1996 GMC SIERRA Owners Manual

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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Voltmeter
I When your engine is not
running, but the ignition is
in the RUN position, this
gage shows your battery’s
9 19 state of charge in DC volts.
n
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
operating range. Readings
in the low warning zone
may occur when a
large number of electrical accessories are operating
in
the vehicle and the engine is left at an idle for an
extended period. This condition
is normal since the
charging system
is not able to provide full power at
engine idle.
As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow
the charging system to create maximum power.
You can only drive for a short time
with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings
in either warning zone indicate a possible
problem
in the electrical system. Have the vehicle
serviced
as soon as possible.
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Brake System Warning Light r
Your vehicle’s hydraulic brake system is divided into
two
parts. If one part isn’t working, the other part can
still work and stop you. For good braking, though, you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
BRAKE
This light should come
on briefly when
you turn
the ignition key to
RUN.
If it doesn’t come on then,
have
it fixed so it will be
ready to
warn you if there’s
a problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the floor.
It may take longer to stop. If
the light is still on, have the
vehicle towed for service. (See “Towing Your Vehicle”
in the Index.)
I! CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light
is still on after you’ve
pulled
off the road and stopped carefully, have
the vehicle towed for service.
When the ignition is on, the brake system warning light
will also come on when you set your parking brake. The
light will stay on if your parking brake doesn’t release
fully.
If it stays on after your parking brake is fully
released,
it means you have a brake problem.
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ANTI -
LOCK
Qnti-Lock Brake System Warning Light
With the anti-lock brake.
system, this light will come
on when
you start your
engine and may stay on
for several seconds.
That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service.
If the regular brake system
warning light isn’t on,
you still have brakes, but you
don’t have anti-lock brakes.
If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there’s
a problem with your regular brakes. See
“Brake System Warning Light” earlier
in this part.
The anti-lock brake system warning light should come
on briefly 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.
Engine Coolant Temperature Gage
I This gage shows the engine
~ coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F
(100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 260°F ( 125 “C) mark. If the
gage reaches the 260°F
(I 25 “C) mark, it indicates that
the cooling system is working beyond its capacity.
In “Problems
on the Road,” this manual shows what to
do. See “Engine Overheating” in the Index.
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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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If the Light Is Flashing If the Light Is On Steady
The following may prevent more serious damage to
your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
0 If towing a trailer, reduce the amount of cargo being
hauled
as soon as it is possible.
If the light stops flashing and remains
on steady, see “If
the Light
Is On Steady” following.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Put your vehicle in PARK (P). Turn the
key off, wait at least
10 seconds and restart the engine.
If the light remains
on steady, see “If the Light Is On
Steady” following.
If the light is still flashing follow the
previous steps, and drive the vehicle
to your dealer or
qualified service center for service.
You may be able to correct the emission system
malfunction by considering the following:
Did you just put fuel
into your vehicle?
If so7 reinstall the fuel cap, making sure to fully install
the cap. The diagnostic system can determine if the fuel
cap has been left off or improperly installed. This will
allow fuel to evaporate into
the atmosphere. A few
driving trips should turn the light off.
Did
you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will
usually be corrected when the electrical system
dries out.
A few driving trips should turn the light off.
Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the fuel line causing a misfire. The
system can detect this. Adding fuel should correct this
condition. Make
sure to install the fuel cap properly. it
will take a few driving trips to turn the light off.
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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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