2006 GMC ENVOY XL transmission

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which monitors
operation of the fuel,
ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The check engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after awhile, your emission controls
may not work as well, your fuel economy may not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
3-42

STABILITRAK ACTIVE
The STABILITRAK ACTIVE message will be displayed
anytime the system activates to maintain vehicle
stability. Any combination of engine speed management,
brake traction control, and stability control will display
the STABILITRAK ACTIVE message on the DIC.
STABILITRAK NOT READY
The STABILITRAK NOT READY message may be
displayed if driving conditions delay system initialization.
This is normal. Once the system initializes, the
STABILITRAK NOT READY message will no longer be
displayed on the DIC.
STABILITRAK OFF
The STABILITRAK OFF message will be displayed
when you press the StabiliTrak®button for more than
ve seconds or when stability control has been
automatically disabled. The StabiliTrak
®button is
located on the transmission shift handle.To limit wheel spin and realize the full benets of the
stability enhancement system, you should normally
leave StabiliTrak
®on. However, you should turn
StabiliTrak®off if your vehicle gets stuck in sand, mud,
ice, or snow and you want to rock your vehicle to
attempt to free it, or if you are driving in extreme off-road
conditions and require more wheel spin. SeeIf Your
Vehicle is Stuck in Sand, Mud, Ice, or Snow on
page 4-44. To turn the StabiliTrak
®system back on,
press the StabiliTrak®button again.
There are several conditions that can cause this
message to appear.
The message may be displayed if the brake system
warning light is on. SeeBrake System Warning
Light on page 3-39.
The message will be displayed if the vehicle is
shifted into 4LO.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
3-58

TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear on the DIC and a chime will
sound. Fully reinstall the fuel cap. SeeFilling the Tank
on page 5-8. The diagnostic system can determine
if the fuel cap has been left off or improperly installed. A
loose or missing fuel cap will allow fuel to evaporate
into the atmosphere. The DIC message will remain on
until the message is cancelled with the return button
on the steering wheel. The DIC message will also
be cancelled if the ignition is turned off.
The DIC message and the Service Engine Soon light
may come on again during a second trip if the fuel cap is
still not tightened properly. SeeMalfunction Indicator
Lamp on page 3-42for more information.
TRACTION CONTROL OFF
The TRACTION CONTROL OFF message will be
displayed when you momentarily press the StabiliTrak®
button located on the transmission shift handle. In
this mode, stability control and the brake-traction control
are functional. Engine speed management will be
modied and the driven wheels can spin more freely.
For more details on this mode, seeStabiliTrak
®System
on page 4-9.
TURN SIGNAL ON
If a turn signal is left on for 3/4 of a mile (1.2 km), this
message will appear on the display and you will hear a
chime. Move the turn signal/multifunction lever to the
off position. Press the select button to acknowledge this
message and clear it from the DIC display.
3-59

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.
4-10

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 3-11.
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 5-3for more information.
4-13

Ease up on your speed as you approach the top of
the hill.
Attach a ag to the vehicle to make you more
visible to approaching traffic on trails or hills.
Sound the horn as you approach the top of the hill
to let opposing traffic know you are there.
Use your headlamps even during the day. They
make you more visible to oncoming traffic.
{CAUTION:
Driving to the top (crest) of a hill at full speed
can cause an accident. There could be a
drop-off, embankment, cliff, or even another
vehicle. You could be seriously injured or
killed. As you near the top of a hill, slow down
and stay alert.
Q:What should I do if my vehicle stalls, or is about
to stall, and I cannot make it up the hill?
A:If this happens, there are some things you should
do, and there are some things you must not do.
First, here is what youshoulddo:
Push the brake pedal to stop the vehicle and
keep it from rolling backwards. Also, apply the
parking brake.
If the engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
If the engine has stopped running, you will need to
restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission to
PARK (P) and restart the engine. Then, shift to
REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible in
REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you will be able to tell if the wheels are
straight and maneuver as you back down. It is
best that you back down the hill with the wheels
straight rather than in the left or right direction.
Turning the wheel too far to the left or right
will increase the possibility of a rollover.
4-25

Here are some things youmust notdo if you stall, or
are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) to rev-up the engine and regain
forward momentum. This will not work. Your vehicle
will roll backwards very quickly and you could go
out of control.
Instead, apply the regular brake to stop the vehicle.
Then apply the parking brake. Shift to
REVERSE (R), release the parking brake, and
slowly back straight down.
Never attempt to turn around if you are about to
stall when going up a hill. If the hill is steep
enough to stall your vehicle, it is steep enough to
cause you to roll over if you turn around. If you
cannot make it up the hill, you must back straight
down the hill.
Q:Suppose, after stalling, I try to back down the hill
and decide I just cannot do it. What should I do?
A:Set the parking brake, put the transmission in
PARK (P) and turn off the engine. Leave the vehicle
and go get some help. Exit on the uphill side and
stay clear of the path the vehicle would take if
it rolled downhill. Do not shift the transfer case to
NEUTRAL when you leave the vehicle. Leave
it in some gear.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). This is because
the NEUTRAL position on the transfer case
overrides the transmission. You or someone
else could be injured. If you are going to leave
your vehicle, set the parking brake and shift
the transmission to PARK (P). But do not shift
the transfer case to NEUTRAL. Leave the
transfer case in the Two-Wheel High,
Four-Wheel High or Four-Wheel Low position.
4-26

Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
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, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help the brakes and
they will not have to do all the work. Descend slowly,
keeping your 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.
Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down may be too steep to drive
across. You could roll over if you do not drive
straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.” The
brakes will have to do all the work and could
overheat and fade.
Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going uphill. But if
it happens going downhill, here is what to do.
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) 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.
4-27