1997 GMC SIERRA check engine light

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.
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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
also come on and stay on
for about
20 seconds,
then it will flash for about
55 seconds. If the driver’s
belt is already buckled,
neither the tone nor the
light will come on.
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
This light will come on
when you start your engine,
and it will
flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
engine or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for
a few
seconds when you turn the ignition key to
RUN. If the
light doesn’t come on then, have it fixed
so it will be
ready to warn you if there
is a problem.
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/I CAUTION: I
If the air bag readiness light ever comes on when
you have turned
off the air bag, it means that
something may be wrong with the air bag system.
The right front passenger’s
air bag could inflate
even though the switch is
off. If this ever
happens, don’t secure a rearfacing child
restraint in your vehicle until you have your
vehicle serviced.
Charging System Indicator Light
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 generator 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 the air conditioner.
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Malfunction Indicator Lamp (Service
Engine Soon Light) (Gasoline Engine)
SERVICE
ENGINE
SOON
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD
II (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 II 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.
This may prevent more serious
damage to your vehicle. This system is
also designed
to assist your service technician in correctly diagnosing
any malfunction.
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.
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, hesitation 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 one or more of these conditions,
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
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 kPa
(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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I !!i GL1U ION:
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.
Up Shift Light (If Equipped)
This light is used on
some models with
manual transmissions,
SHIFT
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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Daytime Running Lamps Indicator Light
:::O e..
This light goes on whenever
the DRL are
on.
Check Gages Light
I
CHECK
GAGES
This light will come on
briefly when
you are
starting the engine.
When it begins to get dark, the DRL indicator light is a
reminder
to turn on your headlamps.
If the light comes on and stays on while you are driving,
it could indicate a problem with your vehicle. It could be
a problem with your oil pressure, coolant temperature,
or some other problem. Check your various gages
to see
if they are
in the warning zones. If they are, have your
vehicle serviced right
away.
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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 Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). 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.
ANTI -
LOCK
If there’s a problem with the
anti-lock brake system, this
warning light will stay on.
See “Anti-Lock Brake
System Warning Light”
in the Index.
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