light CHEVROLET SILVERADO 1999 1.G Workshop Manual

yellowblue
3-4
BLEND: Airflow is delivered through the heater
floor outlets, center floor console outlets (if equipped),
the windshield defroster outlets and the side window
defroster outlets. The air flow can be divided between
HEATER and DEFROST depending upon where the
knob is placed between the settings. The air
conditioning compressor may run to dehumidify the
air to prevent window fogging.
DEFROST: This setting directs most of the air
through the windshield defroster outlets, side window
defroster outlets and some air through the heater outlets
and center floor console outlets (if equipped). If air from
the center floor console outlets is not desired or more
defroster performance is desired, turn the vents off at the
console. When in the DEFROST mode, the air
conditioning compressor may run to dehumidify the air
to prevent window fogging.
OUTSIDE AIR: Press this button to direct the
system to use outside air.
Pressing the OUTSIDE AIR button will cancel the
RECIRCULATION button.
RECIRCULATION: Press this button to limit
the amount of fresh outside air entering your vehicle.
This is helpful when you are trying to limit odors
entering your vehicle, because the air inside the vehicle
is being recirculated. Pressing RECIRCULATION will
recirculate air continuously.
RECIRCULATION is used when the fan control is OFF
to limit odors, outside air and dust from entering your
vehicle. All button lights will go off. The last setting
selected will activate when the blower is turned back on.
Pressing the RECIRCULATION button will cancel the
OUTSIDE AIR button.
In the BLEND mode, outside air is forced to reduce
window fogging. If the RECIRCULATION button is
pressed, the LED indicator will flash three times
indicating that forced outside air is activated.
The auto recirculation feature will activate when:

the air conditioning system is activated,

the OUTSIDE AIR button is on, and

the vehicle load is high due to city traffic, extended
idling or hot weather.

yellowblue
3-5
The system will automatically switch to the recirculation
mode to lower the system load and improve interior
comfort. The OUTSIDE AIR and RECIRCULATION
button LEDs will not change. The system will return to
the OUTSIDE AIR function when the system load
is reduced.
A/C: Press this button to turn the air conditioning
on and off. The system will cool and dehumidify the air
inside the vehicle when the A/C light is on.
Air conditioning will be automatically disabled when
the outside temperature drops below a level at which air
conditioning is ineffective.
Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
The RECIRCULATION button, below the fan knob,
allows the air inside your vehicle to be recirculated. This
setting helps to maximize your air conditioner's
performance and your vehicle's fuel economy. This
setting also cools air the fastest and can be used to keep
unwanted odors and/or dust from entering the vehicle.
When using the air conditioner, turn off theRECIRCULATION button after the vehicle reaches a
comfortable interior temperature. When the right knob
on the control panel is between HEATER and
DEFROST, the recirculation feature will not function to
reduce window fogging.
The A/C button, below the mode knob, allows the air
coming into your vehicle to be cooled. This setting is
useful for normal cooling on hot days. When you use
A/C with the RECIRCULATION button pushed in, turn
off recirculation as soon as the vehicle reaches a
comfortable interior temperature.
Maximum air conditioning performance is obtained by
pressing the A/C button, the RECIRCULATION button
and turning the temperature knob fully counterclockwise
to the blue area. This setting also cools air the fastest.
After the vehicle's interior reaches a comfortable
temperature, press the OUTSIDE AIR button to place
the air conditioning system in the normal mode.
Passenger Compartment Air Filter (If Equipped)
Your vehicle may be equipped with a passenger
compartment air filter, which filters outside air entering
the vehicle. For information on replacing the filter see
ªPassenger Compartment Air Filterº in the Index.

yellowblue
3-9 AM-FM Stereo
Playing the Radio
VOLUME: This knob turns the system on and off and
controls the volume. To increase volume and turn the
radio on, turn the knob clockwise. Turn it
counterclockwise to decrease volume and turn the
radio off.
RECALL: Display the time with the ignition off by
pressing the recall knob. When the radio is playing,
press this knob to recall the station frequency.Finding a Station
AM
-FM: Press the lower knob to switch between
AM and FM. The display shows your selection.
TUNE: Turn the lower knob to tune in radio stations.
SEEK: Press the right arrow to tune to the next higher
station and the left arrow to tune to the next lower
station and stay there.
SCAN: Press both SEEK buttons to listen to a few
seconds of each radio station. SCAN will light up on the
display. Press the right arrow to tune in the next higher
station and press the left arrow to tune to the next lower
station. Press VOLUME or both SEEK buttons to
stop scanning.

yellowblue
3-14
SCV: Your system has a feature called
Speed
-Compensated Volume (SCV). With SCV, your
audio system adjusts automatically to make up for road
and wind noise as you drive. Set the volume at the
desired level. Turn the control ring behind the upper
knob clockwise to adjust the SCV. Then, as you drive,
SCV automatically increases the volume, as necessary,
to overcome noise at any particular speed. The volume
level should always sound the same to you as you drive.
If you don't want to use SCV, turn the control all the
way down. Each notch on the control ring allows for
more volume compensation at faster vehicle speeds.
Finding a Station
AM
-FM: Press this button to switch between AM, FM1
and FM2. The display will show your selection.
TUNE: Press this knob lightly so it extends. Turn it to
choose radio stations. Push the knob back into its stored
position when you're not using it.
SEEK: Press the right arrow to tune to the next higher
station and the left arrow to tune to the next lower station
and stay there. The sound will mute while seeking.SCAN: Press and hold SEEK for two seconds until
SCAN appears on the display. SCAN allows you to
listen to stations for a few seconds. The receiver will
continue to scan and momentarily stop at each station
until you press the button again. The sound will mute
while scanning.
PUSHBUTTONS: The six numbered pushbuttons let
you return to your favorite stations. You can set up to
18 stations (six AM, six FM1 and six FM2). Just:
1. Turn the radio on.
2. Press AM
-FM to select the band.
3. Tune in the desired station.
4. Press AUTO TONE to select the setting you prefer.
5. Press and hold one of the six pushbuttons. The sound
will mute. When it returns, release the button.
Whenever you press that numbered button, the
station you set will return and the tone you selected
will be automatically selected for that button.
6. Repeat the steps for each pushbutton.

yellowblue
3-15
P. SCAN: The preset scan button lets you scan through
your favorite stations stored on your pushbuttons. Select
either the AM, FM1 or FM2 mode and then press
P. SCAN. It will scan through each station stored on
your pushbuttons and stop for a few seconds before
continuing to scan through all of the pushbuttons.
Press P. SCAN again or one of the pushbuttons to stop
scanning to listen to a specific preset station. P. SCAN
will light up on the display while in this mode. If one of
the stations stored on a pushbutton is too weak for the
location you are in, the radio display will show the
channel number (P1
-P6) for several seconds before
advancing to the next preset station.
Setting the Tone
BASS: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase bass
and counterclockwise to decrease bass. When the BASS
control is rotated, the AUTO TONE display will go blank.
TREB: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase
treble and counterclockwise to decrease treble. When
the TREB control is rotated, the AUTO TONE display
will go blank. If a station is weak or noisy, you may
want to decrease the treble.
Push these knobs back into their stored positions when
you're not using them.AUTO TONE: Press this button to select among the six
preset equalization settings and tailor the sound to the
music or voice being heard. Each time you press the
button, the selection will switch to one of the preset
settings of CLASSIC, NEWS, ROCK, POP, C/W
(Country/Western) or JAZZ. To return to the manual
mode, press and release this button until the AUTO
TONE display goes blank. This will return the tone
adjustment to the BASS and TREB controls. If a BASS
or TREB control is rotated, the AUTO TONE display
will go blank. Use PUSHBUTTONS to program
AUTO TONE.
Adjusting the Speakers
BAL: Press lightly on this knob to release it from its
stored position. Turn the control clockwise to adjust
sound to the right speakers and counterclockwise to
adjust sound to the left speakers. The middle position
balances the sound between the speakers.
FADE: Press lightly on this knob to release it from its
stored position. Turn the control clockwise to adjust the
sound to the front speakers and counterclockwise for the
rear speakers. The middle position balances the sound
between the speakers.
Push these knobs back into their stored positions when
you're not using them.

yellowblue
3-17
AM-FM: Press this button to switch from a tape to
the radio.
TAPE AUX: Press this button to return to the tape
player when playing the radio. The lighted arrow will
appear and show the direction of play when a tape is in
the active mode.
EJECT: Press this button to remove the tape. The radio
will now play. EJECT can be used with either the
ignition or radio off. To load a cassette tape with the
ignition or radio off, press EJECT before loading
the cassette.
CLN: If this message appears on the display, the
cassette tape player needs to be cleaned. It will still play
tapes, but you should clean it as soon as possible to
prevent damage to the tapes and player. See ªCare of
Your Cassette Tape Playerº in the Index. After you clean
the player, press and hold EJECT for five seconds to
reset the CLN indicator. The radio will display
--- to
show the indicator was reset.CD Adapter Kits
It is possible to use a CD adapter kit with your cassette
tape player after activating the bypass feature on your
tape player.
To activate the bypass feature, use the following steps:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio off.
3. Press and hold the TAPE AUX button for five
seconds. The tape symbol on the display will flash
for two seconds, indicating the feature is active.
4. Insert the adapter. It will power up the radio and
begin playing.
This override routine will remain active until EJECT
is pressed.

yellowblue
3-18 AM-FM Stereo with Compact Disc Player
and Automatic Tone Control (If Equipped)
Playing the Radio
PWR
-VOL: Press this knob to turn the system on and
off. To increase volume, turn this knob clockwise. Turn
it counterclockwise to decrease volume. The knob is
capable of rotating continuously.
RECALL: Display the time with the ignition off by
pressing this button. When the radio is playing, press
this button to recall the station frequency.SCV: Your system has a feature called
Speed
-Compensated Volume (SCV). With SCV, your
audio system adjusts automatically to make up for road
and wind noise as you drive. Set the volume at the
desired level. Turn the control ring behind the upper
knob clockwise to adjust the SCV. Then, as you drive,
SCV automatically increases the volume, as necessary,
to overcome noise at any particular speed. The volume
level should always sound the same to you as you drive.
If you don't want to use SCV, turn the control all the
way down. Each notch on the control ring allows for
more volume compensation at faster vehicle speeds.
Finding a Station
AM
-FM: Press this button to switch between AM, FM1
and FM2. The display will show your selection.
TUNE: Press this knob lightly so it extends. Turn it to
choose radio stations. Push the knob back into its stored
position when you're not using it.
SEEK: Press the right arrow to tune to the next higher
station and the left arrow to tune to the next lower
station and stay there. The sound will mute
while seeking.

yellowblue
3-19
SCAN: Press and hold SEEK for two seconds until
SCAN appears on the display. SCAN allows you to
listen to stations for a few seconds. The receiver will
continue to scan and momentarily stop at each station
until you press the button again. The sound will mute
while scanning.
PUSHBUTTONS: The six numbered pushbuttons let
you return to your favorite stations. You can set up to
18 stations (six AM, six FM1 and six FM2). Just:
1. Turn the radio on.
2. Press AM
-FM to select the band.
3. Tune in the desired station.
4. Press AUTO TONE to select the setting you prefer.
5. Press and hold one of the six pushbuttons. The sound
will mute. When it returns, release the button.
Whenever you press that numbered button, the
station you set will return and the tone you selected
will be automatically selected for that button.
6. Repeat the steps for each pushbutton.P.SCAN: The preset scan button lets you scan through
your favorite stations stored on your pushbuttons. Select
either the AM, FM1 or FM2 mode and then press
P.SCAN. It will scan through each station stored on your
pushbuttons and stop for a few seconds before continuing
to scan through all of the pushbuttons. Press P.SCAN
again or one of the pushbuttons to stop scanning to listen
to a specific stored station. P.SCAN will light up on the
display while in this mode. If one of the stations stored on
a pushbutton is too weak for the location you are in, the
radio display will show the channel number (P1
-P6) for
several seconds before advancing to the next preset station.
Setting the Tone
BASS: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase bass
and counterclockwise to decrease bass. When the BASS
control is rotated, the AUTO TONE display will go blank.
TREB: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase
treble and counterclockwise to decrease treble. When
the TREB control is rotated, the AUTO TONE display
will go blank. If a station is weak or noisy, you may
want to decrease the treble.
Push these knobs back into their stored positions when
you're not using them.

yellowblue
3-20
AUTO TONE: Press this button to select among the six
preset equalization settings and tailor the sound to the
music or voice being heard. Each time you press the
button, the selection will switch to one of the preset
settings of CLASSIC, NEWS, ROCK, POP, C/W
(Country/Western) or JAZZ. To return to the manual
mode, press and release this button until the AUTO
TONE display goes blank. This will return the tone
adjustment to the BASS and TREB controls. If a BASS
or TREB control is rotated, the AUTO TONE display
will go blank. Use PUSHBUTTONS to program
AUTO TONE.
Adjusting the Speakers
BAL: Press lightly on this knob to release it from its
stored position. Turn the control clockwise to adjust
sound to the right speakers and counterclockwise to
adjust sound to the left speakers. The middle position
balances the sound between the speakers.
FADE: Press lightly on this knob to release it from its
stored position. Turn the control clockwise to adjust the
sound to the front speakers and counterclockwise for the
rear speakers. The middle position balances the sound
between the speakers.
Push these knobs back into their stored positions when
you're not using them.Playing a Compact Disc
PWR: Press this knob to turn the system on.
(Please note that you can also turn the system on
when you insert a compact disc into the player with the
ignition on.)
Insert a disc partway into the slot, label side up. The
player will pull it in. Wait a few seconds and the disc
should play. CD and a CD symbol will also appear on
the display. Anytime you are playing a CD, the letters
CD will be next to the CD symbol.
If the disc comes back out and ERR appears on the
display, it could be that:

You are driving on a very rough road. (The disc
should play when the road gets smoother.)

The disc is upside down.

It is dirty, scratched or wet.

It is very humid. (If so, wait about an hour and
try again.)

The disc player is very hot.
Press RECALL to make ERR go off the display.

yellowblue
3-27 Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren't, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLN to indicate
that you have used your tape player for 50 hours without
resetting the tape clean timer. If this message appears on
the display, your cassette tape player needs to be
cleaned. It will still play tapes, but you should clean it as
soon as possible to prevent damage to your tapes and
player. If you notice a reduction in sound quality, try a
known good cassette to see if it is the tape or the tape
player at fault. If this other cassette has no improvement
in sound quality, clean the tape player.
The recommended cleaning method for your cassette
tape player is the use of a scrubbing action,
non
-abrasive cleaning cassette with pads which scrub
the tape head as the hubs of the cleaner cassette turn.
The recommended cleaning cassette is available through
your dealership (GM Part No. 12344789).When using a scrubbing action, non
-abrasive cleaning
cassette, it is normal for the cassette to eject because
your unit is equipped with a cut tape detection feature
and a cleaning cassette may appear as a broken tape. To
prevent the cleaning cassette from being ejected, use the
following steps.
If your vehicle is equipped with the AM
-FM Stereo with
Cassette Tape Player:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio on.
3. Insert the scrubbing action cleaning cassette.
4. Within five seconds, press and hold the REV and
FWD buttons at the same time for three seconds. The
tape symbol on the display will flash, showing that
the cut tape detection feature is no longer active.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.