1993 GMC SIERRA service

Malfunction Indicator Lamp (Service Engine Soon Light)
I
SERVICE
EF_'31NE
SOON
K2329
A computer monitors operation of your fuel, ignition, and emission control
systems. This light should come on when the ignition is on bu\
t the engine is not running, as a check to show you it is working. If it does not come on at
all, have it fixed right away.
If it stays on, or comes on while you are driving,
the computer is indicating that you have a problem. You should take your
vehicle in for service soon.
NOTICE
E
If you keep driving your vehicle with this light on, after awhile the emission
controls won't work well, your fuel economy won't be as good, and your
engine may not run as smoothly. This could lead
to costly repairs not
covered by your warranty.
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Features & Controls
A reading in the low pressure zone may be caused by a dangerously low oil
level or other problem causing low oil pressure. Check your oil as soon as
possible.
bnu I IUIY
+ Don’t keep driving if the oil pressure is low. If you do, your engine
can become
so hot that it catches on fire. You or others could be
burned. Check your oil as soon as possible and have your vehicle
serviced.
I NOTICE
Damage to your engine from neglected oil problems can be costly anc
not covered by your warranty.
Voltmeter
Standard Cluster Tachometer Cluster
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A
K2336
When your engine is not running, but the ignition is on (in the Run position),
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 ope\
rating range.
Readings
in either warning zone indicate a possible problem in the electrical
system.
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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, and have the vehicle
serviced as soon as possible.
Camper Wiring Harness
The optional 5-wire harness is stored in’ the front stake pocket on the driver’s
side of’ the bed. The harness has no connector, and should be wired by\
a
qualified electrical service person.
It must be routed out of your vehicle and
securely attached
so that it won’t be pulled or rubbed while you’re using it.
Store the -harness in its original place. Wrap the harness together and tie it
neatly
so it won3 be damaged.
The optional 7-wire harness
is stored under your vehicle along the rear frame
crossmember. The harness has a’
30 amp. in-line fused battery feed wire and
no connector, and should be wired by a qualified electrical se\
rvice person.
Securely attach
the harness to the trailer, then tape or strap it to your
vehicle’s frame rail. Be sure you leave it loose enough
so the wiring won’t
bind
or break when turning with the trailer, but not so loose that it drags on
the ground.
Store the harness in its original position. Wrap the harness together and tie it
neatly so it won’t be damaged. ,
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Comfort Contrors & Audio Systems
Care of Your Cassette Tape PIayer
A tape player that is not cleaned regularly can cause reduced so\
und 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 cause failure of\
the tape player.
Your tape player should be cleaned regularly each month
or after 15 hours of
use. If you notice a reduction in sound quality, try a known good cassette to
see
if the tape or the player is at fault. If this other cassette has no
improvement in sound quality, clean the tape player.
Clean your tape player with a wiping-action, non abrasive clean\
ing cassette,
and follow the directions provided with
it.
Cassettes are subject to wear and the sound quality may degrad\
e over time.
Always make sure that the cassette tape is in good condition \
before you
have your tape player serviced.
K1313
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.
Check every once in a while to be sure the mast is still tightened to the
fender.
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Your Driving and the Road
LOW
SHOULDER
WORKERS
AHEAD FLAGGER
AHEAD
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ORANGE indicates road construction or maintenance. You’ll want to slow
down when you see an orange sign, as part of the road may be closed off
or torn up. And there may be workers and maintenance vehicles around, too.
II WES EAST
HOSPITAL
EX11 1
AM402008
GREEN is used to guide the driver. Green signs may indicate upcoming
freeway exits or
show the direction you should turn to reach a particular
place.
INFORMATION
I
BLUE signs with white letters show motorists’ services.
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Your Driving and fhe Road
Brake System Warning Light
K2325
This light appears on your instrument cluster to warn you if your regular
braking’ system needs service. See “Brake System Warning L\
ight” in the
Index.
Disc Brake Wear Indicators
If you have a C 3500 HD Model, it has four-wheel disc brakes. Disc brake
pads have built-in wear indicators that make a high-pitched war\
ning sound
when the brake pads are worn and new pads are needed. The so\
und m’ay
come and go or be heard all the time your vehicle is moving (except \
when
you are pushing on the brake pedal firmly).
1 CAUTION
The brake wear warning sound means that sooner or later your
hear the brake wear warning sound, have your vehicle serviced. \
5 brakes won’t work well. That could lead to an accident. When you I ~
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brakes are first applied or lightly applied. This does not mea\
n something is
wrong with your brakes.
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may not realize the surface is slippery until your vehicle is skidding. Learn to
recognize warning clues-such as enough water, ice
or packed snow on the
road to make a “mirrored surface’’-and slow down when you have \
any
doubt.
Remember: the rear wheel anti-lock braking system (RWAL) helps\
avoid only
a rear braking skid. In a braking skid (where the front wheels are no longer
rolling), release enough pressure on the brakes to get the front wheels rolling
again. This restores steering control. Push the brake pedal dow\
n steadily
when you have to stop suddenly.
As long as the front wheels are rolling, you
will have steering control. Steer the way you want to go.
Off-Road Driving with Your FourcWheel
Drive Vehicle
This off-road guide is for vehicles that have four-wheel drive. Also, see
“Anti-lock Brakes” in the Index.
If your vehicle doesn’t have four-wheel drive,
you shouldn’t drive off-road unless you’re on a level, so\
lid surface.
Off-road driving can be great fun. But it does have some defi\
nite hazards.
The greatest
of these is the terrain itself.
“Off-roading” means you’ve left the great North American\
road system behind.
Traffic lanes aren’t marked. Curves aren’t banked. There a\
re no road signs.
Surfaces can be slippery, rough, uphill
or downhill. In short, you’ve gone right
back
to nature.
Off-road driving involves some new skills. And that’s why it’s very important
that you read this guide. You’ll find many driving tips and suggestions. These
will help make your off-road driving safer and more enjoyable. \
Before You Go Off-Roading
There are some things to do before you go out. For example, be sure to
have all necessary maintenance and service work done. Be sure \
you read all
the information about your four-wheel drive vehicle in this manual.
Is there
enough fuel?
Is the spare tire fully inflated? Are the fluid levels up where
they should be? What are the local laws that apply to off-roa\
ding where you’ll be driving?
If you don’t know, you should check with law enforcement people\

in the area. Will you be on someone’s private land?
If so, be sure to get the
necessary permission.
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Your Driving and the Road
After Off-Road Driving
Remove any brush or debris that has collected on the underbody\
, chassis, or
under the hood. These accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings cleaned\
and checked. These substances can cause glazing and uneven braking. Check th\
e body
structure, steering, suspension, wheels, tires, and exhaust syste\
m for damage.
Also, check the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due
to off-road use. Refer to
Section
7 for additional information.
Driving at Night
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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. Remember, this is the most dangerous time.
Don’t drink and drive (See “Drunken Driving” in the Index for more on
this problem).
Adjust your inside rear view mirror to reduce the glare from headlights
Since you can’t see as well, you may need to slow down and keep
behind
you.
more space between you and other vehicles. It’s hard
to tell how fast
the vehicle ahead is going just
by looking at its taillights.
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