1996 GMC SIERRA check engine

3. If your engine still won’t start (or starts but then
stops), wait
15 seconds and start over.
When the engine starts, let
go of the key and the
accelerator pedal.
I NOTICE:
Your engine is designed to work with the
electronics in your vehicle.
If you add electrical
parts or accessories,
you could change the way
the engine operates. Before adding electrical
equipment, check with your dealer.
If you don’t,
your engine might not perform properly.
If you ever have to have your vehicle towed, see
the part
of this manual that tells how to do it
without damaging your vehicle. See “Towing
Your Vehicle” in the Index.
Engine Coolant Heater (Option)
-
In very cold weather,
0°F (-18°C) or colder,
the engine coolant heater
can help.
You’ll get easier starting and better fuel economy during
engine warm-up. Usually, the coolant heater
should be
pl~~gged in a minimum of four hours prior to starting
your vehicle.
To use the coolant heater:
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded 110-volt AC outlet.
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NOTICE:
Driving with the parking brake on can cause
your rear brakes to overheat.
You may have
to replace them, and you could also damage
other parts of your vehicle. Always check to be
sure your parking brake is fully released before
you drive.
If you are towing a trailer and are parking on any hill,
see “Towing a Trailer” in the Index. That section shows
what
to do first to keep the trailer from moving.
If you have a 3500 HD model, it is recommended that
the propshaft mounted parking brake be burnished as
part of the new vehicle break-in. The parking brake will
work best after it has been burnished following these
instructions.
Make
10 stops, using the parking brake foot pedal, from
20 mph (32 km/h) about 2 1/2 miles (4 km) apart. In
between stops, drive the vehicle at 20 mph (32 km/h).
Shifting Into PARK (P) (Automatic
Trawrission
Models Only)
It can be dangerous to get out of your vehicle if
the shift lever
is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured.
To be sure your vehicle won’t move,
even when you’re on fairly level ground, use
the steps that follow. If you have four-wheel
drive and your transfer case is in NEUTRAL
(N)?
your vehicle will be free to roll, even if your shift
lever
is in PARK (P). So, be sure the transfer case
is in
a drive gear -- not in NEUTRAL (N). If
you’re pulling a trailer, see “Towing a Trailer’’
in the Index.
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Instrument Panel Cluster
CHECK GAGES
SERVICE ENGINE SOON ANTI
LOCK
TRIP loo 0 0 oolol 1 APPLY TO SHIFT FROM PARK
United
States version shown, Canada similar.
Your instrument cluster is designed to let you know at a glance how your vehicle is running. You'll know how
fast you're going, about how much fuel you have and many other things you'll need to
know to drive safely
and economically.
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Warning Lights, Gages and Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help
you
locate them.
Warning lights and gages can signal
that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save
you or
others from injury.
Warning lights come on when there may be
or is a
problem with one of your vehicle’s functions.
As you
will see in the details on the next few pages, some
warning lights come
on briefly when you start the
engine just
to let you know they’re working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one
of your vehicle’s functions. Often gages and
warning lights work together
to let you know when
there’s a problem with your vehicle. When
one of the warning lights comes on and stays on
when
you are driving, or when one of the gages shows
there may be a problem, check the section that
tells you
what to do about it. Please follow this manual’s advice.
Waiting to do repairs can be costly
-- and even
dangerous.
So please get to know your warning lights
and gages. They’re a big help.
Safety Belt Reminder Light
When the key is turned to RUN or START, a tone will
come on for about eight seconds to remind people
to
fasten their safety belts, unless the driver’s safety belt is
already buckled.
-
The safety belt light will
on for about 20 seconds,
also
come
on and stay
then
it will flash for about
belt is already buckled,
55 seconds. If the driver’s
neither the tone nor
the
light will come on.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows AIR BAG. 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 module,
the wiring and the diagnostic module. For more
information
on the air bag system, see “Air Bag” in
the Index.
AIR
BAG
You will see this light flash
for a few seconds when you
turn your ignition
to RUN
or START. Then the light
should go out. This means
the system is ready.
Charging System Indicator Light
If the air bag readiness light doesn’t come on when you
start your vehicle, or stays on, or comes on when you
are driving, your air bag system may not work properly.
Have your vehicle serviced right away. This
light 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 charging system. It could indicate a
problem with the alternator drive belt,
or some other
charging system problem. Have
it checked right away.
Driving while this light is on could drain your battery.
If
you must drive a short distance with this light on, it
helps to turn off all your accessories, such
as the radio
and air conditioner.
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Malfunction Indicator Lamp (Service
- ;ine Soon Light) (Gasoline Engine)
Your vehicle is equipped
with a computer which
monitors operation
of the
fuel, ignition and emission SERVICE
ENGINE
SOON
control systems.
This system
is called OBD I1 (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. (In Canada,
OBD TI is replaced by
Enhanced Diagnostics.) The
SERVICE ENGINE SOON
light comes on to indicate that there is a problem and
service
is required. Malfunctions often will be indicated
by the system before any problem
is apparent, which
may prevent more serious damage to your vehicle. This
system is
also designed to assist your service technician
in correctly diagnosing any malfunction.
I NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be as
good and your engine may not run as smoothly.
This could lead
to costly repairs that may not be
covered by your warranty.
This light should come on, as a check to show you it is
working, when the ignition is
on and the engine is not
running.
If the light doesn’t come on, have it repaired.
This light will also come
on during a malfunction in one
of two ways:
0 Light Flashing -- A misfire condition has been
detected.
A misfire increases vehicle emissions and
may damage
the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service
is required.
0 Light On Steady -- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
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Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel (see
"Fuel" in the Index). Poor fuel quality will cause your
engine
not to run as efficiently as designed. You may
notice this
as stalling after start-up, stalling when you
put the vehicle into gear, misfiring, hesitaIion on
acceleration or stumbling on acceleration. (These
conditions may go away once the engine
is warmed up.)
This will be detected by
the system and cause the light
to turn on.
If
you experience this condition, change the fuel brand
you use.
It will require at least one full tank of the
proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have
your dealer or qualified service center check the'
vehicle. Your dealer has the proper test equipment and
diagnostic
tools to fix any mechanical or electrical
problems
that may have developed.
Oil Pressure Gage
0 \ 80
The oil pressure gage shows
the engine oil pressure in psi
(pounds per square inch)
when the engine is running.
Canadian vehicles indicate pressure in
Wa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and
oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused
by a dangerously low oil level or some other problem
causing low oil pressure. Check your
oil as soon
as possible.
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/A CAUTION: l!,L- .
Don’t keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches 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 and
is not covered by your
warranty.
Shift Light
SHIFT
This light is used on some
models
with manual
transmissions.
The
SHIFT indicator light will help you get the best fuel
economy. See “Shift Light” or “Shift Speeds”
in this
section for more information.
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