1999 GMC C-SERIES display

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3-3 Optional Comfort Controls (If Equipped)
If your vehicle has air conditioning, your comfort
controls will look like this.
Your system has a lighted display showing each system
when it is operating. During normal operation, all the
lights won't come on at the same time. Only the ones
displaying the current settings will light.
Temperature Selector Bar
The bar under your system display lets you select the
temperature of the air coming into the passenger area of
your vehicle. Press COLD for cooler air and press HOT
for warmer air. Release the bar when the system reaches
the temperature you want. The temperature is shown on
the display by an arrow moving between C and H.
If your engine is equipped with an engine coolant heater,
you can use it during initial start
-up in cold weather
(20
F (
-8
C) or lower) to help heat the passenger
compartment faster. See ªEngine Coolant Heaterº in
the Index.
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3-4
Left Blend Button
The airflow can be blended between the two positions.
To blend between the positions, press the side of the
button showing the area where you would like more
airflow. The system will automatically begin to blend
toward the position chosen. To stop the system between
positions, just press the same side of the button again.
VENT: Press the top of the button and all of the
airflow will come through the instrument panel vents.
HEATER: Press the bottom of this button and all
of the airflow will come through the floor outlet.
Right Blend Button
The airflow can be blended between the two positions.
To blend between positions, press the side of the button
showing the area where you would like more airflow.
The system will automatically begin to blend toward the
position chosen. To stop the system between positions,
just press the same side of the button again.
DEFOG: This setting operates the defogger. Air
comes out near the bottom of the windshield and at your
front side windows.
HEATER: Press the bottom of this button and
heated air comes out near the floor.A/C Button
Press the A/C button to turn your air conditioner on and
off. The A/C symbol will light on your display, and air
will come out of your instrument panel vents. The fan
will automatically be set on LOW.
MAX Button
If you press the MAX button, the air in your vehicle will
be recirculated. With the air conditioner on, MAX will
give you maximum cooling. It can also be used in all
modes to help keep dust out of your vehicle. When
MAX is selected, REC will light on the display.
Fan Control Button
This button is in the upper passenger's side corner of
your system control panel. The fan has four settings:
low, medium low, medium high and high. Press the top
of the button with the plus symbol to increase airflow.
Press the bottom of the button with the minus symbol to
decrease airflow. The setting you select is shown on
your display as LOW, MED, HI or OFF.
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OFF
Press this button to turn the air conditioning/heating
system off. Pressing OFF will erase the present mode of
operation from the system's memory. Outside air will
still come out of the heater outlet whenever the vehicle
is moving forward.
If the OFF button is pressed, you must press A/C,
MAX or one of the BLEND buttons to turn the system
back on.
Air Conditioning
When you first turn on your vehicle's air conditioning,
open the windows long enough to clear the vehicle of
hot air, then close them. Using the MAX button can also
help. See ªMAX Buttonº earlier in this section for
more information.
For normal cooling on hot days, use A/C with the
temperature selector toward C.
When you press the A/C button to turn the air
conditioner off, the system will operate in the vent
mode. When you turn the air conditioner back on, the
system will operate in the mode you last selected unless
the OFF button was pressed.If your air conditioner develops high system pressure, it
will automatically go into the MAX mode and REC will
light on your display. The A/C system will remain in the
MAX mode, even if you press the MAX button, until
system pressure returns to a normal level.
Heating
On cold days, use HEATER with the temperature
selector all the way toward H. When the inside of the
vehicle has reached a comfortable temperature, maintain
it by using the temperature selector bar.
If your vehicle is equipped with a diesel engine, and the
engine has been idling for a long time when it's cold
outside, your heater may blow out cool air. This is
normal. When you increase the engine speed under load,
your heater should blow out warmer air. If it doesn't,
your coolant level may be low. See ªEngine Coolantº in
the Index to check your coolant level.
While idling your diesel engine, you can use the MAX
button to recirculate the air in the cab to help maintain
interior heat. This will preserve engine coolant temperature
and cab heat when idling cannot be avoided.
Using the MAX button while driving is not recommended
because interior window fogging can result.
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Ventilation Tips

Keep the hood and front air inlet free of ice, snow or
any other obstruction (such as leaves). The heater
and defogger will work far better, reducing the
chance of fogging the inside of your windows.

When you enter a vehicle in cold weather, turn the
blower fan to high for a few moments before driving
off. This helps clear the intake ducts of snow and
moisture and reduces the chance of fogging the
inside of your windows.

Keep the air path under the seats clear of objects.
This helps air to circulate throughout your vehicle.
The air vents are located in the center and on the sides of
your instrument panel. You can move the vents to direct
the flow of air or close the vents altogether. When you
close a vent, it will increase the flow of air coming out
of any vents that are open.
If your vehicle does not have air conditioning, there are
air vent controls located below the instrument panel.Audio Systems
Your Delco Electronics audio system has been designed
to operate easily and give years of listening pleasure.
You will get the most enjoyment out of it if you acquaint
yourself with it first. Find out what your Delco
Electronics system can do and how to operate all its
controls, to be sure you're getting the most out of the
advanced engineering that went into it.
Setting the Clock
While pressing the SET button, press the UP button
until the correct hour appears on the display and the
DOWN button until the correct minute appears on the
display. If you press and hold the UP/DOWN button,
hours or minutes will advance rapidly.
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3-8 AM-FM Stereo
Playing the Radio
ON
-OFF: Press the round button to turn the radio on.
Press it again to turn the radio off.
VOLUME: Slide the VOLUME lever to the right to
increase volume or to the left to decrease volume.
CALL: Press this button to display the clock for
a few seconds when the radio is on. To change what is
normally shown on the display (station or time), press
this button and the SET button.Finding a Station
AM/FM: Press this button to switch between AM and
FM. The display shows your selection.
TUNE: Press UP to increase the frequency of a radio
station and DOWN to decrease the frequency of a radio
station. If you press and hold the UP or DOWN button
for more than half a second, the radio will tune rapidly
in that direction.
SEEK: Press SEEK to tune the radio to the next higher
station and stay there.
SCAN: Press SCAN to listen to the next higher
radio station for a few seconds. Press SCAN again
to stop scanning.
PUSHBUTTONS: The six numbered pushbuttons
let you return to your favorite stations. You can set up to
12 stations (six AM and six FM). Just:
1. Turn the radio on.
2. Press AM/FM to select a band.
3. Tune in the desired station.
4. Press SET. (SET will appear on the display and will
blink for about eight seconds.)
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5. Press one of the six pushbuttons within eight
seconds. In the display, SET will stop blinking
indicating the preset is set. Whenever you press that
numbered button, the station you set will return.
6. Repeat the steps for each pushbutton.
Also, you can use the automatic memory SET button
to set the pushbuttons. You can set up to 12 stations
(six AM and six FM). Just:
1. Press AM/FM to select a band.
2. Press and hold SET. (SET will appear on the display
and will blink.)
3. While pressing the SET button, press the SEEK
button. Release both switches. The radio will
automatically search the band and select radio
stations, up to six, which have good signal strength.Setting the Tone
BAS: Slide this lever left or right to decrease or increase
the bass.
TRE: Slide this lever left or right to decrease or
increase the treble. If a station is weak or noisy, you may
want to decrease the treble.
LOUD: To increase bass and treble at low volumes,
press this button. LOUD will appear in the display. Press
this button again to turn LOUD off.
Adjusting the Speakers
BAL: Slide this lever to the left or right to adjust
the speaker balance between the left and right speakers.
The middle position balances the sound between
the speakers.
FAD: Slide this lever to the left or right to adjust
the speaker balance between the front and rear speakers.
The middle position balances the sound between
the speakers.
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3-10 Remote Cassette Tape Player (If Equipped)
Your tape player is built to work best with tapes that are
up to 30 to 45 minutes long on each side. Tapes longer
than that are so thin they may not work well in this player.
To load a cassette tape, hold the cassette with the tape to
the right. Then, insert the cassette tape. Tape direction is
displayed by the lighted arrow. To change the tape
direction, press the FF button.
Once the tape is playing, use the control knobs for
VOLUME, BAL, FAD, BAS and TRE just as you do
for the radio.
REW: Press the left arrow to rapidly reverse the tape.
Press FF to stop reversing the tape.FF: Press the right arrow to rapidly advance the tape.
Press REW to stop forwarding the tape.
PROGRAM: An arrow will light on the display to
show which side of the tape is playing.
EJ: Press this button to remove the tape.
There is a space provided with your remote cassette tape
player to keep cassette tapes in.
Understanding Radio Reception
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise if you ever get it.
FM Stereo
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km). Tall
buildings or hills can interfere with FM signals, causing
the sound to come and go.
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6-16 Engine Oil Additives
Don't add anything to your oil. Your dealer is ready to
advise if you think something should be added.
When to Change Engine Oil
Your vehicle has a computer that lets you know when to
change your engine oil. This is not based on mileage,
but on engine revolutions and engine operating
temperature. When the computer has calculated that the
oil needs changing, the Oil Life Monitor will indicate
that a change is necessary. The mileage between oil
changes will vary depending on how you drive your
vehicle
-- usually between 3,000 miles (5 000 km) and
7,500 miles (12 500 km) since your last oil change.
Under severe conditions, the indicator may come on
before 3,000 miles (5 000 km). Never drive your vehicle
more than 7,500 miles (12 500 km) or 12 months
(whichever occurs first) without an oil change.
The system won't detect dust in the oil. So, if you
drive in a dusty area, be sure to change your oil every
3,000 miles (5 000 km) or sooner. Remember to reset
the CHANGE OIL light whenever the oil is changed.How to Reset the Oil Life Monitor
To reset the CHANGE OIL message, turn the ignition
key to RUN with the engine off. Fully press and release
the accelerator pedal three times within 10 seconds. If
the CHANGE OIL message flashes for five seconds, the
system is reset. If the message does not display for five
seconds, you will need to reset the system again.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements that may be unhealthy for your skin and could
even cause cancer? Don't let used oil stay on your skin
for very long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly throw
away clothing or rags containing used engine oil. (See
the manufacturer's warnings about the use and disposal
of oil products.)
Used oil can be a real threat to the environment. If you
change your own oil, be sure to drain all free
-flowing oil
from the filter before disposal. Don't ever dispose of oil
by putting it in the trash, pouring it on the ground, into
sewers, or into streams or bodies of water. Instead,
recycle it by taking it to a place that collects used oil. If
you have a problem properly disposing of your used oil,
ask your dealer, a service station or a local recycling
center for help.
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