2004 DODGE RAM 2500 DIESEL engine

Temperature Control
The rotary knob at the center
of the control panel controls
the temperature of the inte-
rior air. You can choose your
degree of comfort by rotating
the knob. The coldest tem-
perature setting is to the ex-
treme 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.Side window demisters direct air flow 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.
190 UNDERSTANDING YOUR INSTRUMENT PANEL

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.
Operating Tips
Fast Cooldown
For a fast cooldown, turn the blower fan rotary knob to
the extreme right position, turn the mode control to the
panel fresh position, press the snowflake button to turn
on the air conditioning, and drive with the windows
open for the first few minutes. Once the hot air has been
expelled, close the windows and press the Recirculation
pushbutton. When a comfortable condition has beenreached, choose a mode position and adjust the tempera-
ture control slide and blower speed as necessary to
maintain comfort. For high humidity conditions it may
be necessary to remain in the Recirculation mode to
maintain comfort.
Window Fogging
Windows will fog on the inside when the humidity inside
the vehicle is high. This often occurs in mild or cool
temperatures when it's rainy or humid. In most cases
turning on the Air-conditioning (pressing the snowflake
button) will clear the fog. Adjust the temperature control,
air direction and blower speed to maintain comfort.
As the temperature gets colder it may be necessary to
direct air onto the windshield by using MIX Mode
position on the control. Adjust the temperature control
and blower speed to maintain comfort. Higher blower
196 UNDERSTANDING YOUR INSTRUMENT PANEL

speeds will reduce fogging. Interior fogging on the
windshield can be quickly removed by selecting the
defrost mode.
Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to Recommended
Fluids and Genuine Parts for the proper coolant type.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation isencountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift into
NEUTRAL and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.
NOTE:On models equipped with Diesel engines, the
idle speed will automatically increase to 1000 rpm at
elevated coolant temperatures to improve engine cooling.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions.
UNDERSTANDING YOUR INSTRUMENT PANEL 197
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STARTING AND OPERATING
CONTENTS
mIgnition/Starter Switch...................204
NLock..............................204
NOff ...............................204
NOn................................204
NStart..............................204
NACC ..............................205
NManual Transmission Key Release Button....205
NKey Reminder.......................205
mStarting Procedures.....................205NNormal Starting Procedure Ð Engine
Manifold Airtemperature Above 66ÉF (19ÉC) . . 206
NStarting Procedure Ð Engine Manifold Air
Temperature Below 66ÉF (19ÉC)...........207
NStarting Fluids.......................210
mNormal Operation......................211
NCold Weather Precautions...............211
NEngine Idling Ð In Cold Weather..........214
NStopping The Engine...................215
NEngine Speed Control..................216
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NTire Loading And Tire Pressure...........247
mTiresÐGeneral Information................251
NTire Pressure.........................251
NTire Inflation Pressures.................252
NRadial-Ply Tires......................255
NCompact Spare Tire Ð If Equipped.........255
NTire Spinning........................256
NTread Wear Indicators..................257
NReplacement Tires.....................257
NAlignment And Balance.................258
mSupplemental Tire Pressure Information.......259
mTire Chains...........................259
mSnow Tires...........................261mTire Rotation Recommendations............261
NDual Rear Wheels.....................263
mEngine Runaway.......................264
mFuel Requirements......................264
NAdding Fuel.........................265
NBulk Fuel Storage.....................267
NFuel Specifications....................267
mVehicle Loading........................269
NCertification Label.....................269
mTrailer Towing.........................272
NTo Maintain Warranty Coverage...........272
NAxle Lubricant And Trailer Towing.........274
NTrailer Towing Recommendations..........274
STARTING AND OPERATING 201
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mDriving Off-Road.......................292
mTraction.............................293mEngine Data Plate......................294
STARTING AND OPERATING 203
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IGNITION/STARTER SWITCH
LOCK
Locks the automatic transmission shift control into the
PARK position. It also engages the steering wheel lock (if
equipped) when the steering wheel is turned.NOTE: This vehicle is equipped with a transmission
shift interlocking system. The brake pedal must be
depressed to shift out of Park (P).
OFF
Unlocks the steering wheel (if equipped with locking
wheel) and the automatic transmission shift control with
engine off.
ON
This is the normal running position.
START
Starts the engine. When the engine starts, release the key.
The ignition key will return to the ON position for
normal driving.
204 STARTING AND OPERATING

ACC
Allows the electrical accessories to be used when the
engine is not running.
Manual Transmission Key Release Button
To remove the key on vehicles equipped with manual
transmissions, turn the key to the Lock position and press
the button to remove the ignition key.
Key Reminder
An alarm will sound to remind you if the key is left in the
ignition and the driver's door is opened.
STARTING PROCEDURES
The Cummins Diesel engine is equipped with several
features designed to assist cold weather starting and
operation:
²The engine block heater is a resistance heater installed
in the water jacket of the engine just above and behind
the oil filter. It requires a 110±115 volt AC electrical
outlet with a grounded, three-wire extension cord.
NOTE:The engine block heater cord is a factory in-
stalled option. If your vehicle is not equipped, heater
cords are available from your authorized Mopartdealer.
²A 12±volt heater built into the fuel filter housing aids
in preventing fuel gelling. It is controlled by a built-in
thermostat.
STARTING AND OPERATING 205
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