light GMC SIERRA DENALI 2003 Repair Manual

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 for five
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.
After you clean the player, press and hold the EJECT
button for five 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.
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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
The fixed 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.
XMTM Satellite Radio Antenna
System
Your XMTM 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.
DAB Radio Antenna System
Your DAB antenna is located on the roof of your
vehicle. Keep this antenna clear of snow and ice build
up for clear radio reception.
If your vehicle
is purchased in Canada and driven into
the United States the DAB radio antenna system
will not function. DAB radio reception is available in
Canada only.
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.
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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. See
Anti-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. Let’s
say the road is wet and you’re driving safely.
Suddenly, an animal jumps out in front of you.
You slam
on the brakes and continue braking. Here’s 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.
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The switch is located on the instrument panel.
2: In this mode the vehicle will operate like any other
vehicle with two wheel steering. If you want to use
2 wheel steering and your vehicle is not in this mode,
press the button until the
2 indicator, located to the right
of the
4 Wheel Steer button, lights up. If the 2 indicator
is flashing you will have to center the steering wheel
by turning it
to the left or right.
Your vehicle will return to
2 (two wheel steering) when
the transmission is shifted into NEUTRAL, for
example when entering a car wash.
4: In this mode all four wheels will help steer the
vehicle.
If you want to use 4 wheel steering, and your
vehicle is not in this mode, press the button, until
the
4 indicator, located to the right of the 4 Wheel Steer
button, lights up.
If the 4 indicator is flashing you will
have to center the steering wheel by turning it to the left
or right.
I
I
Slower Speeds (below 40 m.p.h./64 km/h)
At slower speeds the front and rear wheels will turn in
opposite directions. This helps the vehicle make
tighter turns, such as during parking, cornering and
turning into tight spaces.
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4-1 1

I
Higher Speeds (40 m.p.h./64 km/h and above)
J
At higher speeds the front and rear wheels will turn in
the same direction. This improves stability of the vehicle
during lane changes and sweeping turns.
(4 Wheel Steer tow mode): When towing a trailer
the
4 wheel steer tow mode provides enhanced
stability allowing the trailer to follow the path of the tow
vehicle more closely, especially during lane changes.
In this mode the system operates much like the
4 mode,
but is enhanced for trailer towing. It is recommended
for all types and weights
of trailers.
To engage the
4 wheel steer tow mode, press the 4
Wheel Steer button until the 4 and tow indicators light up
on the instrument panel.
If the tow indicator is flashing
you will have to center the steering wheel by turning it to
the left or right. While in the
4 wheel steer tow mode,
it is possible the steering wheel may be slightly
off
center. For more information, see Towing a Trailer on
page
4-5 I.
4-1 2

Car Washes for
QUADRASTEERTM Equipped Vehicles
Notice: Because your vehicle has a wider rear track
a small number
of older car washes may be too
narrow for your vehicle. Conveyor systems on some
automatic car washes may damage your vehicle.
Only use conveyor system car washes with 13-inch
(33 cm) wide conveyor rails and/or stationary
washes with at least 82 inches (208 cm) between the
rails. Before using the car wash check with the
manager.
13 in. 13 in.
(33 cm) (33 . 1. cm)
Off -Road Recovery
You may find that your right wheels have dropped off
the edge of a road onto the shoulder while you’re
driving.
I ,
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease
off the
accelerator and then,
if there is nothing in the way,
steer
so that your vehicle straddles the edge of
the pavement.
You can turn the steering wheel up to
one-quarter turn until the right front tire contacts
the pavement edge, Then turn your steering wheel to go
straight down the roadway.
4-1 3

Surface Obstacles: Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut or bump can startle
you
if you’re not prepared for them. Often these
obstacles are hidden by grass, bushes, snow or even
the rise and fall of the terrain itself. Here are some
things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill?
(There’s more discussion of these subjects later.)
Will you have to stop suddenly or change direction
quickly?
When you drive over obstacles or rough terrain, keep a
firm grip on the steering wheel. Ruts, toughs or other
surface features can jerk the wheel out of your hands
if
you’re not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground. If this happens,
even with one or two wheels, you can’t control
the vehicle as well or at all. Because you
will be on an unpaved surface, it’s
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or
signal lights. You have to use your own good judgment
about what is safe and what isn’t.
Drinking and driving can be very dangerous on any
road. And this is certainly true for off-road driving. At the
very time you need special alertness and driving
skills, your reflexes, perceptions and judgment can be
affected by even
a small amount of alcohol. You
could have a serious
- or even fatal - accident if you
drink and drive or ride with a driver who has been
drinking. See
Drunken Driving on page 4-2.
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Q: Suppose, after stalling, I try to back down the hill
A: Set the parking brake, put your 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.
and decide
I just can’t
do it. What should I do?
Driving Downhill
When off-roading takes you downhill, you’ll want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What’s the surface like? Smooth? Rough? Slippery?
Hard-packed dirt? Gravel?
0 Are there hidden surface obstacles? Ruts? Logs?
What’s at the bottom of the hill? Is there a hidden
Boulders?
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 your brakes
and they won’t hate to do all the work. Descend slowly,
keeping your vehicle under control at all times. Heavy
braking when going down a
h 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
A: Yes! These are important because if you ignore
driving
down a hill?
0
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’s not too
steep to drive down may be too steep to drive
across. You could roll over
if you don’t drive straight
down.
Never go downhill with the transmission in
NEUTRAL (N).
This is called “free-wheeling.” Your brakes will have
to do all the work and could overheat and fade.
4-24

Driving at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be impaired
- by
alcohol or drugs, with night vision problems, or by fatigue.
Here are some tips on night driving.
Drive defensively.
0 Don’t drink and drive.
0 Adjust your inside rearview mirror to reduce the
glare from headlamps behind you.
Since you can’t see as well, you may need to slow
down and keep more space between you and
other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light up only
so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off the road in a safe place
and rest.
No one can see as well at night as
in the daytime. But
as we get older these differences increase.
A
50-year-old driver may require at least twice as much
light to see the same thing at night as a 20-year-old.
What you do in the daytime can also affect your
night vision. For example,
if you spend the day in bright
sunshine you are wise to wear sunglasses. Your
eyes will have less trouble adjusting to night. But
if
you’re driving, don’t wear sunglasses at night. They may
cut down on glare from headlamps, but they also
make a lot of things invisible.
You can be temporarily blinded by approaching
headlamps. It can take a second
or two, or even several
seconds, for your eyes to re-adjust to the dark. When
you are faced with severe glare (as from a driver
who doesn’t lower the high beams, or a vehicle with
misaimed headlamps), slow down a little. Avoid staring
directly into the approaching headlamps.
4-29

Keep your windshield and all the glass on your vehicle
clean
- inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside of the glass
can build up a film caused by dust. Dirty glass makes
lights dazzle and flash more than clean glass would,
making the pupils of your eyes contract repeatedly.
Remember that your headlamps light up far less of a
roadway when you are in a turn or curve. Keep
your eyes moving; that way, it’s easier to pick out dimly
lighted objects. Just
as your headlamps should be
checked regularly for proper aim,
so should your eyes
be examined regularly. Some drivers suffer from
night blindness
- the inability to see in dim light - and
aren’t even aware of
it.
Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you can’t stop, accelerate or turn as well
because your tire-to-road traction isn’t as good as on
dry roads. And, if your tires don’t have much tread left,
you’ll get even less traction. It’s always wise to go
slower
and be cautious if rain starts to fall while you are
driving. The surface may get wet suddenly when your
reflexes are tuned for driving on dry pavement.
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