1997 GMC SIERRA service indicator

Electronic Transfer Case (If Equipped)
If your four-wheel-drive vehicle has the electronic
transfer case, the transfer case switches are below and
to
the left of the climate control system.
Use these switches to shift into and out
of four-wheel
drive. You can choose among three driving settings:
.
2HI: This setting is for driving in most street and
highway situations. Your front axle is not engaged
in
two-wheel drive.
4HI: This setting engages your front axle to help
drive your vehicle. Use
4HI when you need extra
traction, such as
on snowy or icy roads, or in most
off-road situations.
4LO: This setting also engages your front axle to give
you extra traction. You may never need
4LO. It sends
the maximum power to all four wheels. You might
choose
4LO if you were driving off-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the switches show you which setting
you are in. The indicator lights will come
on briefly
when you turn on the ignition and the last chosen setting
will stay on. If the lights do not come on, you should
take your vehicle in for service. An indicator light will
flash while shifting. It
will remain illuminated when
the shift is completed. If for some reason the transfer
cannot make a requested shift,
it will return to the last
chosen setting.
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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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Anti-Lock Brake System Warning Light
ANTI -
LOCK
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 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.
Engine Coolant Temperature Gage
Ill This gage shows the engine
1
*\\I‘
00
%,
0
260
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
(lOO°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 ( 125 “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
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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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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The cassette tape player is able to detect a broken tape.
Some cleaning cassettes may appear as
a broken tape. If
the cleaning cassette is ejected immediately from the
tape player, follow these steps:
1. Turn the radio off.
2. Turn the ignition on.
3. Press and hold the TAPE-AUX button until the tape
4. Insert the cleaning cassette and the radio will turn on
5. Eject the tape after the tape player has been cleaned.
When the cleaning cassette has been ejected, the broken
tape detection feature is active again.
symbol
flashes.
in cassette mode.
After you clean the player, press and hold EJECT for
five seconds to reset the CLN indicator. The radio will
display
--- to show the indicator was reset.
Cassettes are subject to wear and the sound quality
may degrade over time. Always make sure the cassette
tape is in good condition before you have your tape
player serviced.
Care of Your Compact Discs
Handle discs carefully. Store them in their original cases
or other protective cases and away from direct sunlight
and dust. If the surface of a disc is soiled, dampen a
clean, soft cloth in a mild, neutral detergent solution and
clean
it, wiping from the center to the edge.
Be sure never to touch the signal surface when handling
discs. Pick up discs by grasping the outer edges or the
edge of the hole and the outer edge.
Fixed Mast Antenna
The fixed mast antenna can withstand most car washes
without being damaged.
If the mast should ever become
slightly bent, you can straighten it
out by hand. If the
mast is badly bent, as it might be by vandals, you should
replace
it.
Check every once in a while to be sure the mast is still
tightened
to the cowl.
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Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your GM dealer before adding equipment to
the outside
of your vehicle.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System”
in the Diesel Engine
Supplement. For vehicles with gasoline engines, please
read this.
Use regular unleaded gasoline rated at
87 octane or
higher. At a minimum, it should meet specifications
ASTM D4814 in the United States and CGSB
3.5-M93
in Canada. Improved gasoline specifications have been
developed by
the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting
the AAMA
specification could provide improved driveability and
emission control system protection compared to
other gasolines. Be sure
the posted octane is at least 87. If
the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at
87 octane or higher and you
still hear heavy knocking, your engine needs service.
But don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a
hill. That’s normal,
and
you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated
on the underhood tune-up label),
it is designed to operate
on fuels that meet California
specifications. If such fuels are
not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily
on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp
on
your instrument panel may turn on andor your vehicle
may fail a smog-check test. If this occurs, return
to your
authorized GM dealer for diagnosis
to determine the
cause of failure. In the event it is determined that the
cause of
the condition is the type of fuels used, repairs
may not be covered by your warranty.
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