service indicator GMC ENVOY 1998 Owners Manual

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 one 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.
Shifting from 2HI to 4HI
Press and release the 4HI switch. This can be done at
any speed, and the front axle will lock automatically.
Shifting from 4HI to 2HI
Press and release the 2HI switch. This can be done at
any speed, and the front axle will unlock automatically.
Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4L0, the vehicle must be
stopped
or moving less than 3 mph (4.8 kmh) with the
transmission
in NEUTRAL (N). The preferred method
for shifting into 4LO is to
have your vehicle moving 1 to
2 mph (1.6 to 3.2 kmh). Press and release the 4LO
switch. You must wait for the 4LO indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
If the 4LO switch
is pressed when your vehicle is in
gear and/or moving,
the 4LO indicator light will flash
for
30 seconds and not complete the shift unless your
vehicle
is moving slower than 3 mph (4.8 kdh) and the
transmission is in NEUTRAL
(N).
If your transfer case does not shift into 4L0, your
transmission indicator switch may require adjustment.
With your transmission in NEUTRAL (N), press and
release the 4LO switch. While the 4LO indicator light
is
flashing, shift your transmission into PARK (P). Wait
until the 4LO indicator light remains illuminated before
shifting your transmission into gear. This will get you
into 4L0, but you should take your vehicle in for service
to restore normal operation.
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Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4H1 or 2H1, your vehicle must be
stopped or moving less than
3 mph (4.8 kdh) with the
transmission in NEUTRAL
(N). The preferred method
for shifting out of 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 kdh). Press and release the 4HI
switch.
You must wait for the 4H1 indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
If the 4HI switch is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light will flash for
30 seconds but not complete the shift unless the vehicle
is moving slower than 3 mph (4.8 kmh) and the
transmission
is in NEUTRAL (N).
If your transfer case does not shift into 4H1, your
transmission indicator switch may require adjustment.
With your transmission in NEUTRAL
(N), press and
release the 4HI switch. While the 4HI indicator light is
flashing, shift your transmission into PARK
(P). Wait
until the 4HI indicator light remains illuminated before
shifting your transmission into gear. This will get you
into 4H1, but you should take your vehicle
in for service
to restore normal operation.
Windows
Power Windows
The controls for the power windows are on each of the
side doors. The switches control
the windows when the
ignition is on or when Retained Accessory Power (RAP)
is present. (See “Retained Accessory Power” in the
Index.) The driver’s door has
a switch to control the
passenger windows as well.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows
the air bag symbol. 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.
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 Indicator Light
The charging system light
will come on briefly when
you turn on the ignition, but
’ the engine is not running,
as a check to show you it
is working.
It should go out once the engine
is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system.
It could indicate that
you have problems with
a generator drive belt, or
another electrical problem. Have
it checked right away.
Driving while this light
is on could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
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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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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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If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
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 and/or 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.
Some gasolines that are
not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does
not recommend the
use of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator lamp on your instrument panel
may turn
on. If this occurs, return to your authorized
GM dealer for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent deposits from forming
in your engine and fuel
system, allowing your emission control system to
function properly. Therefore, you should not have to add
anything to
the fuel. In addition, gasolines containing
oxygenates, such as ethers and ethanol, and
reformulated gasolines may be available in your area
to
help clean the air. General Motors recommends that you
use these gasolines
if they comply with the
specifications described earlier.
I NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don’t use it.
It can corrode
metal parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t be covered under your warranty.
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NOTICE:
0 Using the wrong fluid can badly damage
brake system parts. For example, just
a few
drops of mineral-based oil, such as engine
oil, in your brake system can damage brake
system parts
so badly that they’ll have to be
replaced. Don’t let someone put in the
wrong kind of fluid.
If you spill brake fluid on your vehicle’s
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on your vehicle.
If you do, wash it off
immediately. See “Appearance Care” in
the Index.
Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the brake
pads are worn and new pads are needed. The sound
may come and
go or be heard all the time your vehicle
is moving (except when you are pushim on the brake
pedal firmly).
A CAU‘
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result
in costly brake repair.
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When It’s Time for New Tires
One way to tell when it’s
time for new tires is to
check the treadwear
indicators, which will
appear when your tires have
only 1/16 inch (1.6 mm) or
less
of tread remaining.
You need a new tire if any of the following statements
are true:
0 You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.
0 The tire has a bump, bulge or split.
The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or location
of the damage.
Buying New Tires
To find out what kind and size of tires you need, look at
the Certificationmire label.
The tires installed
on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When
you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service
on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an
“MS”
(for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial)
as your original tires.
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Lamps ........................................ 2-36
Dome
...................................... 2-39
Exterior
.................................... 2-36
Front Reading
........................... 2.39. 2.43
Interior
..................................... 2-39
On Reminder
................................ 2-37
Leaving Your Vehicle
............................. 2-6
Leaving Your Vehicle
with the Engine Running ....... 2-22
Liftgate
........................................ 2-9
Manual Release
.............................. 2- 10
Remote Release .............................. 2- 10
Lighter ....................................... 2-49
Lights Air Bag Readiness
....................... 1-22, 2-63
Anti-Lock Brake System Warning
............ 2-66? 4-7
Brake System Warning
......................... 2-65
Charging System
............................. 2-63
CheckGages
................................ 2-71
Gate Ajar
................................... 2-7 I
LowFuel ................................... 2-72
Safety Belt Reminder
...................... 1-8.2-62
Security Warning
............................. 2-70
Service4WD
................................ 2-71
Service Engine Soon
.......................... 2-67
Loading Your Vehicle
........................... 4-40
Locking Rear Axle
.............................. 2-24
Lockout Prevention
.............................. 2-5
Lockout Switch
................................ 2-29
Locks
......................................... 2-4
Door
........................................ 2-4
Ignition Transmission Check
.................... 7-42
Key Lock Cylinder Service
..................... 7-40 Power Door
.................................. 2-5
Rear Door Security
............................. 2-5
Loss
of Control ................................ 4-13
LowFuelLight
................................ 2-72
Lubricants and Fluids
............................ 7-45
Lubrication Service
. Body ........................ 7-40
Luggagecarrier
................................ 2-48
Lumbar Controls
................................ 1-3
Maintenance Record ........................... 7-47
Maintenance Schedule
............................ 7-1
Owner Checks and Services ..................... 7-39
Periodic Maintenance Inspections
................ 7-43
Recommended Fluids and Lubricants
............. 7-45
Scheduled Maintenance Services
.................. 7-4
Long Trip/Highway
....................... 7-6.
7-27
Short TripKity
............................ 7-5. 7-7
Maintenance. Underbody
......................... 6-52
Malfunction Indicator Lamp ...................... 2-67
Manual Passenger’s Seat
.......................... 1-2
Methanol
...................................... 6-4
Mirrors
....................................... 2-40
Convex Outside
.............................. 2-42
Electrocho~nic Day/Night Inside Rearview
......... 2-40
Heated Outside Rearview
....................... 2-42
Illuminated Visor Vanity
....................... 2-50
Outside
..................................... 2-42
Model Reference
................................. vi
Mountain Roads ................................ 4-34
Multifunction Lever
............................. 2-30
Maintenance When Trailer Towing
................. 4-51
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