1998 GMC ENVOY Owners Manual

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.
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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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Fuel Gage
@ FUEL ONLY
When the ignition is on,
the fuel gage tells you
about how much fuel you
have remaining.
Here are four things that some
owners ask about. None
of these
show a problem with your fuel gage:
0 At the gas station, the gas pump shuts off before the
u gage reads FULL (F).
0 It takes a little more or less fuel to fill up than the
gage indicated. For example, the gage
may have
indicated the tank
was half full, but it ~t~ally 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.
Low Fuel Light
This light comes on when
the fuel tank
is low on fuel.
LOW
FUEL
TO turn it off, add fuel to the fuel tank. See “Fuel” in
the Index.
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Section 3 Comfort Controls and Audio Systems
In this section, you’ll find out how to operate the comfort control and audio systems offered with your vehicle. Be
sure to read about the particular systems supplied with your vehicle.
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Comfort Controls Electronic Climate Control System
Air Conditioning
Heating
Ventilation System
Defogging and Defrosting
Rear Window Defogger
Audio Systems Setting the Clock
AM-FM Stereo with Cassette
Tape Player 3- 12
3- 16
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AM-FM Stereo with Compact Disc Player
(If Equipped)
Rear Seat Audio (RSA)
Console-Mounted CD Changer
Theft-Deterrent Feature
Understanding Radio Reception
Tips About Your Audio System
Care of Your Cassette Tape Player
Care
of Your Compact Discs
Care of Your Compact Disc Player
Fixed Mast Antenna
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Comfort Controls
With this system, you can control the heating, cooling
and ventilation in your vehicle.
AUTO: If the knob is in AUTO, the fan speed will vary
as the system maintains
the selected temperature.
Temperature Knob
Electronic Climate Control System
Fan Control
The knob on the left side of the climate control panel
controls the fan speed.
To manually increase airflow,
move the knob to the right. To manually decrease
airflow, move it to the left.
OFF: If the knob is in OFF, outside air will still enter
the vehicle, and will be directed based on the position of
the mode knob. The middle knob
on the control panel lets
you select the
desired air temperature in your vehicle. This knob will
allow you
to adjust the interior air temperature
independently of the function knob setting. Turn the
knob to the right toward 82 for warmer air. Turn the
knob to the left toward
66 for cooler air.
Full Hot: If you turn the temperature knob past 82°F
(2SoC), the system will
go into the “full hot” mode. The
system will remain at that maximum heating setting and
the
fan will blow at the speed the fan knob is set to. If
the fan is in AUTO, it will run at full speed.
Full Cold: If you turn the temperature knob past 66°F
(19” C), the system will go into the “full cold” mode.
The system will remain at that maximum cooling setting
and the fan will blow at the speed the fan knob is set to.
If the fan is in AUTO, it will run at full speed.
Choosing either maximum setting will not cause the
system to heat or cool any faster.
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Mode Knob - Automatic Operation
The right knob on the control panel allows you to
choose the direction of air delivery. When the system is
set for automatic operation, sensors will control the air
delivery mode.
Air will come primarily from the floor or
instrument panel outlets, with some air directed to the
windshield to prevent fogging.
When the system is in AUTO mode, the air conditioning
light will turn on, and the recirculation and outside air
lights turn
off. With the system in full auto control
(both the fan and mode knobs
in AUTO), you still have
the ability to override any function. However,
continually overriding the outside air or the
A/C
compressor will limit the ability of the system to cool
the vehicle quickly.
If you push a button for a function which is nor
available, the light next to that button will flash three
times to alert you that it’s not available.
To find your comfort zone, start with the
74°F (23 O C)
setting and allow about 20 minutes for the system to
adjust the temperature if necessary.
With the automatic setting, the
air conditioning compressor
automatically cycles when needed to cool the
air. In cold
weather, when the system senses the need for heat, the
airflow
will be directed out the floor outlets. As the interior temperature approaches the desired setting, the
blower speed will decrease. To maintain interior comfort,
the &ow will adjust between the instrument panel
air
outlets and floor outlets. On bright sunny days in cool
weather, the alrflow may come out
of the air conditioning
and floor outlets (bi-level mode) to maintain comfort and
prevent stuffiiess.
To avoid blowing cold
air in cold weather, the system will
delay turning on the fan until warm
air is available. The
length of delay depends on the outside
air temperature,
engine coolant temperature or the time since the engine was last started.
As the coolant warms up, the blower fan
speed will gradually increase and
air will flow from the
heater outlets, with some airflow to
the windshield to
prevent fogging under most normal conditions.
If your vehicle is sitting out on a warm day and you
have the fan set on AUTO, the air will first flow out of
the floor air outlets
for a few seconds. That is normal.
This is to expel hot air from the air outlets.
As the air is
cooled, the airflow will move through the
air
conditioning outlets.
Be careful not to put anything over the solar sensor
located around the center of the instrument panel.
This sensor is used by the automatic system to
regulate temperature.
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