Page 161 of 398

Transmission Temperature Gage
If you have an automatic
transmission and this
gage, it is located above
the switchbank in the
center of the instrument
panel.
When your ignition is on, the gage shows the
temperature of the transmission oil. A reading in the
warning zone, the red area beginning at 300°F (150°C),
means you must stop driving and check into the
cause. One possible cause is a low oil level in the
transmission.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the transmission.
This could lead to costly repairs that would not
be covered by your warranty. Do not drive your
vehicle while the transmission temperature gage
reading is above normal. See your dealer for service.
Exhaust Brake Indicator Light
If your vehicle is equipped
with an exhaust brake, you
will have this light,
located above the climate
controls in the center
of the instrument panel.
The exhaust brake indicator light will come on and stay
on whenever the diesel engine exhaust brake or
exhaust restrictor is active. For more information, see
Diesel Engine Exhaust Brake on page 2-27andExhaust
Restrictor (Engine Warm-Up) on page 2-22.
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Differential Lock Indicator Light
If your vehicle has this
feature, this light is located
in the center of the
instrument panel. The light
is on when the rear
differential lock system is
in use.
The light will come on momentarily during starting. If the
light fails to come on, have it repaired as soon as
possible so you will be aware when the lock system is
in use.
SeeRear Axle Differential Lock Control on page 4-11
for more information.
Reduced Engine Power Light
If the check engine and
reduced engine power
lights are on, the electronic
throttle control may be
disabled, and a noticeable
change in the vehicle’s
performance may occur.
If the reduced engine power light is on, but there is no
change in performance, proceed to your destination.
The performance may be reduced the next time
the vehicle is driven. The vehicle may be driven at a
slower speed while the reduced engine power light is on,
but acceleration and speed may be limited.
Anytime the check engine light stays on, the vehicle
should be taken to an authorized GM dealer as soon as
possible for service.
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Highbeam On Light
This light will come on
when the high-beam
headlamps are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8.
Daytime Running Lamps (DRL)
Indicator Light
This light is located on the
instrument panel cluster. It
goes on whenever the
Daytime Running Lamps
are on.
SeeDaytime Running Lamps (DRL) on page 3-15for
more information.
When it begins to get dark, the DRL indicator light is a
reminder to turn on your headlamps.
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Low Washer Fluid Warning Light
This light will come on
when your vehicle is low
on windshield washer fluid.
For more information, seeWindshield Washer Fluid on
page 5-48.
Check Gages Warning Light
This light will come on as
you’re starting the engine,
just as a check.
If this light comes on and stays on while you are driving.
It means that either your engine coolant temperature
gage or your engine oil pressure gage may be showing
a reading in the warning zone.
When the check gages light comes on, you will also
hear a warning tone. The tone and the light will
stay activated until the problem is corrected.
This light may also come on if your vehicle is equipped
with the optional automatic engine shutdown system
and engine shutdown has begun. SeeEngine Alarm and
Automatic ShutdownunderStarting the Diesel Engine
on page 2-15.
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Fuel Gage
Your fuel gage is located
on the right side of your
instrument panel cluster.
When the ignition is on, your fuel gage lets you know
about how much fuel you have left. When the gage first
shows empty, you’ll still have a little fuel left, but you
should get more fuel soon.
If your vehicle has dual fuel tanks, the reading on the
gage is the total fuel left in both tanks.Here are four concerns of some operators. None of
these shows a problem with your fuel gage:•The gage moves a little when you turn a corner or
speed up.
•The gage does not go back to empty when you turn
off the ignition.
•At the gas station, the pump shuts off before the
gage reads full.
•It takes a little more or less fuel to fill up than the
gage indicated.
If you have a Caterpillar
®diesel engine, also see your
Caterpillar®Operation & Maintenance Manual.
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Water in Fuel Warning Light
If your vehicle has the 6.6L
or 7.8L DURAMAX®diesel
engine, this light will
come on to warn you that
there is water in the
fuel system.
For more information on how this light works, seeWater
in Fuel on page 5-10.
Air Filter Restriction Indicator
If your vehicle has this
feature, the gage is
located above the
switchbank in the center of
the instrument panel. It
monitors the engine
air filter.
As the filter gets dirty, the yellow indicator will begin to
rise. When it reaches 25 inches of vacuum on the
scale, the filter should be replaced.
After replacing the filter, reset the gage by pressing in
the yellow reset button at the bottom of the gage.
If you have a Caterpillar
®diesel engine, also see your
Caterpillar®Operation & Maintenance Manual.
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Page 167 of 398

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.
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Audio System(s)
If your vehicle came without a radio, the wiring
provisions for a radio and an antenna were installed at
the assembly plant, so that if you want, a radio can
be installed at the dealer.
Determine which radio your vehicle has and then read
the pages following to familiarize yourself with its
features.
Driving without distraction is a necessity for a safer
driving experience. SeeDefensive Driving on page 4-2.
By taking a few moments to read this manual and
get familiar with your vehicle’s audio system, you can
use it with less effort, as well as take advantage of
its features. While your vehicle is parked, set up your
audio system by presetting your favorite radio stations,
setting the tone and adjusting the speakers. Then,
when driving conditions permit, you can tune to your
favorite stations using the presets and steering
wheel controls if the vehicle has them.{CAUTION:
This system provides you with a far greater
access to audio stations and song listings.
Giving extended attention to entertainment
tasks while driving can cause a crash and you
or others can be injured or killed. Always keep
your eyes on the road and your mind on the
drive — avoid engaging in extended searching
while driving.
Keeping your mind on the drive is important for safe
driving. For more information, seeDefensive Driving on
page 4-2.
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