1998 GMC ENVOY headlamp

Interior Lamps
Brightness Control
Rotate the thumbwheel next to the headlamp switch up
to make your instrument panel lights brighter. Turn the
switch all the way up to turn
on the interior lamps.
Front Reading Lamp?
Press the button near each lamp on the overhead console
to turn the reading lamps
on and off. The lamps can be
swiveled to point in the desired direction.
If you have the
mini console, press the lens on each
lamp
to turn it on or off.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove
the key from the ignition. These lights will
stay
on for a short period of time and then will go out.
Illuminated Entry
Your vehicle is equipped with an illuminated entry feature.
When the doors are opened, the dome lamps will come
on if the DOME OVERRIDE button is out. When all the
doors are closed, or the front door handles are lifted and
released, the lamps will stay
on for a short period of
time and will then go
out. If the dome lamp button is
pressed in, the lamps will
go out immediately.
Dome Lamps
The dome lamps will come on when you open the doors.
You can
also turn the dome lamps on by rotating the
thumbwheel, located next to the parking/headlamps
knob, all the way
LIP. In this position, the dome lamps
will remain on whether the doors are opened or closed.
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You can use the DOME OVERRIDE button, located Mirrors
below the parking/headlamp knob, to set the dome
lamps to come
on automatically when the doors are Electrochromic Daymight Inside Rearview
opened, or to remain off. To turn the lamps off, press the Mirror
button once into the “in” position. With the button in
this position, the dome lamps will remain off when the
doors are open.
To return the lamps to automatic
operation, press the button again and return it to the
“out” position. With the button in this position, the dome
lamps will come on when you open the door. This will
not override the illuminated entry feature.
Battery Run-Down Protection
This feature shuts off the dome, courtesy, vanity,
reading, glove
box and underhood lamps if they are left
on for more than
20 minutes when the ignition is off.
This will keep your battery from running down.
If the battery run-down protection shuts off the interior
lamps, it may be necessary to do one of the following to
return
to normal operation:
0 Shut off all lamps and close all doors, or
Turn the ignition key to RUN.
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 vehicle will also
return to its clear daytime state when the vehicle is put
into
REVERSE (R).
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Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
Use a low gear and get a firm grip on the
steering wheel.
Get a smooth start up the hill and try to maintain
your speed. Don’t use more power than you need,
because you don’t want your wheels to start spinning
or sliding.
0 Try to drive straight up the hill if at all possible. If
the path twists and turns, you might want to find
another route.
Ease up on your speed as you approach the top of
0 Attach a flag to the vehicle to make you more visible
0 Sound the horn as you approach the top of the hill to
0 Use your headlamps even during the day. They make
the
hill.
to approaching traffic on trails or hills.
let opposing traffic know you’re there.
you more visible to oncoming traffic.
Turning or driving across steep hills can be
dangerous. You could lose traction, slide
sideways, and possibly roll over. You could be
seriously injured or killed. When driving up hills,
always try to go straight up.
A CAUTION:
Driving to the top (crest) of a hill at full speed can
cause an accident. There could be
a drop-off,
embankment, cliff, or even another vehicle. You
could be seriously injured or killed.
As you near
the top
of a hill, slow down and stay alert.
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Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule for
additional information.
Drivin at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be
impaired
-- by alcohol or drugs, with night vision
problems. or by fatigue. Here
are some tips on night driving.
0 Drive defensively.
0 Don't drink and drive.
0 Adjust your inside rearview mirror to reduce the
0 Since you can't see as well, you may need to slow
c2 "lare from headlamps behind you.
down and keep more space between
you and
other vehicles.
0 Slow down, especially on higher speed roads. Your
headlamps can light up only
so much road ahead.
In remote areas, watch for animals.
If you're tired. pull off the road in a safe place
and rest.
Night Vision
No one can see as well at night as in the daytime. But as
we get older these differences increase.
A 50-year-old
driver may require at least twice as much light to
see the
same thing
at night as a 20-year-old.
What you do
in the daytime can also affect your night
vision. For example,
if you spend the day in bright
sunshine
you are wise to wear sunglasses. Your eyes will
have
less trouble adjusting to night. But if you're
driving,
don't wear sunglasses at night. They may cut
down on glare from headlamps, but they also make a lot
of things invisible.
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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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Snow can trap exhaust gases under your vehicle.
This can cause
deadly CO (carbon monoxide) gas
to get inside. CO could overcome
you and kill
you. You can’t see it
or smell it, so you might not
know it
is in your vehicle. Clear away snow from
around the base
of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn’t collect there.
Open a window just
a little on the side of the
vehicle that’s away from the wind. This will help
keep
CO out.
Run your engine only as long as you must. This saves
fuel. When you
run the engine. make it go a little faster
than just idle. That is. push the accelerator slightly. This
uses less fuel for the heat that you get and
it keeps the
battery charged.
YOLI will need a well-charged battery to
restart the vehicle, and possibly for signaling later
on
with your headlamps. Let the heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold.
But do it as little as possible. Preserve the
fuel
as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or
so until help comes.
Recreational Vehicle Towing
Vehicles with the electronic shift transfer case require
special modifications before they can be towed
in this
manner. Please contact your dealer
.for the towing
information that is appropriate
for yoc~r
particular vehicle.
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2. Remove the black retainer clips by lifting up.
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
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5. Turn the bulb assembly to the left to remove it.
6. Put the new bulb assembly into the headlamp
assembly and turn it to the right until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp lens assembly back into the
vehicle. Install the two retaining clips.
Front Turn Signal Lamp Assembly
1. Remove the headlamp assembly as shown under
“Composite Headlamp System” earlier
in this section.
2. Twist the bulb socket to remove it from the
3. Pull the bulb straight out to remove it from the socket.
4. Push the new bulb into the socket until it snaps
5. Put the bulb socket into the lamp assembly and twist
headlamp
assembly.
into place.
it to the right until it is tight.
6. Put the headlamp assembly back into the vehicle.
Install the two retaining clips.
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