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Low Coolant Warning Light
You have a low coolant
warning light. If this light
comes on, your system is
low on coolant and the
engine may overheat.
The warning light should come on briefly, as a check,
when you turn on the ignition.
When it comes on, you will also hear a warning tone at
several beats per second for 10 seconds. SeeEngine
Coolant (Gas and DURAMAX™ engines) on page 5-32
orEngine Coolant (Caterpillar
®Diesel Engines) on
page 5-35and have your vehicle serviced as soon as
you can.
This light may also come on if your vehicle is equipped
with the automatic engine shutdown system and
engine shutdown has begun. SeeEngine Alarm and
Automatic ShutdownunderStarting Your Diesel Engine
on page 2-14.
Wait to Start Indicator
If your vehicle has the DURAMAX™ 6600, you will have
glow plugs. If your vehicle has the DURAMAX™ 7800,
you will have glow plugs and an inlet heater. If your
vehicle has a Caterpillar
®engine, you will have an inlet
heater.
The light in the center of
the instrument panel will
come on when the
inlet heater is on and the
ignition key is in RUN.
Wait until the indicator light turns off before turning the
ignition key to START.
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Malfunction Indicator Lamp
Service Engine Soon Light
If this light comes on or
flashes while you are
driving, two things may
happen.
First, you will not notice any difference in engine
performance, but your tail pipe emissions may increase.
Second, your engine may not run properly or may
stall without warning. If either of these things happen,
drive or tow your vehicle to your dealer for service.
This light should come on when the ignition is on, but
the engine is not running, as a check to show you
it is working. If it does not come on at all, have
it repaired.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Oil Pressure Gage
The engine oil pressure gage, on the lower right portion
of your instrument panel cluster, shows engine oil
pressure in psi (pounds per square inch) or in kPa
(kilopascals). Oil pressure may vary with outside
temperature and oil viscosity, but readings of
30 to 40 psi (205 to 275 kPa) on gasoline engines at
operating temperature and moderate road speeds
are normal. If you have a diesel engine, the normal
operating range should be between 35 and 70 psi
(240 to 480 kPa).
United StatesCanada
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Transmission Temperature Gage
If you have an automatic
transmission, this gage 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 comfort
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 2-25.
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 inter-axle
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.
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Reduced Engine Power Light
If the check engine and
reduced engine power
lights are on, the throttle
may be disabled, and
a noticeable reduction in
the vehicle’s performance
may occur.
If the reduced engine power light is on, but there is no
reduction 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
reduced speed while the reduced engine power light is
on, but acceleration and speed may be reduced.
Anytime the check engine light stays on, the vehicle
should be taken to an authorized GM dealer as soon as
possible for service.
Daytime Running Lamps
Indicator Light
This light is located on the
instrument panel cluster. It
goes on whenever the
Daytime Running Lamps
are on.
SeeDaytime Running LampsunderExterior Lamps on
page 3-13for further 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 5-44.
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 Your Diesel
Engine on page 2-14.
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.
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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.
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 yellow pointer shows the pressure available for the
front system, while the green 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
115 psi (793 kPa), so you’ll have enough air if you need
to apply your brakes.
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Hourmeter Gage
The instrument panel cluster displays the accumulated
engine run time hours using the reconfigurable
odometer VF display. The engine run time hours
displays only when the ignition is in the OFF or ACC
position and the trip reset switch is pressed for
about four seconds.
When the ignition is in the OFF or ACC position, the
instrument panel cluster displays the engine
accumulated hours for up to 30 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 you add any sound equipment to
your vehicle – like a tape player, CB radio, mobile
telephone or two-way radio – be sure you can
add what you want. If you can, it’s 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
improperly.
So, before adding sound equipment, check with
your dealer and be sure to check federal rules
covering mobile radio and telephone units.
Your audio system has been designed to operate easily
and to give years of listening pleasure. You will get
the most enjoyment out of it if you acquaint yourself with
it first. Figure out which radio you have in your vehicle,
find out what your audio system can do, and how to
operate all of its controls to be sure you are getting
the most out of the advanced engineering that went
into it.
Setting the Time
Press and hold the HR or MIN arrow for two seconds.
Then press the HR (down) arrow until the correct
hour appears on the display. Press and hold the
MIN (up) arrow until the correct minute appears on
the display. The time may be set with the ignition on
or off.
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Inter-Axle Differential Lock Control
If you vehicle has this
feature, the switch is
located in the center 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 press the bottom of this switch. It locks your
rear differentials so that power is transmitted equally to
both rear axles.
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 center of the instrument
panel will light.
Notice:Turning on the inter-axle differential lock
while the rear wheels are spinning freely, as
they might on snow or ice, can damage the axle(s).
Turn on this control only while the wheels are
not spinning freely.
Rear Axle Differential Lock Control
If your vehicle has a
controlled traction or
locking differential axle, the
switch is located in the
center 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 press the bottom of this switch. It locks your rear
differential so that power is transmitted equally to
both rear wheels.
Let up on the accelerator before you turn on your rear
axle differential lock.
Notice:Turning on the inter-axle differential lock
while the rear wheels are spinning freely, as
they might on snow or ice, can damage the axle(s).
Turn on this control only while the wheels are
not spinning freely.
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