1993 GMC SIERRA Index

GLOW PLUGS Light
I--
GLOW
PLUGS
K2337
Your diesel engine has a special starting system. An instrument\
panel GLOW
PLUGS light tells you when the engine is ready to be started. It is at the
upper right
of your cluster. For more details, see “Starting Your Diesel
Engine” in the Index.
Low Coolant Warning Light
LOW
K2327
If you have a diesel engine, you have a low coolant warning ligh\
t. If this light
comes on, your system is
low on coolant and the engine may overheat. See
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Features & Controls
“Engine Coolant’’ in the Index and have your vehicle s\
erviced as soon as
you can.
Charging System Light
K2328
The red charging system light is located at the upper right hand corner of
your instrument cluster. It should come on briefly when you turn on the
ignition, before starting the engine, as a check to show you it is working.
After the engine starts, the light should
go out. If it stays on, or comes on
while you are driving, you may have a problem with your elect\
rical charging system. It could indicate that you have a loose alternator drive belt, or\
that
you have some other electrical problem. Have it checked right away. Driving
while this light is on could drain your battery.
If you must drive a short distance with the light on, be certain to turn off all
your accessories, such as the radio and air conditioner.
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Features & Controls
Listed are four situations you may experience with your fuel g\
age:
At the gas station, the fuel pump shuts off before the gage reads full.
It takes a little more or less fuel to fill up than the fuel gage indicated.
For example, the gage may have indicated the tank was half fu\
ll, but
it
actually took a little more or less than half the tank's capa\
city to fill the
tank.
The gage moves a little when you turn a corner or speed up. \
The gage doesn't go back to empty when you turn off the ignition.
None of these indicate a problem with the fuel gage.
For information on how to
fill your fuel tank see "Fuel-Filling Your Tank" in
the Index.
For your fuel tank capacity, see "Fuel-Tank Capacity"
in the Index.
Engine Coolant Temperature Gage
760
K2334
This gage shows the engine coolant temperature. If the gage pointer moves
into the red area, about 260°F
(145°C) or more, your engine is too hot! It
means that your engine coolant has overheated.
If you have been operating
your vehicle under normal operating conditions, you should pull \
off the road,
stop your vehicle and turn
off the engine as soon as possible.
Hot Coolant Can Burn You Badly!
In "Problems on the Road", this manual shows what to do. See \
"Engine
Overheating" in the Index.
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Heater Output
Optional Engine Block Heater
If your engine is equipped with an optional engine block heater, you can use
it during initial start-up in cold weather (20”F,
-8”C, or lower) to help heat the
passenger compartment faster. Because an engine block heater war\
ms the
engine coolant, your vehicle’s heating system can provide som\
e heat as soon
as you start the engine.
The use
of an engine block heater also reduces the time it takes for the
engine to reach normal operating temperature, and shortens the time it takes
the heater to reach full output. For more information, See “Engine Block
Heater” in the Index.
Diesel Engine
If you idle your diesel engine for a long time when it’s cold\
outside, your
heater may blow out cool air. This is normal. When you increase the \
engine
speed, your heater should blow out warmer air.
If it doesn’t, your coolant
level may be
low. See “Engine Coolant’’ in the Index to find out how to
check your coolant level.
Electronic HeatingAir Conditioning System
Function Display
K2305
If your vehicle has air conditioning, your heating/air conditioning \
system will
look like this.
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Pavement Markings
NO PASSING ZONE
AM40201 6
Pavement markings add to traffic signs and signals. They give information to
drivers without taking attention from the roadway. A solid yellow line on your
side
of the road or lane means “don’t cross.”
Your Own Signals
Drivers signal to others, too. It’s not only more polite, it’s safer to let other
drivers know what you are doing. And in some places the law requires driver
signals.
Turn and lane change signals: Always signal when you plan to turn or
change lanes.
If necessary, you can use hand signals out the window: Left arm \
straight out
for a left turn, down for
slow or about-to-stop, and up for a right turn.
Slowing down: If time allows, tap the brake pedal once or twice in advance
of slowing or stopping. This warns the driver behind you.
Disabled: Your four-way flashers signal that your vehicle is disabled or is a
hazard. See “Hazard Warning Flasher” in the Index.
Traffic Officer
The traffic police officer is also a source of important informaaon. The officer’s
signals govern, no matter what the traffic lights or other sig\
ns say.
The next part discusses some of the road conditions you may e\
ncounter.
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Your Driving and the Road
Defensive Driving
The best advice anyone can give about driving is: Drive defens\
ively. Please start with a very important safety device in your vehicle: Buckle up,
(See “Safety Belts” in the Index.)
Defensive driving really means “be ready for anything.” On\
city streets, rural
roads, or freeways, it means “always expect the unexpected.’’
Assume that pedestrians or other drivers are going to be carel\
ess and make mistakes. Anticipate what they might
do. Be ready for their mistakes.
Expect children to dash out from behind parked cars, often fol\
lowed by other
children. Expect occupants in parked cars to open doors into traffic. Watch for
movement
in parked cars-someone may be about to open a door,
Expect other drivers to run stop signs when you are on a through street, Be
ready to brake
if necessary as you go through intersections. You may not
have to use the brake, but
if you do, you will be ready,
If you’re driving through a shopping center parking lot where there are
well-marked lanes, directional arrows, and designated parking are\
as, expect
some drivers to ignore all these markings and dash straight to\
ward one part
of the lot.
Pedestrians can be careless. Watch for them. In general, you must give way
to pedestrians even
if you know you have the right of way.
Rear-end collisions are about the most preventable of accidents. Yet they are
common. Allow enough following distance.
It’s the best defensive driving
maneuver, in both city and rural driving. You never know when the vehicle in
front of you is going to brake or turn suddenly.
Here’s a final bit of information about defensive driving. The most dangerous
time for driving in the
US. is very early on Sunday morning. In fact, GM
Research studies show that the most and the least dangerous times for
driving, every week, fall on the same day. That day is Sunday. The most
dangerous time is Sunday
3 a.m. to 4 a.m. The safest time is Sunday from
10 a.m. to 11 a.m. Driving the same distance on a Sunday at 3 a.m. isn’t
just a little more dangerous than it
is at 10 a.m. It’s about 134 times more
dangerous.
That leads to the next part.
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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 ~
I 1
i
~ i
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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