2003 GMC SIERRA light

SERVICE AIRBAG
If there is a problem with the air bag system, this
message will be displayed on the DIC. Have a qualified
technician inspect the system for problems. Pressing
the select button will acknowledge this message
and clear it from the DIC display.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the brake
system needs service.
SERVICE BRAKE BOOSTER
If your vehicle has vaccum assist power brakes, this
message will be displayed on the DIC when there is a
problem with the Supplemental Brake Assist system.
If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
SeeBrake System Warning Light on page 3-34.
{CAUTION:
Your brake system may not be working
properly if the SERVICE BRAKE BOOSTER
message is displayed.
If the brake system warning light is also on,
you should have the vehicle towed for service.
See“Brake System Warning Light”in the
Index.
If the brake system warning light isn’t on, you
still have brakes, but the supplemental brake
assist system may not operate properly. In the
event of a vacuum loss, you may not have
vacuum power assist for braking. The brake
pedal will be harder to push and it will take
longer to stop. If you continue to drive with
this message displayed it can lead to a crash.
Have the brake system serviced as soon as
possible.
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CD Changer
The compact disc changer plays up to six standard size
CDs continuously. Individual CDs may be loaded or
ejected into or from any position.
A green light on each numbered button indicates a CD
is loaded in the respective position. An amber light
on a numbered button indicates that a CD is playing.
When loading CDs, the loading slot indicators turn
amber to indicate that the player is ready to accept a
CD. CDs can be loaded or ejected with the radio or the
ignition being on or off.
You must load CDs with the label side up. If you do not,
the player will automatically eject the CDs.
Notice:Loading CDs with adhesive labels will
damage the player.
To load a CD, perform the following steps:
1. Press the LOAD button. Available positions will
blink amber.
2. Select a position by pressing the desired numbered
button with the amber blinking light. If a button is
not pressed withinfive seconds, the changer will go
to the lowest available position.
3. Load the CD when the loading slot indicators turn
amber. An internal door will open allowing a single
CD to be inserted into the changer. After
approximately 10 seconds the changer will be ready
to play.
To load two or more CDs, perform the
following steps:
1. Press and hold the LOAD button. Thefirst CD will
be loaded into the lowest numbered empty position.
2. Load a single CD when the loading slot indicators
turn amber. After about 10 seconds the changer will
cycle to the next available position.
3. Repeat Step 2 until all CDs are loaded into all of
the desired positions. If you do not wish to load all
of the positions, you can cancel the load all
function by pressing a button with a greenflashing
indicator light or wait 20 seconds for the changer
to time out.
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2003 - Sierra Denali

To eject a single CD, perform the following
steps:
1. Press the eject button (upward pointing arrow).
The buttons with loaded CDs will blink amber.
2. Press one of the amber blinking buttons to select
the location of the CD you want to eject. The
changer will move to that location and eject the CD.
If you do not remove the CD from the player
within 10 seconds, it will be reloaded. If the eject
button is pressed and a numbered location button is
not pressed withinfive seconds, the current or
last played CD will be ejected.
To eject all CDs, press and hold the eject button.
There are two ways to play a CD. Perform
one of the following:
•
With the radio on, press the desired numbered
button with a green indicator light on the CD
changer.
•Press the TAPE DISC button on the radio. The CD
changer will go to its last played position.
CD Functions
1 PREV (Previous):Press this pushbutton to go to the
previous track if the current track has been playing
for less than eight seconds. If pressed when the current
track has been playing for more than eight seconds,
it will go to the beginning of the current track. If you hold
or press this pushbutton more than once, the player
will continue moving back through the CD.
2 NEXT:Press this pushbutton to go to the next track.
If you hold this pushbutton or press it more than
once, the player will continue moving forward through
the CD.
3 REV (Reverse):Press and hold this pushbutton to
reverse quickly through a track. Release it to resume
playing.
4 FWD (Forward):Press and hold this pushbutton to
advance quickly through a track. Release it to resume
playing.
5
X:Press this pushbutton to select a CD. The CD
number and track number will be displayed.
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6 RDM (Random):Press this button to hear the tracks
in random, rather than sequential, order. RDM ALL
will appear on the radio display, which will randomly play
all of the loaded CDs. Press and hold this button until
you hear a beep and the radio will display RDM
ONE, which will randomly play the tracks on the current
CD. Press this button again to turn off random play,
RDM OFF will appear on the radio display.
qSEEKr:Press the right or the left SEEK arrow to
go to the next or to the previous track on the CD.
BAND:Press BAND to listen to the radio when a CD is
playing.
TAPE DISC:Press this button if you have a CD loaded
in the changer and the radio is turned on, to play a
CD. Press this button to switch between playing a tape
and the CD changer if all are loaded.
Compact Disc Changer Errors
CHK CD (Check):If this message appears on the
display, it could be for one of the following reasons:
•You are driving on a very rough road. The CD
should play when the road gets smoother.
•A CD is upside down.
•It is dirty, scratched or wet.
•It is very humid. If so, wait about an hour and try
again.
•The CD player is very hot.
If any error occurs repeatedly or if an error cannot be
corrected, contact your dealership.
Theft-Deterrent Feature
THEFTLOCK®is designed to discourage theft of your
radio. The feature works automatically by learning
a portion of the Vehicle Identification Number (VIN).
If the radio is moved to a different vehicle, it will
not operate and LOCKED will be displayed.
When the radio and vehicle are turned off, the blinking
red light indicates that THEFTLOCK
®is armed.
With THEFTLOCK
®activated, your radio will not operate
if stolen.
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XM™Satellite Radio Service (United
States Only)
XM™Satellite Radio gives you digital radio reception
from coast to coast. Just as with FM, tall buildings
or hills can interfere with satellite radio signals, causing
the sound to come and go. Your radio may display
“NO SIGNAL”to indicate interference.
Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren’t, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLN to
indicate that you have used your tape player for
50 hours without resetting the tape clean timer. If this
message appears on the display, your cassette
tape player needs to be cleaned. It will still play tapes,
but you should clean it as soon as possible to
prevent damage to your tapes and player. If you notice
a reduction in sound quality, try a known good
cassette to see if the tape or the tape player is at fault.
If this other cassette has no improvement in sound
quality, clean the tape player.For best results, use a scrubbing action, non-abrasive
cleaning cassette with pads which scrub the tape
head as the hubs of the cleaner cassette turn. The
recommended cleaning cassette is available through
your dealership.
The cut tape detection feature of your cassette tape
player may identify the cleaning cassette as a damaged
tape, in error. To prevent the cleaning cassette from
being ejected, use the following steps:
1. Turn the ignition on.
2. Turn the radio off.
3. Press and hold the TAPE AUX button forfive
seconds. The tape symbol on the display will
flash for two seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer’s
recommended cleaning time.
After the cleaning cassette is ejected, the cut tape
detection feature will be active again.
You may also choose a non-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to
clean the tape head. This type of cleaning cassette will
not eject on its own. A non-scrubbing action cleaner
may not clean as thoroughly as the scrubbing type
cleaner. The use of a non-scrubbing action, dry-type
cleaning cassette is not recommended.
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After you clean the player, press and hold the EJECT
button forfive seconds to reset the CLN indicator.
The radio will display --- or CLEANED to show the
indicator was reset.
Cassettes are subject to wear and the sound quality
may degrade over time. Always make sure the cassette
tape is in good condition before you have your tape
player serviced.
Care of Your CDs
Handle discs carefully. Store them in their original cases
or other protective cases and away from direct sunlight
and dust. If the surface of a disc is soiled, dampen
a clean, soft cloth in a mild, neutral detergent solution
and clean it, wiping from the center to the edge.
Be sure never to touch the side without writing when
handling discs. Pick up discs by grasping the outer
edges or the edge of the hole and the outer edge.
Care of Your CD Player
The use of CD lens cleaner discs is not advised, due to
the risk of contaminating the lens of the CD optics
with lubricants internal to the CD mechanism.
Fixed Mast Antenna
Thefixed mast antenna can withstand most car washes
without being damaged. If the mast should ever
become slightly bent, you can straighten it out by hand.
If the mast is badly bent, as it might be by vandals,
you should replace it.
Check occasionally to be sure the mast is still tightened
to the cowl. If tightening is required, tighten by hand,
then with a wrench one quarter turn.
XM™Satellite Radio Antenna
System (United States Only)
Your XM™Satellite Radio antenna is located on the
roof of your vehicle. Keep this antenna clear of
snow and ice build up for clear radio reception.
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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. Your brakes may not have time to cool
between hard stops. Your 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 engine ever stops while you’re driving, brake
normally but don’t pump your brakes. If you do,
the pedal may get harder to push down. If your 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.Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there’s a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-35.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there’s 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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Remember: Anti-lock doesn’t 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 won’t 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 anti-lock brakes.
Using Anti-Lock
Don’t 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 anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Supplemental Brake Assist System
If your vehicle has vacuum assist power brakes, it is also
equipped with a supplemental brake assist system
that supplies additional vacuum to the vacuum brake
booster if engine vacuum is reduced. Under certain
conditions, the supplemental brake assist system may
run briey after starting your vehicle or when you
apply and release the brake pedal and it may continueto run even after you have removed your foot from the
brake pedal. When the supplemental brake assist
system is operating, you may hear a motor running or
feel a slight vibration in the steering wheel or brake
pedal. This indicates that the supplemental brake assist
system is working to supply additional vacuum for
your vacuum assist power brakes. This is a normal
operation of your brake system and does not require that
the brake system be serviced.
Each time you start your vehicle and accelerate to
10 mph, the supplemental brake assist system
will perform a self-diagnostic check of the system and
you may hear or feel the supplemental brake assist
motor run briey. While you are driving your vehicle, the
supplemental brake assist system monitors itself to
ensure that it is operating properly. If there is a problem
with the supplemental brake assist system, the
SERVICE BRAKE BOOSTER message will be displayed
on the Driver Information Center. SeeDIC Warnings
and Messages on page 3-51.
If your supplemental brake assist system runs every
time you apply and release the brake pedal or you notice
that the brake pedal has suddenly become much
harder to push and the vehicle takes longer to stop, you
should have your vehicle serviced as soon as possible.
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