Exhaust Restrictor
(DURAMAX
®Diesel)
If your vehicle is equipped with a DURAMAX®6600
engine, it has a cold temperature high idle feature which
elevates the engines idle speed from 660 to 1500 rpms,
and restricts the exhaust gas flow, when outside
temperatures are below 32°F (0°C), and the engine
coolant temperature is below 150°F (65°C). This feature
enhances heater performance by raising the engine
coolant temperature faster.
This feature is already turned on. This feature can be
turned off and on by doing the following brake stomp
procedure:
1. Turn the ignition to RUN, with the vehicle off.
2. Press the accelerator pedal to the floor and
hold while quickly pressing the brake pedal
three times in less than eight seconds.
3. Release the accelerator pedal and start
the engine.If this feature is turned on when the engine is started,
the green exhaust brake/restrictor light below the
radio controls will be lit for 10 seconds. If this feature is
turned on and the algorithm comes on, based upon
the temperature conditions and other conditions, then
the green exhaust brake/restrictor light will remain lit and
the engine will slowly ramp up to the high idle speed
after a delay of a few seconds up to approximately
two minutes.
When the engine is started, it will slowly ramp up to the
high idle speed after a delay of a few seconds up to
about two minutes. For this method to work properly
there must be no throttle or brake pedal faults, and the
throttle pedal must not fall below 75 percent of wide
open throttle while pressing the brake pedal.
The engine idle speed will return to normal once the
following conditions are met:
•Once engine coolant temperature reaches
150°F (65°C).
•Air intake temperature reaches 41°F (5°C).
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Air Brake
If your vehicle has air
brakes, you will have
this parking brake.
It is located above
the radio in the
instrument panel.
Pulling it out applies the parking brake. The park brake
light will come on when the air parking brake is applied.Vehicles built for use as tractors or towing vehicles have
two air brake controls. They look like this:
{CAUTION:
When the yellow PARKING BRAKE and the red
TRAILER AIR SUPPLY knobs are both pushed
in, your rig will be free to move. It could strike
someone or something. When both of these
knobs are pushed in, hold the regular brake
pedal down to keep your rig from moving.
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Marker Lamps
If your vehicle has this feature, you can manually blink
the marker and clearance lamps.
The marker lamp defeat
switch is located in the
instrument panel
switchbank.
Press and hold the bottom of the switch to turn off the
marker and clearance lamps. When you release
the switch, the marker and clearance lamps will come
back on.
Instrument Panel Brightness
This feature controls the brightness of the instrument
panel lights.
The thumbwheel for this feature is located to the right of
the exterior lamp control.
Turn the thumbwheel up to brighten the lights. When
the thumbwheel is moved to the first position, the radio
display and transmission selection display will go to
full intensity. The instrument panel cluster will also be
dimly lit. Moving the thumbwheel up to the next position
will activate the interior dome lamps.
Dome Lamps
The dome lamps will come on when you open a door.
You can also turn the dome lamps on by moving
the thumbwheel, located to the right of the exterior lamp
control, all the way up to the second position. In this
position, the dome lamps will remain on whether a door
is open or closed.
You can use the dome override button to set the dome
lamps to automatically come on when a door is
open, or to remain off.
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Notice:The chime signals related to seat belts,
parking brake, and other functions of your vehicle
operate through the GM radio/entertainment system.
If that equipment is replaced or additional
equipment is added to your vehicle, the chimes may
not work. Make sure that replacement or additional
equipment is compatible with your vehicle before
installing it.
Figure out which audio system is in your vehicle, find
out what your audio system can do, and how to operate
all of its controls.
Setting the Time
Press and hold the HR (down) or MIN (up) arrow for
two seconds. Then press HR until the correct hour
appears on the display. Press and hold MIN until the
correct minute appears on the display. The time can be
set with the ignition on or off.
AM-FM Radio
Playing the Radio
PWR (Power):Press this knob to turn the system on
and off.
VOL (Volume):Turn this knob to increase or to
decrease the volume.
RCL (Recall):Press this knob to switch the display
between the radio station frequency, band, and the
time. When the ignition is off, press this knob to display
the time.
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To adjust both tone controls and both speaker controls
to the middle position, first end out of audio mode
by pressing another button, causing the radio to perform
that function or by waiting five seconds for the display
to return to time of day. Then press and hold AUDIO for
more than two seconds until you hear a beep. CEN
will appear on the display.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the right
and the left speakers, press and release AUDIO until
BAL appears on the display. Then press and hold the up
or the down arrow to move the sound toward the right
or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD appears
on the display. Then press and hold the up or the
down arrow to move the sound toward the front or the
rear speakers.
To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L (balance) and
a zero or F and a zero will appear on the display.To adjust both tone controls and both speaker controls
to the middle position, first end out of audio mode
by pressing another button, causing the radio to perform
that function or by waiting five seconds for the display
to return to time of day. Then press and hold AUDIO for
more than two seconds until you hear a beep. CEN
will appear on the display.
Fade may not be available if the vehicle is a regular
cab model.Radio Messages
CAL (Calibrated):The audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that the radio has not
been configured properly for your vehicle and must
be returned to your GM dealer for service.
LOC (Locked):This message is displayed when the
THEFTLOCK
®system has locked up. Take the vehicle
to your GM dealer for service.
If any error occurs repeatedly or if an error cannot be
corrected, contact your GM dealer.
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Setting Preset Stations
Up to 18 stations (six FM1, six FM2, and six AM) can be
programmed on the six numbered pushbuttons, by
performing the following steps:
1. Turn the radio on.
2. Press AM FM to select FM1, FM2, or AM.
3. Tune in the desired station.
4. Press and hold one of the six numbered
pushbuttons until you hear a beep. Whenever that
numbered pushbutton is pressed, the station
that was set will return.
5. Repeat the steps for each pushbutton.
Setting the Tone (Bass/Treble)
AUDIO:To adjust bass and treble, press and release
AUDIO until BAS or TRE appears on the display.
Then press and hold the up or the down arrow to
increase or to decrease. If a station is weak or noisy,
decrease the treble.
To adjust bass or treble to the middle position, select
BAS or TRE. Then press and hold AUDIO for more than
two seconds until you hear a beep. B and a zero or
T and a zero will appear on the display.
To adjust both tone controls and both speaker controls
to the middle position, end out of audio by waiting
for the display to change to the clock display. Then
press and hold AUDIO for more than two seconds until
you hear a beep. CEN will appear on the display.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the right
and the left speakers, press and release AUDIO until
BAL appears on the display. Then press and hold the up
or the down arrow to move the sound toward the right
or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD appears
on the display. Then press and hold the up or the
down arrow to move the sound toward the front or the
rear speakers.
To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L (balance) and
a zero or F and a zero will appear on the display.
To adjust both tone controls and both speaker controls
to the middle position, end out of audio by waiting
for the display to change to the time display. Then press
and hold AUDIO for more than two seconds until you
hear a beep. CEN will appear on the display.
Fade may not be available if the vehicle is a regular
cab model.
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Radio Messages
CAL (Calibration):The audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that the radio has not
been configured properly for your vehicle and must
be returned to your GM dealer for service.
LOC (Locked):This message is displayed when the
THEFTLOCK
®system has locked up. Take the vehicle
to your GM dealer for service.
If any error occurs repeatedly or if an error cannot be
corrected, contact your GM dealer.
Playing a Cassette Tape
The 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. The longer side with the tape visible should
face to the right. If you hear nothing or hear a garbled
sound, the tape may not be in squarely. Press the eject
button to remove the tape and start over.
If the ignition and the radio are off, press the eject
button or the RCL knob to insert and to begin play of a
tape. If the ignition is on and the radio is off, the
tape can be inserted and will begin playing. CAS will
appear on the display when a tape is inserted.While the tape is playing, use the VOL, AUDIO, and
SEEK controls just as you do for the radio. The radio will
display UP if the top side of the tape is playing.
DN (Down) will appear if the bottom side is playing. The
tape player will play the other side of the tape when it
reaches the end.
Cassette tape adapter kits for portable CD players will
work in the cassette tape player. See “CD Adapter Kits”
later for more information.
The tape bias is set automatically when a metal or
chrome tape is inserted.
If an error appears on the display, see “Cassette Tape
Messages” later in this section.
1 PREV (Previous):The tape must have at least
three seconds of silence between each selection for
previous to work. Press this pushbutton to go to
the previous selection on the tape if the current selection
has been playing for less than three seconds. If
pressed when the current selection has been playing
from three to 13 seconds, it will go to the beginning
of the previous selection or the beginning of the current
selection, depending on the position on the tape. If
pressed when the current selection has been playing for
more than 13 seconds, it will go to the beginning of
the current selection. Pressing this pushbutton multiple
times will increase the number of selections to be
searched back, up to−9. Pressing the NEXT pushbutton
will cancel the selections.
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2 NEXT:The tape must have at least three seconds of
silence between each selection for next to work.
Press this pushbutton to go to the next selection on the
tape. Pressing this pushbutton multiple times in the
next mode will increase the number of selections to be
searched forward. Pressing the PREV pushbutton
will cancel the selections.
3 REV (Reverse):Press this pushbutton to quickly
reverse the tape. FR will appear on the display.
The radio will play while the tape reverses. Press it
again to return to playing speed. Select stations during
reverse operation by using the TUNE or SEEK
controls or by using the scan or preset scan features.
4 FWD (Forward):Press this pushbutton to quickly
advance the tape. FF will appear on the display.
The radio will play while the tape advances. Press this
pushbutton again to return to playing speed. Select
stations during forward operation by using the TUNE or
SEEK controls or by using the scan or preset scan
features.
5 SIDE:Press this pushbutton to play the other side of
the tape.6 RPT (Repeat):The tape must have at least
three seconds of silence between each selection for
repeat to work. Press and release this pushbutton
to hear a selection over again. RPT will appear on the
display. Press this pushbutton again to turn off repeated
play. OFF will appear on the display.
oSEEKp:The tape must have at least
three seconds of silence between each selection for
seek to work. The left arrow is the same as the PREV
pushbutton and the right arrow is the same as the NEXT
pushbutton. If either arrow is held or pressed more
than once, the player will continue moving backward or
forward through the tape.
AM FM:Press this button to listen to the radio when a
tape is playing. The inactive tape will remain safely
inside the radio for future listening.
TAPE:Press this button to play a cassette tape when
listening to the radio. CAS will appear on the display
when a tape is loaded.
Z(Eject):Press this button to eject a tape. Eject
may be activated with the radio off. Cassette tapes can
be loaded with the ignition and radio off if this button
is pressed first.
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