1997 GMC SIERRA Owners Manual

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.
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.
I
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.
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.)
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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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If the Light Is Flashing If the Light Is On Steady
The following may prevent more serious damage to
your vehicle:
0 Reducing vehicle speed.
0 Avoiding hard accelerations.
0 Avoiding steep uphill grades.
0 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,
stup 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. You
may be able to correct the emission system
malfunction by considering the following:
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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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
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 some other problem
causing low oil pressure. Check your oil as soon
as possible.
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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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Fuel Gage
Eb"
The fuel gage, when the
ignition
is on, tells you
about how much fuel you
have left
in your tank.
The gage will first indicate EMPTY (E) before you are
out of fuel, and you should get more fuel as soon
as possible. Here are
four situations
you may experience with your
fuel gage. None of these indicate a problem w.ith the
fuel gage.
At the gas station, the fuel pump shuts off before the
gage reads
FULL (F).
It takes a little more or less fuel to fill up than the
fuel gage indicated. For example, the gage may have
indicated the tank was half full, but it actually took a
little more or less than half the tank's capacity to fill
the tank.
The gage moves a little when you turn a corner or
The gage doesn't go back to EMPTY (E) when you
speed up.
turn off the ignition.
If you have a diesel engine, see "Fuel Gage" in the
Diesel Engine Supplement.
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