1998 GMC ENVOY parking brake

Rotate the knob to the right to the master lamps symbol
to turn on all the lamps listed as well as
the headlamps.
Rotate the
knob all the way to the left to turn off your
lamps and put the system in automatic headlamp mode.
Automatic Headlamp System
When it is dark enough outside, your automatic
headlamp system will turn on your headlamps at the
normal brightness along with other lamps such as the
taillamps, sidemarker, parking lamps and the instrument
panel lights. The radio lights will also be dim.
Your vehicle is equipped with High Intensity Discharge
(€€ID) headlamps. Your headlamps come on at lower
intensity and gradually increase to full brightness.
Your vehicle is equipped with
a light sensor on the top
of the instrument panel under the radio speaker grille,
so
be sure it is not covered, which will cause the system to
be on whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather, a tunnel or fueling your vehicle in a low-light
area. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running Lamps
(DRL) and the automatic headlamp systems
so that driving under bridges or bright overhead street lights
does not affect the system. The DRL and automatic
headlamp system will only be affected when the light
sensor
sees a change in lighting lasting longer than
the delay.
To idle your vehicle with the automatic headlamp
system
off, set the parking brake while the ignition is
off. Then start your vehicle. The automatic headlamp
system will stay off until you release the parking brake.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
Lamps On Reminder
A reminder chime will sound when your headlamps or
parking lamps
are manually turned on and your ignition
is in
OFF, LOCK or ACCESSORY. To disable the
chime, rotate the thumb wheel all the way down. In
the
automatic mode, the headlamps turn off once the
ignition key is in
OFF,
Daytime Running Lamps
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short periods after dawn and before sunset.
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The DRL system will make your high-beam headlamps
come
on at reduced brightness when:
Fog Lamps
the ignition is on,
the headlamp switch is in automatic headlamp
mode and
the parking brake is released.
When the DRL are on, only your high-beam headlamps
will be on. The taillamps, sidemarker and other lamps
won’t be on. The instrument panel won’t be lit up either.
When it begins to get dark, the high-beam headlamps
will automatically switch from DRL to the regular
low-beam headlamps.
When you turn
the headlamp switch off, the regular
low-beam headlamps will
go off, and your high-beam
headlamps will change to the reduced brightness
of DRL
provided it is not dark outside.
To idle your vehicle with
the DRL off, set the parking
brake. The DRL will stay off until
you release the
parking brake.
As with any vehicle, you should turn on the regular
headlamp system
when you need it. Use your fog lamps
for better vision in foggy or misty
conditions. Your low-beam headlamps or your parking
lamps must be on for your fog lamps to work.
The fog lamp switch is
on the instrument panel under
the lamps switch. Press
the switch to turn the fog lamps
on. Press the switch again to turn them
off. A light will
glow in
the switch when the fog lamps are on.
Remember,
fog lamps alone will not give off as much
light as your headlamps. Never use your fog lamps in
the dark without turning on your headlamps.
The
fog lamps will go off whenever your high-beam
headlamps come on. When the high beams
go off, the
fog lamps will come on again.
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Brake System Warning Light
When the ignition is on, the brake system warning light
will come on when you set your parking brake. The light
will stay on
if your parking brake doesn’t release fully.
If it stays on after your parking brake is fully released, it
means you have a brake problem.
If the light comes on while you are driving, pull off the
road and stop carefully.
You may notice that the pedal is
harder to push.
Or, the pedal may go closer to the floor.
It may take longer to stop.
If the light is still on, have the
vehicle towed for service. (See “Towing Your Vehicle”
in the Index.)
Your vehicle’s hydraulic brake system is divided into
two parts.
If one part isn’t working, the other part can
still work and stop you. For good braking, though, you
need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
This light should come
on
briefly when you turn the
ignition key to
RUN. If it
it fixed so it will be ready
to warn you if there’s
a problem.
(0) (8> doesn’t come on then, have
BRAKE
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident.
If the light is still on after you’ve
pulled off the road and stopped carefully, have
the vehicle towed for service.
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What should I do if my vehicle stalls, or is about
to stall, and
I can’t make it up the hill?
A: If this happens, there are some things you should
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do, and there are some things you must not do.
First, here’s what you
should do:
Push the brake pedal to stop the vehicle and keep
it
from rolling backwards. Also, apply the
parking brake.
If your engine is still running, shift the transmission
to REVERSE
(R), release the parking brake, and
slowly back down the
hill in REVERSE (R).
If your engine has stopped running, you’ll need to restart
it. With the brake pedal depressed and the parking brake
still applied, shift the transmission
to PARK (P) and
restart the engine. Then, shift to REVERSE
(R), release
the parking brake, and slowly back down the
hill as
straight as possible
in REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at
the 12 o’clock position. This
way. you’ll be able to tell
if your wheels are straight
and maneuver
as you back down. It’s best that you
back down the
hill with your wheels straight rather
than
in the left or right direction. Turning the wheel
too far to the left or right will increase the possibility
of
a rollover. Here
are some things you
must r7ot do if you stall, or are
about to stall, when going up
a hill.
0 Never attempt to prevent a stall by shifting into
NEUTRAL
(N) to “rev-up” the engine and regain
forward momentum. This won’t work. Your vehicle
will roll backwards very quickly and you could go
out of control.
Instead, apply the regular brake to stop
the vehicle.
Then apply the parking brake. Shift to REVERSE
(R), release the parking brake, and slowly back
straight down.
0 Never attempt to turn around if you are about to stall
when going up
a hill. If the hill is steep enough to
stall your vehicle, it’s steep enough to cause you to
roll over if you turn around. If you can’t make it up
the
hill, you must back straight down the hill.
Q: Suppose, after stalling, I try to back down the
hill and decide
I just can’t do it. What should
I do?
A: Set the parking brake, put your transmission in
PARK (P) and turn off the engine. Leave the
vehicle and go get some help. Exit on the uphill
side and stay clear of the path the vehicle would
take
if it rolled downhill.
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Q.' Am I likely to stall when going downhill?
A: It's much nm-e likely to happen going uphill. But if
it happens going downhill, here's what to do.
0 Stop your vehicle by applying the regular brakes.
Shift to PARK (P) and. while still braking. restart
Apply the parking
brake.
the engine.
Shift back to a low gear, release the parking brake,
and drive straight d6wn.
0 If the engine won't start, get out and get
Driving Across an Incline
Sooner or later, an off-road trail will probab lelp. y go
across
the incline
of a hill. If this happens, you have to decide
whether to
try to dri\:e across the incline. Here are some
things to consider:
0 A hill that can be driven straight up or down may be
too steep to drive across. When you
go straight up or
down a
hill, the length of the wheel base (the
distance from the front wheels
to the rear wheels)
reduces the likelihood the vehicle
will tumble end
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over end. But when you drive across an incline, the
much more narrow track width
(the distance between
the left and right wheels) may not prevent the vehicle
from tilting and rolling over.
Also. driving across an
incline puts more weight on the downhill wheels.
This could cause a downhill slide
or a rollover.
Surface conditions can be
a problem when you drive
across
a hill. Loose gravel, muddy spots, or even wet
If the vehicle slips sideways, it can hit something
that
will trip it (a rock, a rut, etc.) and roll over.
Hidden obstacles can make the steepness
of the
incline even worse.
If you drive across a rock with
the
uphill wheels. or if the downhill wheels drop into
a rut or depression, your vehicle can tilt even n1oI-e.
e orass can cause your tires to slip sideways. downhill.
For reasons like these.
you need to decide carefully
whether to
try to drive across an incline. Just because
the trail goes across the incline doesn't mean you have
to drive it. The last vehicle to try it might have
rolled over.
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Driving On Grades
Reduce speed and shift to a 1owe.r gear Iwfow you start
down a long or steep downgrade.
If you don’t shift
down. you might have to use your brakes
so much that
they would get hot and no longer work well.
On
a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating.
You should use DRIVE
(D) when towing a trailer.
Operating your vehicle
in DRIVE (D) when towing a
trailer
will minimize heat buildup and extend the life of
your transmission.
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a lower
temperature than at normal altitudes.
If you twn your
engine off imnlediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar to
engine overheating.
To avoid this, let the engine run while
parked (preferably on level ground)
with the automatic
transmission
in PARK (PI for a few minutes before turning
the engine off.
If you do get the overheat warning. see
”Engine Overheating”
in the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached.
on a hill. If‘ something goes wrong, your rig
could start
to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here‘s
how
to do it:
1.
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3.
4.
5.
Apply your regular brakes, but don’t shift into
PARK
(P) yet. Then turn your wheels into the curb
if facing downhill or into traffic if facing uphill.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes
until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking
brake, and then shift into PARK
(P).
Release the regular brakes.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
0 Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s
a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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Trailer Wiring Harness
The heavy-duty trailer wiring is an eight-wire harness
assembly. The harness is stored under the vehicle, on the
driver’s side corner frame rear crossmember. The
heavy-duty trailer wiring has a 30-amp feed wire
with
an in-line fuse located by the junct.ion block. See “Fuses
and Circuit Breakers”
in the Index. The harness does not
have a cannector and should be wired by
a qualified
electrical technician. The technician can use the
following color code chart when connecting the wiring
harness
to your trailer.
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Dark Blue: Use for electric trailer brakes or
auxiliary wiring.
Red: Use for battery charging;
it connects to the
starter solenoid.
Light Green: Back-up lamps.
Brown: Taillamps and parking lamps.
Yellow: Left stoplamp and turn signal.
Dark Green: Right stoplamp
and turn signal.
White (Heavy Gage): Ground wire.
White (Light Gage): Auxiliary stoplamp.
Securely attach the harness to the trailer, then tape or
strap
it to your vehicle’s frame rail. Be sure you leave it
loose enough so the wiring doesn’t bend or break, but
not
so loose that it drags on the ground. Store the
harness
in its original place. Wrap the harness together
and tie
it neatly so it won’t be damaged.
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