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CAUTION:
Using the trailer brake hand control for parking
or for holding the vehicle on a hill may not keep
the vehicle from rolling. This can happen if
someone hits the valve by accident, or if air
pressure bleeds from the system. If the vehicle
rolls, you or others could be injured. To park the
vehicle or hold it on a hill, use the parking
brake properly.
Inter-Axle Differential Lock Control
(If Equipped)
If your vehicle has this
feature, the control is
located at the lower
right corner of the
instrument panel.
If you're approaching a slippery surface where it looks
like one or even all of the wheels may start to slip, you
can use this control. It locks your rear differentials so
that power is transmitted equally to both rear axles.
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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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Trailer Connections (If Equipped)
These connections are located at the rear of the
cab. There is an air connection and a trailer
electrical connection.
Be sure that the couplings to the trailer are
made correctly.
Air Connections
The red line is the supply
line. It provides emergency
or constant air pressure. The
blue line is the control line,
providing service air.
Electrical Connections (If Equipped)
If your vehicle has this system, it has a seven-wire cable
that will go to the trailer to supply electrical power to
the trailer's lighting system. When not in use, it is stored
in the trailer air
-hose storage bracket.
NOTICE:
Starting in 1998, the center pin (also known as
the auxiliary circuit) of the 7
-pin trailer electrical
connector will be wired to provide continuous
power for the trailer anti
-lock brake systems
when the ignition key is in ON or RUN. Care
should be taken to insure that continuous power
on this circuit will not cause damage to the trailer
electrical system.
Consult with the trailer manufacturer for the
proper operation and checking procedures for
the trailer anti
-lock brake systems.
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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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CAUTION:
If your vehicle has an electric/hydraulic parking
brake, do not drive if the charging system light is
on. If the battery drains too much, the parking
brake can suddenly come on and stop the vehicle.
This can cause severe injury to you and others.
The charging system light is
located in the center of the
instrument cluster just
above the odometer.
It should come on briefly when you turn on the ignition,
before the engine is running, as a check to show that it
is working.If it stays on, or comes on while you are driving, have it
checked right away. You could have a loose generator
drive belt or some other problem.
Driving while this light is on could drain your battery. If
you must drive a short distance with the light on, turn
off your radio and other accessories.
Sustained driving with a generator failure could result in
a lack of back
-up braking if the engine quits or the
power steering pump should fail.
Voltmeter
When your engine is
running, the voltmeter gage,
at the lower left of the
instrument cluster, shows
the charging system voltage.
Readings in either warning zone indicate a possible
problem in the electrical system.
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Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system may not be able to provide full
power at engine idle. As engine speeds are increased,
this condition should correct itself because higher
engine speeds allow the charging system to create
maximum power.
You can only drive a short time on the battery. Be sure
to shut off the radio, the fan or any unnecessary
accessories and have the system serviced.
Do Not Shift Warning Light
If your vehicle has the
Allison MD automatic
transmission, certain
transmission malfunctions
will turn this light on.If this light comes on while you are driving, do not use
the transmission shift control. Using the transmission
shift control will result in the loss of forward gears. The
computer for the transmission senses a problem and
chooses a gear to stay in so that you can drive the
vehicle in that gear. You may not be able to drive as fast
or back up when this light is on.
NOTICE:
If the DO NOT SHIFT warning light comes on
while you are driving, it is a warning that making
a transmission ªrangeº change could leave you
stranded. The vehicle may not continue to move
if you change gears with the transmission shift
control. The transmission can't operate in all
gears because something is wrong. Leave the shift
control alone and drive directly to a GM dealer
for service. If you can't go in for service
immediately, have the vehicle towed.
Brake System Warning Light
Your vehicle has either hydraulic or air brakes. Each
system has different warning lights.
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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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