Service Transmission Warning Light
If your vehicle has an Allison automatic transmission,
certain transmission malfunctions will turn this light on.
This light is located with
the auxiliary warning lights
in the center of the
instrument panel.
If this light comes on while you are driving, do not use
the transmission shift control or you may lose 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 you continue driving your vehicle after
the transmission warning light comes on, you could
damage the transmission. While this light is on,
the transmission cannot operate in all gears. If you
attempt to shift gears, the vehicle may not
continue to move. Do not attempt to shift gears
while the transmission warning light is on. Instead,
drive directly to a GM dealer for service. If you
cannot drive to a dealer immediately, have the
vehicle towed.
Range Inhibit Warning Indicator
If your vehicle has an Allison
1000/2000/2200/2400/2500 series automatic
transmission, a lighted bar under the current gear
selected will flash.
If your vehicle has an Allison 3000/3500 series automatic
transmission, the current gear selected on the pushbutton
display will flash.
The flashing bar or gear selection indicates that
transmission range shifts may not occur.
For detailed information on shift inhibit limitations, see
the Allison Automatic Transmission Operator’s Manual in
your vehicle for further information.
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 brake systems have two brake
system warning lights on the instrument panel.
If the BRAKE system
warning light comes on, it
means that the fluid
level in the master cylinder
reservoir is low or there
is another problem
with your hydraulic brakes.
When it comes on, you will also hear a warning tone.
The BRAKE system 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 “Hydraulic
Brake Systems” underBraking on page 4-5.If the service brakes soon
warning light comes on, it
means there may be
something wrong in the
brake system.
When this light comes on, you will also hear a warning
tone. Have the system repaired immediately.
Both of these lights should come on briefly every time
you start your 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 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 BRAKE light is still on, have the vehicle towed for
service. SeeTowing Your Vehicle on page 4-35. See
“Hydraulic Brake Systems” underBraking on page 4-5
for further information.
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Anti-Lock Brake System
Warning Light
This light should come on
briefly when you start the
engine, if it does not
have your vehicle fixed
immediately.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. If the BRAKE or LOW
AIR warning light isn’t on, you still have brakes, but you
don’t have the anti-lock brake feature. If the BRAKE
and/or LOW AIR warning light is on, you don’t
have anti-lock brakes and there’s a problem with your
regular brakes. SeeBrake System Warning Light
on page 3-31.
Trailer Anti-Lock Brake System
Warning Light
If your vehicle is connected
to a trailer with anti-lock
brakes, this light should
come on briefly, as a
check, when you turn on
the ignition.
When this light comes on and stays on, it means there
is something wrong in the trailer anti-lock brake
system. Have the system repaired immediately.
If an anti-lock brake system equipped trailer is not
connected, this light is not functional.
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Air Pressure Gage
If your vehicle has air
brakes, the air pressure
gage is located above the
switchbank in the center
of the instrument panel.
This gage shows the air pressure for both your front
and rear brake systems.
If the needle on the gage indicates that the air pressure
is below 60 to 75 psi (415 to 517 kPa), the low air
warning light will come on. An alarm will also sound if
this happens.
The top pointer shows the pressure available for the
front system, while the bottom pointer shows pressure
for the rear. There should be no more than 4 psi
(28 kPa) difference showing between the systems.
Don’t drive until both pointers are showing at least
120 psi (827 kPa), so you’ll have enough air if you need
to apply your brakes.
Hourmeter Gage
To access the engine hourmeter gage, press the trip
odometer button three times.
The instrument panel cluster displays the accumulated
engine run time hours using the reconfigurable
odometer display. The engine run time hours displays
only when the ignition is in the LOCK or ACCESSORY
position and the trip reset button is pressed for about
four seconds. The value of the accumulated hours does
not change when the battery is disconnected.
The hourmeter resets to 0.0 when 10,000 hours are
accumulated. The instrument panel cluster begins to
reaccumulate the engine run time hours from 0.0 hours.
Audio System(s)
Notice:Before adding any sound equipment to
your vehicle, such as an audio system, CD player,
CB radio, mobile telephone, or two-way radio, make
sure that it can be added by checking with your
dealer. Also, check federal rules covering mobile
radio and telephone units. If sound equipment can
be added, it is very important to do it properly.
Added sound equipment may interfere with
the operation of your vehicle’s engine, radio, or
other systems, and even damage them. Your
vehicle’s systems may interfere with the operation
of sound equipment that has been added.
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