check engine light CHEVROLET SUBURBAN 1997 Owners Manual

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
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.
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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
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.
Charging System Warning Light
The charging system
warning light should come
on briefly when you turn on
the ignition, before starting
the engine, as a check to
show you it is working.
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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.
Voltmeter
9 19
When your engine is not
running, but the ignition is
in the RUN position, this
gage shows your battery's
state of charge in
DC volts. 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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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 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 I1 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.
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, 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
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 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 other problem causing low
oil pressure. Check your oil as soon as possible.
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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.
Daytime Running Lamps (DRL)
Indicator Light
:::o 0.0
This light will go on
whenever the DRL are on.
When it begins to get
dark, the DRL indicator light is a
reminder to turn on your headlamps.
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Check Gages Light Headlamp High-Beam Indicator Light
CHECK
GAGES
This light will come on
briefly when you are
starting the engine. The
high-beam indicator is
on whenever you use your
high-beam headlamps. For
more details about high
beams, see “Headlamp
HighLow Beam Changer”
earlier in this section.
If the light comes on and stays on while
YOU are driving, Turn Signal and Lane Change
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
signal a turn
or lane change.
vehicle serviced right
away. come on whenever
you
if they are in the warning zones. If they are, have your The signal indicator
will
See “Turn Signal and Lane
Change Indicator” earlier in
Indicator Lights
this section.
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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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You can run the engine to keep warm, but be careful.
I_
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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15
16
Fuse/Circuit Breaker Usage
14 4WD Indicator, Cluster, Front and
Rear Comfort Controls, Instrument
Switches, Radio Illumination,
Chime Module
DRL Relay, Fog Lamp Relay
17
18
19
20
21
22
23
24
A
B Front and Rear Turn Signals,
Back-up
Lamps, BTSI Solenoid
Radio (Ignition)
4WALNCM, ABS, Cruise Control
Radio (Battery)
PRNDL, Automatic Transmission, Speedometer, Check Gages,
Warning Lights
Variable Effort Steering
Not Used
Rear Wiper, Rear Washer Pump
Front Axle, 4WD Indicator Lamp,
TP2 Relay (Gasoline Engine)
Power Door Lock, Six-Way Power
Seat, Keyless Entry Module
Power Windows
Underhood Fuse/Relay Center
The underhood fusehelay center is located in the rear of
the engine compartment near the brake fluid reservoir.
Move the retainer clips for the cover to access the
fuse block.
You can remove fuses with a fuse extractor. The fuse
extractor is mounted to the interior fuse block. To
remove fuses if you don't have a fuse extractor, hold the
end of the fuse between your thumb and index finger
and pull straight out.
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