2007 GMC ENVOY DENALI Owners Manual

But the ability to drive is affected well below a BAC
of 0.10 percent. Research shows that the driving
skills of many people are impaired at a BAC
approaching 0.05 percent, and that the effects are
worse at night. All drivers are impaired at BAC
levels above 0.05 percent. Statistics show that the
chance of being in a collision increases sharply for
drivers who have a BAC of 0.05 percent or above.
A driver with a BAC level of 0.06 percent has
doubled his or her chance of having a collision. At a
BAC level of 0.10 percent, the chance of this driver
having a collision is 12 times greater; at a level of
0.15 percent, the chance is 25 times greater!
The body takes about an hour to rid itself of the
alcohol in one drink. No amount of coffee or
number of cold showers will speed that up.
“I will be careful” is not the right answer. What if
there is an emergency, a need to take sudden
action, as when a child darts into the street?
A person with even a moderate BAC might not
be able to react quickly enough to avoid the
collision.There is something else about drinking and driving
that many people do not know. Medical research
shows that alcohol in a person’s system can make
crash injuries worse, especially injuries to the
brain, spinal cord, or heart. This means that when
anyone who has been drinking — driver or
passenger — is in a crash, that person’s chance
of being killed or permanently disabled is
higher than if the person had not been drinking.
{CAUTION:
Drinking and then driving is very
dangerous. Your reexes, perceptions,
attentiveness, and judgment can be
affected by even a small amount of
alcohol. You can have a serious — or
even fatal — collision if you drive after
drinking. Please do not drink and drive
or ride with a driver who has been
drinking. Ride home in a cab; or if you
are with a group, designate a driver
who will not drink.
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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.
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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 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 faster than
any driver could. The computer is programmed
to make the most of available tire and road
conditions. This can help you steer around the
obstacle while braking hard.
As you brake, your computer keeps receiving
updates on wheel speed and controls braking
pressure accordingly.
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Remember: ABS does not change the time you
need to get your foot up to the brake pedal or
always decrease stopping distance. If you get too
close to the vehicle in front of you, you will not have
time to apply your brakes if that vehicle suddenly
slows or stops. Always leave enough room up
ahead to stop, even though you have ABS.
Using ABS
Do not pump the brakes. Just hold the brake
pedal down rmly and let anti-lock work for you.
You may feel the brakes vibrate, or you may notice
some noise, but this is normal.
Braking in Emergencies
With ABS, you can steer and brake at the same
time. In many emergencies, steering can help you
more than even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear
axle can give you additional traction on snow, mud,
ice, sand or gravel. It works like a standard axle
most of the time, but when one of the rear wheels
has no traction and the other does, this feature will
allow the wheel with traction to move the vehicle.
StabiliTrak®System
Your vehicle is equipped with StabiliTrak®,
Electronic Stability Control (ESC) which combines
antilock brake, traction and stability control systems
and helps the driver maintain directional control of
the vehicle in most driving conditions.
Traction control activates when the controller
senses wheel spin. StabiliTrak
®will selectively
apply the brakes and reduce engine torque to help
regain traction.
Stability control activates when the controller
senses a discrepancy between your intended path
and the direction the vehicle is travelling.
StabiliTrak
®selectively applies braking pressure at
any one of the vehicle’s brakes to help guide the
vehicle in the direction which you are steering.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic
checks to insure there are no problems. You may
hear or feel the system working. This is normal and
does not mean there is a problem with your vehicle.
If driving conditions delay system initialization, the
STABILITRAK NOT READY message may be
displayed. If this is the case, your vehicle does not
need servicing.
309

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