1999 GMC ENVOY lights

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2-44
Mirrors
Electrochromic Day/Night Inside
Rearview Mirror
This mirror automatically changes to reduce glare from
headlamps behind you. A photocell on the back of the
mirror senses when it is becoming dark outside. Another
photocell built into the mirror surface senses when
headlamps are behind you.
At night, when the glare is too high, the mirror will
gradually darken to reduce glare (this change may take a
few seconds). The mirror will return to its clear daytime
state when the glare is reduced. The mirror will also
return to its clear daytime state when the vehicle is put
into REVERSE (R).
Press the AUTO button at the base of the mirror to turn
on the automatic feature. The button has an indicator
light to show it is on. Press the OFF button to turn the
automatic feature off.
Time Delay
The automatic mirror has a time delay feature which
prevents unnecessary switching from the night back to
the day position. This delay prevents rapid changing of
the mirror as you drive under lights and through traffic.
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2-66
Warning Lights, Gages and Indicators
This part describes the warning lights and gages that may be
on your vehicle. The pictures will help you locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages and
warning lights work together to let you know when
there's a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for about eight seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for about 20 seconds, then it
will flash for about
55 seconds.
If the driver's belt is already buckled, neither the chime
nor the light will come on.
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3-3
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 not
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
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, theblower speed will decrease. To maintain interior comfort,
the airflow will adjust between the instrument panel air
outlets and floor outlets. On bright sunny days in cool
weather, the airflow may come out of the air conditioning
and floor outlets (bi
-level mode) to maintain comfort and
prevent stuffiness.
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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4-18 Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain and its
many different features. Here are some things to consider.
Surface 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.
Surface Obstacles. 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:

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
surface 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 ªDrunken Drivingº in the Index.
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4-28
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 headlamps.
Keep your windshield and all the glass on your 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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6-21
Radiator Pressure Cap
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure
-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the cap
line up with the overflow tube on the radiator
filler neck.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches a preset temperature.
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 265F (129C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.
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6-56
Fuse/Circuit
BreakerUsage
A Not Used
B Not Used
1 Not Used
2 Cigarette Lighter, Data
Link ConnectorFuse/Circuit
BreakerUsage
3 Cruise Control Module and Switch,
Body Control Module, Heated Seats
4 Gages, Body Control Module,
Instrument Panel Cluster
5 Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
6 Steering Wheel Audio Control
Illumination
7 Headlamp Switch, Body Control
Module, Headlamp Relay
8 Courtesy Lamps, Battery Run
-Down
Protection
9 Not Used
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior Lights
13 Auxiliary Power
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9-6
Lights
Air Bag Readiness 1-22, 2-67 . . . . . . . . . . . . . . . . . . . . . . .
Anti-Lock Brake System Warning 2-69, 4-7 . . . . . . . . . . . .
Brake System Warning 2-68 . . . . . . . . . . . . . . . . . . . . . . . . .
Charging System 2-67 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Gages 2-75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gate Ajar 2-75 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Low Fuel 2-76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Safety Belt Reminder 1-8, 2-66 . . . . . . . . . . . . . . . . . . . . . .
Security Warning 2-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service 4WD 2-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Engine Soon 2-70 . . . . . . . . . . . . . . . . . . . . . . . . . .
Loading Your Vehicle 4-41 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Loading Your Vehicle for Off-Road Driving 4-15 . . . . . . . . . .
Locking Rear Axle 2-32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lockout Prevention 2-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lockout Switch 2-32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Low Fuel Light 2-76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lubricants and Fluids 7-45 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lubrication Service, Body 7-40 . . . . . . . . . . . . . . . . . . . . . . . .
Luggage Carrier 2-53 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lumbar Controls 1-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance Record 7-47 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance Schedule 7-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long Trip/Highway 7-6, 7-27 . . . . . . . . . . . . . . . . . . . . . . . Owner Checks and Services 7
-39 . . . . . . . . . . . . . . . . . . . . .
Periodic Maintenance Inspections 7-43 . . . . . . . . . . . . . . . .
Recommended Fluids and Lubricants 7-45 . . . . . . . . . . . . .
Scheduled Maintenance Services 7-4 . . . . . . . . . . . . . . . . . .
Short Trip/City 7-5, 7-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance, Underbody 6-52 . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance When Trailer Towing 4-54 . . . . . . . . . . . . . . . . .
Malfunction Indicator Lamp 2-70 . . . . . . . . . . . . . . . . . . . . . .
Memory Seat 1-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Methanol 6-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mirrors 2-44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Convex Outside 2-45 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrochromic Day/Night Inside Rearview 2-44 . . . . . . . .
Heated Outside Rearview 2-45 . . . . . . . . . . . . . . . . . . . . . . .
Illuminated Visor Vanity 2-55 . . . . . . . . . . . . . . . . . . . . . . .
Outside 2-45 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Folding 2-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Model Reference iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mountain Roads 4
-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Multifunction Lever 2-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Net, Convenience 2-51 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neutral 2-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
New Vehicle ªBreak-Inº 2-13 . . . . . . . . . . . . . . . . . . . . . . . . .
Night Vision 4-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Normal Maintenance Replacement Parts 6-61 . . . . . . . . . . . . .
Odometer 2-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Off-Road Driving with Your Four-Wheel-Drive
Vehicle 4-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Off-Road Recovery 4-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil, Engine 6-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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