1998 GMC ENVOY lights

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.
3-3
I
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Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain.
You need to be familiar with the telrain and its
many different features. Here are some things to consider.
S~lr$uce Conditions. Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle
in different
ways. Depending upon the kind of surface
you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction and longer
braking distances.
Su$ace Obstucles . Unseen or hidden obstacles can be
hazardous.
A rock, log, hole, rut or bump can startle you if
you're not prepared for them. Often these obstacles are
hidden by grass, bushes, snow
or even the rise and fall of
the terrain itself. Here are
some things to consider:
0 Is the path ahead clear'?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill? (There's
more discussion of these subjects later.)
Will you have to stop suddenly or change
direction quickly'? When you
drive over obstacles or rough terrain, keep
a
firm grip on the steering wheel. Ruts, troughs or other
surhce features can jerk the wheel out
of your hands if
you're not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground.
If this happens, even
with one or two wheels, you can't control the vehicle as
well or at all.
Because you
will be on an unpaved surface, it's
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or signal
lights.
You have to use your own good judgment about
what is safe and what isn't.
Drinking and driving can be very dangerous
on any
road. And this is certainly true for off-road driving. At
the very time
you need special alertness and driving
skills, your reflexes, perceptions and judgment can be
affected by even
a small amount of alcohol. You could
have a serious
-- or even fatal -- accident if you drink
and drive or ride with a driver who has been drinking.
See "Drunken Driving"
in the Index.
4-18
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You can be temporarily blinded by approaching
headlamps. It can take
a second or two, or even several
seconds,
for your eyes to readjust to the dark. When you
are faced with severe glare
(as from a driver who
doesn’t lower the high beams, or a vehicle with
misaimed headlamps), slow down a little. Avoid staring
directly into the approaching headlarnps.
Keep your windshield and all the
glass oi=ryour vehicle
clean
-- inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside
of the glass
can build up
a film caused by dust. Dirty glass makes
lights dazzle and flash more than clean glass would,
making
the pupils of your eyes contract repeatedly.
Remember that your headlamps light
up far less of a
roadway when you are in a turn or curve. Keep your
eyes moving; that way, it’s easier to pick out dimly
lighted objects. Just
as your headlamps should be
checked regularly for proper
aim, so should your eyes
be examined regularly. Some drivers suffer from night
blindness
-- the inability to see in dim light -- and aren’t
even aware
of it.
Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you can‘t stop, accelerate or turn
as well because
your tire-to-road traction isn‘t as good
as on dry roads.
And,
if your tires don’t have much tread left, you’ll get
even
less traction. It’s always wise to go slower and be
cautious
if rain starts to fall while you are driving. The
surface may get wet suddenly when your reflexes are
tuned for driving
on dry pavement.
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A 50/50 mixture of water and DEX-COOL@ coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129°C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you use
only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
0- at
30,000 miles (50 000 km) or 24 months,
whichever occurs
first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this mixture,
you don’t need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use
a 50/50 mixture of clean water and
DEX-COOL@ coolant.
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FuseKircuit Usage
Breaker
2
3
4
8
9
10
11
12 Cigarette
Lighter, Data
Link Connector
Cruise Control Module and
Switch, Body Control Module,
Heated Seats
Gages, Body Control Module,
Instrument Panel Cluster
Interior Lights
Not Used
Power Outside Mirror, Power
Lock Relay
Courtesy Lamps, Battery
Run-Down Protection
Not Used
Turn Signal
Cluster, Engine Control Module
Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
FuseKircuit
Breaker
13
14
15
16
17
18
19
20
21
22
23
24
Usage
Auxiliary Power
Power Locks Motor
4WD Switch, Engine Controls (VCM, PCM, Transmission)
Air Bag
Front Wiper
Not Used
Radio Battery
Amplifier
HVAC
I (Automatic), HVAC
Sensors (Automatic)
Anti-Lock Brakes
Rear Wiper
Radio, Ignition
6-57
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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
9-6
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Tires (Continued)
Uniform Quality Grading
. . . . . . . . . . . . . . . . . . . . . . . 6-41
Wear Indicators
. . . . . . . . . . . . . . . . . . . . , . . . . . . . . . 6-40
When It’s Time for New
. . . . . . . . . . . . . . . . . . . . . . 6-40
TopStrap
..................................... 1-43
TorqueLock
.,..................................2-23
Torque, Wheel Nut . . . . . . . . . . . . . . . . . . . . . . . . . 5-29,6-60
Towing a Trailer
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-43
Towing, Recreational Vehicle
. . . . . . . . . . . . . . . . . . . . . 4-39
Towing Your Vehicle
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Trailer Brakes
.....................................4-47
Driving on Grades . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-50
Driving with a Trailer . . . . . . . . . , , . . . . . . . . . . . . . . . 4-48
Hitches
.........................................
Maintenance When Towing . . . . . . . . . . . . . . . . . . . . . 4-5 1
Parking on Hills . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . 4-50
Safety Chains
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-47
Tongueweight
...............................4-45
Total Weight on Tires . . . . , . . . . . . . . . . . . . . . . . . . . . 4-46
Towing
.........................................
TurnSignals .....................................
Weight .....................................4-45
Wiring Harness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-52
Transfer Case
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Electronic
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
Transmission Fluid, Automatic
. . . . . . . . . . . . , . . . . . . . 6- 15
Transmitters, Keyless Entry . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Transportation, Courtesy
. . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Trip, Before Leaving . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-33 Trip Odometer
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-61
TTYUsers
..................................... 8-4
Turn Signal and Lane Change Signals . . . . . . . . . . . . . . . 2-31
Turn Signals When Towing a Trailer
. . . . . . . . . . . . . . . . 4-49
Underbody Flushing
. . . . . . . . . . . . . . . . . . . . . . . . . . . 7-42
Underbody Maintenance
......................... 6-52
Universal Transmitter
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-53
Accessories
.....................................
Erasing Channels . . . . . . . . . . . . . . . . . . . . . , . . . . . . . 2-57
Operation
. . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . , . . . 2-55
Programming
................................2-54
Rolling Code Openers . . . . . . . . . . . . . . . . . . . . . . . . . 2-56
Used Replacement Wheels
. . . . . . . . . . . . . . . . . . . . . . . . 6-44
Vehicle Control
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Vehicle Damage Warnings
. . . . . . . . . . . . . . . . . . . . . . . . . . iv
Vehicle Dimensions
. . . . , . . . . . . . . . . . . . . . . . . . . . . . . 6-62
Vehicle Identification Number
. . . . . . . . . . . . . . . . . . . . . 6-54
Vehicle Loading
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-40
Vehiclestorage
....................................
Ventilation System . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Visors, Sun
. . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-50
Voltmeter
........,............................2-64
warning Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Warning Lights, Gages and Indicators
. . . . . . . . . . . . . . . 2-62
Washer Fluid, Windshield
. . . . . . . . . . . . . . . . . . . . , . . . 6-26
Washing Your Vehicle
. . . . . . . , . . . . . . . . . . . . . . . . , . . 6-5 1
9-10
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