1997 CHEVROLET TAHOE service

Downloaded from www.Manualslib.com manuals search engine 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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Downloaded from www.Manualslib.com manuals search engine 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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Downloaded from www.Manualslib.com manuals search engine Brake System Warning Light
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.)
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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Downloaded from www.Manualslib.com manuals search engine Anti-Lock Brake System Warning Light
With the anti-lock brake
system, this light will come
ANTI -
LOCK
on when you start your
engine and may stay on for
several seconds.
That’s normal.
Engine Coolant Temperature Gage
This gage shows the engine
coolant temperature.
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 section.
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.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read
2 10 OF ( 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 OF( 160” C) mark. If the
gage reaches the
260”F( 160°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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Downloaded from www.Manualslib.com manuals search engine 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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Downloaded from www.Manualslib.com manuals search engine If the Light Is Flashing If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
The following
may prevent more serious damage to
your vehicle:
0 Reducing vehicle speed.
Avoiding hard accelerations.
0 Avoiding steep uphill grades.
If you are 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. Find a safe place to park your vehicle.
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. Did
you recently put fuel into your vehicle?
If
so, 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.
A loose or
missing fuel cap will allow fuel to evaporate into the
atmosphere. A few driving trips with the cap properly
installed 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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Downloaded from www.Manualslib.com manuals search engine 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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Downloaded from www.Manualslib.com manuals search engine 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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