service GMC ENVOY 2001 User Guide

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Electronic Transfer Case (If Equipped)
If your four-wheel-drive
vehicle has the electronic
transfer case, the transfer
case switches are to the
right of the steering wheel
on the instrument panel.
Use these switches to shift into and out of four
-wheel
drive. You can choose among three driving settings:
2HI: This setting is for driving in most street and
highway situations. Your front axle is not engaged in
two
-wheel drive. When this lamp is lit, it is about
one
-half as bright as the others.
4HI: This setting engages your front axle to help
drive your vehicle. Use 4HI when you need extra
traction, such as on snowy or icy roads, or in most
off
-road situations.4LO: This setting also engages your front axle to give
you extra traction. You may never need 4LO. It sends
the maximum power to all four wheels. You might
choose 4LO if you were driving off
-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the switches show you which setting
you are in. The indicator lights will come on briefly
when you turn on the ignition and one will stay on.
If the lights do not come on, you should take your
vehicle in for service. An indicator light will flash while
shifting. It will remain illuminated when the shift
is completed.
Shifting from 2HI to 4HI
Press and release the 4HI switch. This can be done at
any speed, and the front axle will lock automatically.
Shifting from 4HI to 2HI
Press and release the 2HI switch. This can be done at
any speed, and the front axle will unlock automatically.
Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) in vehicles equipped
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with an automatic transmission or the clutch pedal
engaged in vehicles equipped with a manual
transmission. The preferred method for shifting into
4LO is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4LO switch.
You must wait for the 4LO indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear or releasing the clutch pedal.
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light will flash
for 30 seconds and not complete the shift unless your
vehicle is moving slower than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N) or the clutch
pedal engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4LO, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4LO switch. While the 4LO indicator light is flashing,
shift your transmission into PARK (P). Wait until the
4LO indicator light remains illuminated before shifting
your transmission into gear. This will get you into 4LO,
but you should take your vehicle in for service to restore
normal operation.Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must
be stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) or the clutch pedal
engaged. The preferred method for shifting out of
4LO is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4HI switch.
You must wait for the 4HI indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear or releasing the clutch pedal.
If the 4HI switch is pressed when your vehicle is in
gear and/or moving, the 4HI indicator light will flash
for 30 seconds but not complete the shift unless the
vehicle is moving slower than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N) or the clutch
pedal engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4HI, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4HI switch. While the 4HI indicator light is flashing,
shift your transmission into PARK (P). Wait until the
4HI indicator light remains illuminated before shifting
your transmission into gear. This will get you into 4HI,
but you should take your vehicle in for service to restore
normal operation.
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4HI: Use 4HI when you need extra traction, such as
on snowy or icy roads or in most off
-road situations.
This setting also engages your front axle to help drive
your vehicle.
4LO: This setting also engages your front axle and
delivers extra torque. You may never need 4LO. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off
-road in deep sand, deep mud,
deep snow and climbing or descending steep hills.
CAUTION:
Shifting the transfer case to NEUTRAL can cause
your vehicle to roll even if the transmission is in
PARK (P), or if you have a manual transmission,
even if you are in gear. You or someone else could
be seriously injured. Be sure to set the parking
brake before placing the transfer case in
NEUTRAL. See ªParking Brakeº in the Index.
NEUTRAL: Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
ªRecreational Vehicle Towingº or ªTowing Your
Vehicleº in the Index for more information.
Indicator lights in the switches show which setting you
are in. The indicator lights will come on briefly when
you turn on the ignition and one will stay on. If the
lights do not come on, you should take your vehicle
to your dealer for service. An indicator light will
flash while shifting the transfer case. It will remain
illuminated when the shift is complete. If for some
reason the transfer case cannot make a requested shift,
it will return to the last chosen setting.
If the SERVICE 4WD light stays on, you should take
your vehicle to your dealer for service. See ªService
4WDº in the Index for further information.
Shifting to 4HI or AUTO 4WD
Press and release the 4HI or AUTO 4WD switch.
This can be done at any speed, and the indicator light
will flash while shifting. It will remain illuminated when
the shift is complete.
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Accessory Inflator (If Equipped)
Your vehicle may be equipped with an air inflator
system. With it, you can inflate things like air mattresses
and basketballs, and you can also use it to bring your
tires up to the proper pressure.
The air inflator is located
in the rear compartment on
the passenger's side of the
vehicle. To remove the
cover, pull the tab on the
cover and pull it off.
The air inflator kit includes an 18
-foot (5.5 m) hose with
three nozzle adapters.
CAUTION:
Inflating something too much can make it explode,
and you or others could be injured. Be sure to read
the inflator instructions, and inflate any object
only to its recommended pressure.
To use your air inflator
attach the appropriate
nozzle adapter, if required,
to the end of the hose.
Then attach that end of
the hose to the object you
wish to inflate. Remove the
protective cap covering the
outlet. Attach the other end
of the hose to the outlet.
Press the ON switch.
If the air inflator system does not turn on, the fuse may
be blown or installed incorrectly. See ªFuses and Circuit
Breakersº in the Index or see your dealer for service.
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OnStar
System (If Equipped)
OnStar is a vehicle communications system that
offers a variety of services and provides a hands
-free
communication link between you and the OnStar Center.
A service subscription agreement and fee are required in
order to receive OnStar service. Services are available
24 hours a day, 7 days a week. For more information,
call 1
-888-ONSTAR-7 (1-888-667-8277).
OnStar Services Button: Press this button once
to contact an advisor who will be able to assist you with
these services. If you are not quickly connected, the
system will automatically reset and redial. This ensures
connection to the center; there is no additional action
required. Press the Call Answer/End button to cancel the
automatic redial.
Emergency Button: In an emergency situation,
press the emergency service button. Upon receiving the
call, an advisor at the center will locate your vehicle and
assess the situation. If necessary, the advisor will alert
the nearest emergency service provider.
Call ANSWER/END Button: Use this button
to answer a call. (If you are receiving a call, the audio
system will mute, and the ring will be heard). Press this
button at the end of a call to disconnect and return the
audio system to its previous settings. This button will
also cancel a call if one of the buttons is accidentally
pressed or if the automatic redial function is activated.
Volume Control: You can control the volume of the
OnStar System using either the volume control knob
on the radio or using the steering wheel volume control
(if equipped).
Telltale Light: This light will indicate the status of the
system. A solid green light will come on when you start
the vehicle to let you know that the system is on and is
ready to make or receive calls.
If the light blinks green it means that an incoming
or outgoing call is in progress. Press the Call
ANSWER/END button if you notice the light
blinking and you are not on a call.
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The light will be red in the event of an OnStar system
malfunction. If this occurs press the OnStar button to
attempt to contact an advisor. If the connection is made,
the advisor will assist you with steps to take to make
sure that the system is functioning properly. If you
cannot contact the advisor, take your vehicle to your
dealership as soon as possible for assistance.
Safety and Security Services

Automatic Notification of Air Bag
Deployment
-- If an air bag deploys, a priority
emergency signal is automatically sent to the center.
An advisor will locate your vehicle's position, try to
contact you and assist you in the situation. If the
center is unable to contact you, an emergency service
provider will be contacted.

Stolen Vehicle Tracking
-- Call the center at
1
-888-4-ONSTAR (1-888-466-7827) to report your
vehicle stolen. The system can then locate and track
your vehicle and the advisor will be able to notify
the proper authorities.

Roadside Assistance with Location
-- For vehicle
breakdowns, press the OnStar button. An advisor
will contact the appropriate help.
Remote Diagnostics
-- If an instrument panel light
comes on, the center can perform a check of the
engine on
-board computer. An advisor can then
recommend what action needs to be taken.

OnStar MED
-NET -- Med-Net can store your
personal medical history and provide it to emergency
personnel if necessary.

Accident Assist
-- An advisor can provide
step
-by-step guidance following an accident.

Remote Door Unlock
-- To contact the center,
call 1
-888-4-ONSTAR. You will be required to
provide your security information. An advisor will
send a command to your vehicle to unlock itself.
The advisor can delay unlocking your vehicle.
Remote Door Unlock is disabled 48 hours after
the vehicle is parked to maintain the battery charge.

Vehicle Locator Service
-- To contact the center,
call 1
-888-4-ONSTAR. You will be required to
provide your security information. An advisor will
send a command to your vehicle to sound the horn
and/or flash the lamps.
In order to provide you with excellent service, calls with
the OnStar Center may be monitored or recorded.
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Premium Services (Includes Safety and
Security Services)

Route Support -- An advisor can provide directions
or guidance to anywhere you want to go. In addition,
they can help you locate gas stations, rest areas,
ATMs, hospitals, hotels, stores, eateries and more.

Concierge Services
-- The concierge advisor can
obtain tickets, reservations, or help with vacation/trip
planning and other unique items and services.

Ride Assist
-- An advisor can locate transportation
in the event that you are unable to drive.
OnStar System Limitations
Complete limitations can be found on the Subscriber
Services Agreement.
OnStar Service is:

available in the 48 contiguous United States, Alaska,
Hawaii and Canada;

available when the vehicle is within the operating
range of a cellular provider;
subject to limitations caused by atmospheric
conditions, such as severe weather or topographical
conditions, such as mountainous terrain;

subject to cellular carrier equipment limitations.
Global positioning capabilities used to deliver
OnStar Service will not be available if satellite
signals are obstructed.
OnStar will not function if the vehicle's battery is
discharged or disconnected. It may also be inoperative
if the vehicle is in an accident and the OnStar or vehicle
electrical system components are damaged.
Safety and security services are provided by existing
governmental emergency service providers. OnStar
will use reasonable efforts to contact the appropriate
emergency service provider and request assistance but
cannot promise that they will respond to the call in a
timely manner or at all.
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Full-Size Console
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference,
and (2) this device must accept any interference received,
including interference that may cause undesired operation.
This device complies with RSS
-210 of Industry Canada.
Operation is subject to the following two conditions:
(1) this device may not cause interference, and (2) this
device must accept any interference, including interference
that may cause undesired operation of the device.
Changes and modifications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Programming the Transmitter
Do not use the HomeLink Transmitter with any garage
door opener that does not have the ªstop and reverseº
feature. This includes any garage door opener model
manufactured before April 1, 1982.
Be sure that people and objects are clear of the garage
door you are programming.
Your vehicle's engine should be turned off while
programming the transmitter. Follow these steps to
program up to three channels:
1. If you have previously programmed a transmitter
channel, proceed to Step 2. Otherwise, hold
down the two outside buttons on the HomeLink
Transmitter until the indicator light begins to flash
rapidly (after 20 seconds). Then release the buttons.
This procedure initializes the memory and erases any
previous settings for all three channels.
2. Decide which one of the three channels you want to
program. Hold the end of the hand
-held transmitter
about 1 to 3 inches (3 to 8 cm) away from the
surface of the HomeLink Transmitter so that you
can still see the indicator light.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag's electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the air bag sensors, the
air bag modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, see ªAir Bagº in the Index.
This light will come on
when you start your vehicle,
and it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN.
If the light doesn't come on then, have it fixed so
it will be ready to warn you if there is a problem.
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You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Shift Light
You have the shift light
on the instrument panel
cluster if you have a
manual transmission.
Shifting when the indicator light is on will help you get
the best fuel economy. See ªShift Lightº in the Index.
Brake System Warning Light
When the ignition is on, the brake system warning light
will come on when you set your parking brake. The light
will stay on if your parking brake doesn't release fully.
If it stays on after your parking brake is fully released,
it means you have a brake problem.
Your vehicle's hydraulic brake system is divided into
two parts. If one part isn't working, the other part can
still work and stop you. For good braking, though, you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
United States Canada
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