2008 DODGE RAM 3500 DIESEL air conditioning

NSatellite Antenna......................245
NReception Quality.....................245
mRemote Sound System Controls Ð If Equipped . . 246
NRadio Operation......................246
NTape Player.........................247
NCD Player..........................247
mCassette Tape And Player Maintenance.......247
mCompact Disc Maintenance................248
mRadio Operation And Cellular Phones........249mClimate Controls.......................249
NHeater Only Ð If Equipped..............250
NAir Conditioning And Heating Ð
If Equipped.........................252
NAir Conditioning With Dual Zone Temperature
Control Ð If Equipped.................255
NOperating Tips.......................260
NOperating Tips Chart...................262
186 UNDERSTANDING YOUR INSTRUMENT PANEL

Air Conditioning and Heating Ð If Equipped
Air Conditioning Operation
To turn on the Air Conditioning, set the fan
control at any speed and press the snowflake
button located at the right of the control panel.
Conditioned air will be directed through theoutlets selected by the mode control. A light in the
snowflake button shows that the air conditioning is on.
Press the button a second time to turn the air condition-
ing off.
Slight changes in engine speed or power may be noticed
when the air conditioning compressor is on. This is a
normal occurrence as the compressor will cycle on and
off to maintain comfort and increase fuel economy.
The mode control (at the right of the
control panel) can be set in any of the
following positions:
Air Conditioning And Heating
252 UNDERSTANDING YOUR INSTRUMENT PANEL

NOTE:To improve your selection choices, the system
allows you to operate at intermediate positions between
the major modes. These intermediate positions are iden-
tified by the small dots.
Recirculation Modes (Panel or Bi-Level)
Select the recirculation modes when
the outside air contains smoke, odors,
high humidity, or if rapid cooling is
desired. This feature allows for recir-
culation of interior air only. Air flows
through the panel only, or through
both the panel and floor vents depend-
ing on the selected mode (panel vs
bi-level).
NOTE:Selecting a Recirculation Mode does not neces-
sarily consume more fuel than normal A/C mode.
Panel
Outside air flows through the outlets located in the
instrument panel.
Bi-Level
Outside air flows through the outlets located in the
instrument panel and at the floor.
Floor
Outside air flows primarily through the floor out-
lets located under the instrument panel.
Mix
Outside air flows in equal proportions through the
floor and defroster outlets, and the air conditioning
may be on.
Defrost
Outside air is primarily directed to the windshield
through the defroster outlets located at the base of
UNDERSTANDING YOUR INSTRUMENT PANEL 253
4

the windshield, and the demister outlets located at the
edge of each side of the instrument panel, and the air
conditioning may be on.
NOTE:The air conditioning compressor operates in
both Mix and Defrost or a blend of these modes, even if
the A/C button has not been pressed. This dehumidifies
the air to help dry the windshield.
Blower Control
The rotary knob on the left of the
control panel is the blower control.
Turn the knob clockwise to one of the
four positions to obtain the blower
speed you desire. To turn the blower
off, turn the knob to the far left posi-
tion.
Temperature Control
The rotary knob at the center of the
control panel controls the temperature
of the interior air. You can choose your
degree of comfort by rotating the
knob. The coldest temperature setting
is to the extreme left (blue region) and
the warmest setting is to the extreme
right (red region) of the rotation.
Circulation
The cab is designed with features to promote outside air
circulation. There are grilles in the cab back panel. These
are air exhausters that provide the means for regular
exchange of cab air.
254 UNDERSTANDING YOUR INSTRUMENT PANEL

Side window demisters direct airflow specifically to the
window glass to help prevent interior fogging of the
glass. They are located in the extreme outside upper
edges of the instrument panel. The demisters also pro-
vide extra air ducts for circulation. They are in operation
whenever the Floor, Mix or Defrost modes are in use. To
remove frost from the side windows, it is best to use the
full defrost mode.
NOTE:When you turn off the engine you may hear a
hissing sound from under the hood for a short period of
time. This is a normal condition that occurs if the air
conditioning system has been on. It is not an indication of
a problem with the air conditioning system.Air Conditioning with Dual Zone Temperature
Control Ð If Equipped
With the Dual Zone Temperature Control System, each
front seat occupant can independently control the tem-
perature of air coming from the outlets on their side of
the vehicle.
Dual Zone Control Head
UNDERSTANDING YOUR INSTRUMENT PANEL 255
4

Air Conditioning and Heating Operation
To turn on the Air Conditioning, set the fan control at any
speed and press the snowflake button located on the
control panel. Conditioned air will be directed through
the outlets selected by the mode control. A light in the
snowflake button shows that the air conditioning is on.
Press the button a second time to turn the air condition-
ing off.
A/C Pushbutton
With the fan control in the ON posi-
tion, pushing the A/C button turns on
the air conditioning compressor. An
indicator light on the button shows
that the Air Conditioning compressor
is on. Conditioned air is now directed
through the mode outlets selected.
Pushing the button a second time turns the compressor
OFF.
Recirculation Pushbutton
Pushing the Recirculation button al-
lows interior air to recirculate continu-
ously in any position except defrost
and defrost/floor mode for rapid cool
down of the interior. See ªFast
Cooldownº later in this section.
Mode Control
The mode control allows you to
choose from several patterns of air
distribution.
256 UNDERSTANDING YOUR INSTRUMENT PANEL

NOTE:To improve your selection choices, the system
allows you to operate at intermediate positions between
the major modes. These intermediate positions are iden-
tified by the small dots and give an even blend of both
modes.
Panel
Outside air flows through the outlets located in the
instrument panel. These outlets can be adjusted to
direct the airflow.
Bi-Level
Air flows through the outlets located in the instru-
ment panel and those located on the floor.
NOTE:There is a difference in temperature between the
upper and lower outlets for added comfort. The warmer
air goes to the floor outlets. This feature gives improved
comfort during sunny but cool conditions.
Heat
Outside air flows primarily through the floor out-
lets located under the instrument panel.
Mix
Outside air flows in equal proportions through the
floor and defroster outlets.
Defrost
Outside air is primarily directed to the windshield
through the defroster outlets located at the base of
the windshield and side window demist outlets.
NOTE:The air conditioning compressor operates in
both Mix and Defrost or a blend of these modes, even if
the A/C button has not been pressed. This dehumidifies
the air to help dry the windshield.
UNDERSTANDING YOUR INSTRUMENT PANEL 257
4

Circulation
The cab is designed with features to promote outside air
circulation. There are grilles in the cab back panel. These
are air exhausters that provide the means for regular
exchange of cab air.
Side window demisters direct airflow specifically to the
window glass to help prevent interior fogging of the
glass. They are located in the extreme outside upper
edges of the instrument panel. The demisters also pro-
vide extra air ducts for circulation. They are in operation
whenever the Floor, Mix or Defrost modes are in use.
NOTE:When you turn off the engine you may hear a
hissing sound from under the hood for a short period of
time. This is a normal condition that occurs if the air
conditioning system has been on. It is not an indication of
a problem with the air conditioning system.
Rear Air Duct (Mega Cab Only) Ð If Equipped
The rear seat will receive airflow in all modes except for
Defrost.
The rear air duct is designed to be pointed up when in
A/C mode, and pointed down in Heat mode.
Mega Cab Rear Air Duct
UNDERSTANDING YOUR INSTRUMENT PANEL 259
4