1998 GMC ENVOY service

Brake System Warning Light
When the ignition is on, the brake system warning light
will 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.)
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
it fixed so it will be ready
to warn you if there’s
a problem.
(0) (8> doesn’t come on then, have
BRAKE
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.
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Anti-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 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
This gage shows the engine
coolant temperature. If the
gage pointer moves into
the
red area, your engine is
too hot!
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions,
you should pull off the road, stop your
vehicle and turn off
the engine as soon as possible.
The “Problems on the Road” section
of this manual
shows you what to do. See “Engine Overheating”
in
the Index.
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Malfunction Indicator Lamp
(Service Engine Soon Light)
SERVICE
ENGINE
SOON
United States Canada
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 Gene.ration) and
is intended to
assure that emissions are at acceptable levels for the life
of the vehicle, helping to produce a cleaner
environment. 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.
a
a
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:
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 may be 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
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
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.
If the Light Is On Steady
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.
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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 gar, 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.
Engine 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 other problems causing low
oil pressure.
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I A CAUTION:
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
I NOTICE:
Damage to your engine from neglected oil
problems can be costly and
is not covered by
your warranty.
Security Warning Light
SECURITY
This light will come on
briefly when you turn the
key toward START. The
light will stay on until the
engine starts.
If the light flashes, the Passlock system has entered a
tamper mode.
If the vehicle fails to start, see “Passlock”
in the Index.
If the light comes on continuously while driving and
stays
on, there may be a problem with the Passlock
system. Your vehicle will not be protected by Passlock,
and you should see your dealer.
This light should also flash as you open
the door (if your
ignition is off).
This is a reminder to activate the
theft-deterrent system. See “Content Theft-Deterrent” in
the Index for more information.
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Service 4WD Light
SERVICE
4WD
This light should come on
briefly when you turn on the
ignition, as a check to show
you it is working.
The
SERVICE 4WD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage
to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
Check Gages Light
The CHECK GAGES light
CHECK
GAGES
will come on briefly when
you are starting the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil pressure
gages
to see if they are in the warning zones.
Gate Ajar Light
GATE
AJAR
This light will come on
briefly when
you are
starting the engine.
If it stays on, your liftgate
is ajar. Try closing the liftgate
again. Never drive with the liftgate even partially open.
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When using a scrubbing action, non-abrasive cleaning
cassette,
it is normal for the cassette to eject because
your unit is equipped with a cut tape detection feature
and
a cleaning cassette may appear as a broken tape. To
prevent the cleaning cassette from being ejected, use the
following steps.
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio off.
3. Press and hold the TAPE AUX button for five
seconds. The tape symbol on the display
will flash
for two seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer’s
recommended cleaning time.
When the cleaning cassette has been ejected, the cut tape
detection feature
is active again. You may
also choose a non-scrubbing action, wet-type
cleaner which uses a cassette
with a fabric belt to clean
the tape head. This type of cleaning cassette will not
eject on its own.
A non-scrubbing action cleaner may
not clean as thoroughly
as the scrubbing type cleaner.
The use of a non-scrubbing action, dry-type cleaning
cassette is not recommended.
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.
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