RAM CHASSIS CAB 2012 Owners Manual
Manufacturer: RAM, Model Year: 2012, Model line: CHASSIS CAB, Model: RAM CHASSIS CAB 2012Pages: 502, PDF Size: 3.96 MB
Page 261 of 502

Recirculation Control
Press this button to choose between
outside air intake or recirculation of
the air inside the vehicle. A LED will
illuminate when you are in Recircula-
tion mode. Only use the Recirculation
mode to temporarily block out any
outside odors, smoke, or dust, and to
cool the interior rapidly upon initial start-up in very hot
or humid weather.
NOTE:
• If the RECIRCULATION button is pressed when the
system is in Mix or Defrost mode the Recirculation
LED indicator will flash three times and then turn off
to indicate Recirculation mode is not allowed.
• Continuous use of the Recirculation mode may make
the inside air stuffy and window fogging may occur.
Extended use of this mode is not recommended. • In cold or damp weather, the use of the Recirculation
mode will cause windows to fog on the inside because
of moisture buildup inside the vehicle. For maximum
defogging, select the outside air position.
• The A/C can be deselected manually without disturb-
ing the mode control selection by pressing the A/C
button.
Air Outlets
The airflow from each of the instrument panel outlets can
be adjusted for direction, and turned on or off to control
airflow.
NOTE: For maximum airflow to the rear, the center
instrument panel outlets can be directed toward the rear
seat passengers.
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Economy Mode
If ECONOMY mode is desired, press the A/C button to
turn off the LED indicator and the A/C compressor.
Rotate the temperature control knob to the desired
temperature.
Air Conditioning Operation
Push this button to engage the Air
Conditioning (A/C). A LED will illu-
minate when the A/C system is
engaged. MAX A/C
For maximum cooling, when MAX
A/C is selected the A/C is turned on
automatically and the air is recircu-
lated.
NOTE: A/C cannot be deselected when in MAX A/C
position. The LED will blink three times if the A/C
button is pushed.
Automatic Temperature Control (ATC) — If
Equipped
• The Automatic Temperature Control (ATC) allows
both driver and front passenger seat occupants to
select individual comfort settings.260 UNDERSTANDING YOUR INSTRUMENT PANEL
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• When occupants in the vehicle select an Auto mode
operation, Auto blower operation is set by using rotary
knobs on the control unit and a comfort temperature
setting by using the temperature up and down but-
tons.
• The system provides set-and-forget operation for op-
timum comfort and convenience.
• The system can be controlled manually, if desired.
• SYNC feature links the temperature controls, the pas-
senger side temperature becomes the same as the
temperature selected by the driver.
The ATC system automatically maintains the interior
comfort level desired by the driver and all passengers. Automatic Temperature Control (ATC) Panel 1 - Blower Control 9 - DEFROST
2 - Left Temperature Up 10 - Right Temperature Down
3 - SYNC Indicator 11 - A/C
4 - Left Temperature Indicator 12 - A/C Indicator
5 - Right Temperature Indicator 13 - SYNC Temperature Button
6 - DELAY Indicator 14 - Left Temperature Down
7 - Right Temperature Up 15 - RECIRCULATE
8 - MODE
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Automatic Operation
1. Position the MODE control knob to the Auto position
on the Automatic Temperature Control (ATC) Panel.
2. Position the BLOWER control knob in the Auto posi-
tion on the ATC Panel.
3. Next, adjust the temperature you would like the
system to maintain by adjusting the driver and front
passenger temperature buttons. Once the desired tem-
perature is displayed, the system will achieve and auto-
matically maintain that comfort level.
4. When the system is set up for your comfort level, it is
not necessary to change the settings. You will experience
the greatest efficiency by simply allowing the system to
function automatically. NOTE:
• It is not necessary to move the temperature settings for
cold or hot vehicles. The system automatically adjusts
the temperature, mode and fan speed to provide
comfort as quickly as possible.
• The temperature can be displayed in U.S. or Metric
units by selecting the US/M customer-programmable
feature. Refer to the “Electronic Vehicle Information
Center (EVIC) — Customer-Programmable Features
(SETUP)” in this section of the manual.
To provide you with maximum comfort in the Automatic
mode, during cold start-ups the blower fan will remain
on low and the DELAY symbol will appear in the ATC
display until the engine warms up. The blower will
increase in speed and transition into Auto mode and
DELAY will no longer be illuminated in the display. The262 UNDERSTANDING YOUR INSTRUMENT PANEL
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blower will engage immediately if the Defrost mode is
selected, or by adjusting the blower control knob and
setting the fan to any fixed speed.
Manual Operation
This system offers a full complement of manual override
features.
NOTE: Each of these features operate independently
from each other. If any one feature is controlled manually,
the temperature doors will continue to operate automati-
cally.
There are six fixed blower speeds. Use
this control to regulate the amount of
air forced through the system in any
mode you select. The blower speed
increases as you move the control
clockwise from the OFF position. The blower fan speed can be set to any fixed speed by
adjusting the blower control knob. The fan will now
operate at a fixed speed until additional speeds are
selected. This allows the front occupants to control the
volume of air circulated in the vehicle and cancel the
Auto mode.
The operator can also select the direction of the airflow
by selecting one of the following positions.
Panel Mode
Air comes from the outlets in the instrument panel.
Each of these outlets can be individually adjusted to
direct the flow of air. The air vanes of the center outlets
and outboard outlets can be rotated to regulate or shut off
the airflow from these outlets.
Bi-Level Mode
Air comes from the instrument panel outlets, floor
outlets and defrost outlets.Blower Control
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NOTE: In many temperature positions, the BI-LEVEL
mode is designed to provide cooler air out of the panel
outlets and warmer air from the floor outlets.
Floor Mode
Air comes from the floor outlets. A slight amount of
air is directed through the defrost and side window
demister outlets.
Mix Mode
Air comes from the floor, defrost and side window
demist outlets. This mode works best in cold or
snowy conditions. It allows you to stay comfortable
while keeping the windshield clear.
Defrost Mode
Air comes from the windshield and side window
demist outlets. Use Defrost mode with maximum
blower and temperature settings for best windshield and
side window defrosting. NOTE: While operating in the other modes, the system
will not automatically sense the presence of fog, mist or
ice on the windshield. Defrost mode must be manually
selected to clear the windshield and side glass.
The Air Conditioning (A/C) button allows the
operator to manually activate or deactivate the air
conditioning system. When in A/C mode and the
ATC is set to a cool temperature, dehumidified air flows
through the air outlets. If Economy mode is desired, press
the A/C button to turn off the A/C mode in the ATC
display and deactivate the A/C system.
NOTE:
• If the system is in Mix, Bi-Level or Defrost Mode, the
A/C can be turned off, but the A/C system shall
remain active to prevent fogging of the windows.
• If fog or mist appears on the windshield or side glass,
select Defrost mode and increase blower speed.264 UNDERSTANDING YOUR INSTRUMENT PANEL
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Recirculation Control
When outside air contains smoke, odors, or
high humidity, or if rapid cooling is desired,
you may wish to recirculate interior air by
pressing the RECIRCULATION control button.
Recirculation mode should only be used temporarily. The
recirculation LED will illuminate on the blower control
knob when this button is selected. Push the button a
second time to turn off the Recirculation mode LED and
allow outside air into the vehicle.
NOTE: In cold weather, use of Recirculation mode may
lead to excessive window fogging. The Recirculation
mode is not allowed in the Floor/Defrost Mix and
Defrost modes to improve window clearing operation.
Recirculation will be disabled automatically if these
modes are selected. Summer Operation
The engine cooling system in air conditioned vehicles
must be protected with a high-quality antifreeze coolant
to provide proper corrosion protection and to protect
against engine overheating. A solution of 50% ethylene
glycol antifreeze coolant and 50% water is recommended.
Refer to “Maintenance Procedures” in “Maintaining Your
Vehicle” for proper coolant selection.
Winter Operation
To ensure the best possible heater and defroster perfor-
mance, make sure the engine cooling system is function-
ing properly and the proper amount, type, and concen-
tration of coolant is used. Refer to “Maintenance
Procedures” in “Maintaining Your Vehicle” for proper
coolant selection. Use of the air Recirculation mode
during Winter months is not recommended because it
may cause window fogging.
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Vacation/Storage
Any time you store your vehicle or keep it out of service
(i.e., vacation) for two weeks or more, run the air
conditioning system at idle for about five minutes in
fresh air with the blower setting in high. This will ensure
adequate system lubrication to minimize the possibility
of compressor damage when the system is started again.
Window Fogging and Frosting
Vehicle windows tend to fog on the inside of the glass in
mild, rainy and/or humid weather. Windows may frost
on the inside of the glass in very cold weather. To clear
the windows, select Defrost or Mix mode and increase
the front blower speed. Do not use the Recirculation
mode without A/C for long periods, as fogging may
occur. Outside Air Intake
Make sure the air intake, located directly in front of the
windshield, is free of obstructions such as leaves. Leaves
collected in the air intake may reduce airflow, can cause
odor, and if they enter the plenum they could plug the
water drains. In Winter months make sure the air intake
is clear of ice, slush and snow.266 UNDERSTANDING YOUR INSTRUMENT PANEL
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Operating Tips
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