1996 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.
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
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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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Daytime Running Lamps Indicator Light Check Gages Light
This light goes on whenever
the DRL are on.
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 w.hile 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
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.
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
ANTI -
LOCK
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I /1 CAJTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly
CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can’t see it or smell it,
so you might not
know it is
in your vehicle. Clear away snow from
around the base
of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow doesn’t collect there.
Open a window just a little on the side of the
vehicle that’s away from the wind. This will help
keep
CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery (or batteries) charged.
You will need a
well-charged battery (or batteries) to restart the vehicle,
and possibly for signaling later
on with your headlamps.
Let the heater run for awhile.
If
you have a diesel engine, you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start the engine again and repeat this
only
when you feel really uncomfortable from the cold. But
do it as little
as possible. Preserve the fuel as long as you
can. To help keep warm, you can get out of the vehicle
and do some fairly vigorous exercises every half hour or
so until help comes.
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