
and this message 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, you may
notice a reduction in acceleration, or may hear a
noise or vibration. This is normal.If your vehicle is in cruise control when the system
activates, the StabiliTrak
®light will blink, and
the cruise control will automatically disengage.
When road conditions allow, you may re-engage
the cruise control. SeeCruise Control on
page 176.
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, you should see your dealer for service.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 380for more information.
313

Off-Road Recovery
You may nd that your right wheels have dropped
off the edge of a road onto the shoulder while
you are 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 your vehicle straddles the edge
of the pavement. You can turn the steering wheel
up to one-quarter turn until the right front tire
contacts the pavement edge. Then turn your
steering wheel to go straight down the roadway.
Passing
The driver of a vehicle about to pass another on a
two-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead, then
goes back into the right lane again. A simple
maneuver?
Not necessarily! Passing another vehicle on a
two-lane highway is a potentially dangerous move,
since the passing vehicle occupies the same
lane as oncoming traffic for several seconds.
A miscalculation, an error in judgment, or a brief
surrender to frustration or anger can suddenly
put the passing driver face to face with the worst
of all traffic accidents — the head-on collision.
So here are some tips for passing:
Drive ahead. Look down the road, to the sides,
and to crossroads for situations that might
affect your passing patterns. If you have any
doubt whatsoever about making a successful
pass, wait for a better time.
316

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. Here are 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?
There is more discussion of these subjects
later.
Will you have to stop suddenly or change
direction quickly?
When you drive 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 if you are not
prepared.When you drive 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.
In a way, off-road driving requires a different kind
of alertness from driving on paved roads and
highways. There are no road signs, posted speed
limits, or signal lights. You have to use your
own good judgment about what is safe and
what is not.
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.
SeeDrunken Driving on page 303.
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