2001 GMC SIERRA service

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The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps after
you restart the vehicle, you will need to press the fog
lamp switch again.
Auxiliary Roof Mounted Lamp Switch
(If Equipped)
If your vehicle has this
feature, this switch includes
wiring provisions for a
dealer or a qualified service
center to install an auxiliary
roof lamp. This switch is
located on the center of the
instrument panel near the
comfort controls.
When the switch wiring is connected to an auxiliary roof
mounted lamp, pressing the switch will activate the lamp
and illuminate an indicator light near the button. Pressing
the switch again will turn off the roof mounted lamp.
If your vehicle has this switch, your vehicle may have
the snow plow prep package. For further information see
ªSnow Plow Prep Packageº in the Index.
Interior Lamps
Instrument Panel Intensity Control
The instrument panel intensity control is located to the
right of the headlamp switch.
Turn the thumbwheel up to adjust the instrument panel
lights. To turn on the dome lamps (with the vehicle
doors closed) turn the thumbwheel all the way up.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition. The lights will not
come on if the DOME OVERRIDE button is pressed in.
Illuminated Entry
Your vehicle is equipped with an illuminated entry feature.
When a door is opened, the dome lamps will come on if
the DOME OVERRIDE button is in the ªoutº position.
If the DOME OVERRIDE button is pressed in, the
lamps will not come on.

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Accessory Power Outlets
Two accessory power outlets are located near the
cigarette lighter. Use these outlets to power mobile
telephones or other devices designed to operate with
vehicle electrical systems.
The cigarette lighter is designed to fit only in the
receptacle to the right of the accessory power outlets.
Certain accessory power plugs may not be compatible
to the accessory power outlets and could result in blown
vehicle or adapter fuses. If you experience a problem,
see your dealer for additional information on the
accessory power outlets.
Sun Visors
To block out glare, you can swing down the visors.
You can also swing them out to help block glare at the
front and side windows.
The passenger's side sun visor may have a vanity mirror.
Cellular Telephone (If Equipped)
Your vehicle may be prewired for a cellular telephone.
Please consult your GM dealer or a qualified service
center for further information.
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).

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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 controls, 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.
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.

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Safety and Security Services

Automatic Notification of Air Bag
Deployment
-- If an air bag deploys, a priority
emergency signal is sent automatically 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 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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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, the passenger air bag suppression
circuit 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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CAUTION:
If the air bag readiness light ever comes on when
you have turned off the air bag, it means that
something may be wrong with the air bag system.
The right front passenger's air bag could inflate
even though the switch is off.
If your vehicle is a regular cab pickup and this
ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in your
vehicle) until you have your vehicle serviced.
If your vehicle is an extended cab pickup and this
ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in the right
front passenger's seat) until you have your
vehicle serviced.
Voltmeter
United States Canada
When your engine is not running, but the ignition is in
RUN, this gage shows your battery's state of charge
in DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.

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Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
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 (If Equipped)
This light is used on
some models with
manual transmissions.
The SHIFT indicator light will help you get the best fuel
economy. See ªShift Lightº or ªShift Speedsº in the
index for more information.
Brake System Warning Light
With the ignition on, the brake system warning light will
flash when you set the parking brake. The light will flash
if the parking brake doesn't release fully. If you try to
drive with the parking brake engaged, a chime will sound
when the vehicle speed is greater than 3 mph (5 km/h).
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