instrument panel GMC C-SERIES 1999 User Guide

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Let up on the accelerator before you turn on your
inter
-axle differential lock. When you turn on this
control, the DIFF LOCK indicator on the instrument
panel will light.
NOTICE:
Activating the inter-axle differential lock when
the rear wheels are actually spinning freely, as
they might on ice or snow, can cause you to lose
control of the vehicle. It can also damage the
axles. Turn on this control only when the wheels
are not spinning freely.
Rear Axle Differential Lock Control
(If Equipped)
If your vehicle has a
Controlled Traction or
Locking Differential axle,
the control is located at the
lower right corner of the
instrument panel. You'll see
this control on single rear
axle vehicles.
If you're approaching a slippery surface where it looks
like one or even both wheels may start to slip, you can
use this control. It locks your rear differential so that
power is transmitted equally to both rear wheels.
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Let up on the accelerator before you turn on your rear
axle differential lock.
NOTICE:
Activating the rear-axle differential lock when
the rear wheels are actually spinning freely, as
they might on ice or snow, can cause you to lose
control of the vehicle. It can also damage the axle.
Turn on this control only when the wheels are not
spinning freely.
Engine Air Control (If Equipped)
If your vehicle has this control, the handle is located on
the instrument panel just to the right of the steering
wheel. The control is activated by pulling the handle out
and turning slightly in either direction to lock it.
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When the handle is pulled out, the engine air intake
supply is closed off from the front scoop and an under
hood air supply is opened. This control is intended only
for use in cold weather (32
F (0
C) or below) where
snow and ice might plug the external intake.
At temperatures above 32
F (0
C), keep the control
handle pushed in.
NOTICE:
Operating this vehicle with the engine air control
on when outside temperatures are above 32
F
(0
C), could lead to costly repairs not covered by
your warranty. It will also degrade fuel economy
and the engine will not run smoothly.
Exterior Lamps
Headlamps
The lamp switches are on the left side of your
instrument panel.
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Press the top left switch to turn on your:

Parking Lamps

Marker Lamps (unless your vehicle has the optional
marker and clearance lamps switch)

Taillamps

Instrument Panel Lights

License Plate Lamps
Push the bottom left switch to turn on the headlamps, as
well as all of the lamps just listed. Push the switch
marked with the ªOº symbol to turn off your lamps.
Move the thumbwheel to the right of the off switch
down to dim your instrument panel lights. Moving this
wheel up makes these lights brighter. Moving it all the
way up will make the interior lamp come on.
A circuit breaker protects your headlamps. If you have
an electrical overload, your headlamps will flicker on
and off. Have your headlamp wiring checked right away
if this ever happens.Headlamps On Reminder (If Equipped)
If you have this system, a tone alarm will sound when
your headlamps and/or parking lamps are turned on and
your ignition is in OFF, LOCK or ACCESSORY.
Daytime Running Lamps (If Equipped)
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.
The high and low
-beam headlamps will come on at
reduced brightness in daylight when:

The ignition is on,

The headlamp switch is off and

The parking brake is released.
When the DRL are on, only your low
-beam headlamps
will be on. The exterior lamps won't be on. Your
instrument panel won't be lit up either.
When it begins to get dark, your DRL indicator light is a
reminder to turn your headlamp switch on. The other
lamps that come on with your headlamps will also
come on.
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When you turn the headlamp switch off, the regular
lamps will go off, and your low
-beam headlamps will
change to the reduced brightness of DRL.
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.
Marker and Clearance Lamps Switch
(If Equipped)
Your vehicle will have this
switch only if it is designed
to pull a trailer. If it has this
switch, you'll find it on the
upper right side of your
instrument panel, just above
the radio.If your vehicle has no radio, the switch is just above the
storage area. Use the switch to operate your clearance
and marker lamps. The marker lamps are illuminated
when the indicator light is on.
Your headlamps switch will not operate these lamps.
You can use the switch to manually blink the marker and
clearance lamps by simply turning it on and off.
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2-47 Heated Outside Mirrors (If Equipped)
If your vehicle has heated
mirrors, you'll find this
switch on the upper right
side of your instrument
panel area, just above the
radio. Use it to operate your
mirror heaters to defrost or
defog your mirrors.
When you turn on the mirror heaters, an indicator light
in the switch will be lit to tell you the heaters are on.
Once the mirrors are clear for viewing, turn the switch
off. The mirror heaters remain on until the heater switch
or ignition switch is turned off. However, when you turn
the ignition back on, the heater switch will again be on
until turned off.
Ashtray and Cigarette Lighter
(If Equipped)
The ashtray is just below the gages on the right side of
your instrument panel. If you have a cigarette lighter, it
is inside the ashtray.
To use the lighter, press it in all the way and let go.
When it's ready, it will pop back by itself.
NOTICE:
Don't hold a cigarette lighter in with your hand
while it is heating. If you do, it won't be able to
back away from the heating element when it's
ready. That can make it overheat, damaging the
lighter and heating element.
To remove the ashtray for cleaning, pull up on the
front of it.
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Instrument Panel
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A. Left Side Window Defogger
B. Main Lamps Switch
C. Vent
D. Instrument Cluster
E. Warning Lights
F. Heated Mirror Switch (Option)
G. Exhaust Brake Switch (Option)
H. Marker/Clearance Lamps Switch (Option)
I. Audio System or Storage Area
J. VentsK. Glove Box
L. Right Side Window Defogger
M. Storage Tray/Cassette Player
N. Comfort Controls
O. Air Brake Controls (If Equipped)
P. Ashtray
Q. Air Vent Controls
R. Convenience Center Fuse Panel
S. Hourmeter (Option)
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Instrument Panel Cluster
Your instrument cluster is designed to let you know at a glance how your vehicle is running. You'll know how fast
you're going, about how much fuel is left and many other things you'll need to drive safely and economically.
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Hydraulic Brake System Warning Lights
Vehicles with hydraulic systems have two brake system
warning lights on the instrument panel.
If the PRIMARY BRAKE
warning light comes on, it
means that the fluid level in
the master cylinder
reservoir is low or there is
another problem with your
primary hydraulic brakes.
When it comes on, you will also hear a warning tone.
The PRIMARY BRAKE warning light may come on,
and the warning tone may sound, when you're turning
and braking at the same time. This is normal. See
ªHydraulic Brake Systemsº in the Index.
If the AUX BRAKE
warning light comes on, it
means that there is
something wrong in the
auxiliary brake system.
When this light comes on, you will also hear a warning tone.Both of these lights should come on briefly every time
you start the engine. If they don't come on then, have
them fixed so they will be ready to warn you if there's a
problem. If one or both of these warning lights stay on
after you start the engine, there could be a brake
problem. Have your brake system inspected right away.
If one or both of these lights come on and stay 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 either light is still on, have the vehicle towed for
service. (See ªTowing Your Vehicleº in the Index.)
See ªHydraulic Brake Systemsº in the Index for
more information.
CAUTION:
Your brake system may not be working properly
if a brake system warning light is on. Driving
with either of the brake system warning lights on
can lead to an accident. If either light is still on
after you've pulled off the road and stopped
carefully, have the vehicle towed for service.
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