2004 DODGE RAM 2500 DIESEL check engine

Do not remove the top of the air filter housing to
inspect the filter element on your diesel engine under
normal operating conditions.
The clear plastic housing on the Filter MinderŸ allows
you to view the amount of air pressure drop across the
filter element. It consists of a diaphragm and a calibrated
spring sealed inside the plastic housing. As the aircleaner filter becomes clogged and air pressure drop
across the filter element increases, a yellow disc travels
along a graduated scale on the side of the Filter
MinderŸ.
The yellow disc will always show the greatest restriction
experienced by the filter element. When the disc reaches
the red zone, the filter element may need to be replaced.
There is no other time or mileage interval for changing
the air cleaner filter element.
If the vehicle experiences a sudden loss of engine power
when being driven in heavy snow or rain or when
plowing snow, check the Filter MinderŸ
²If the Filter MinderŸ is showing a plugged filter, the
filter should be visually inspected for snow/ice build
up or extreme water saturation.
²If any of these conditions exist, the filter element
should be replaced.
332 MAINTAINING YOUR VEHICLE

Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0ÉF (-18É). For the same de-
crease in temperature, the engine requires twice as much
power to crank at the same RPM. The use of 120 VAC
powered battery blankets will greatly increase starting
capability at low temperatures. Suitable battery blankets
are available from your authorized Mopartdealer.
Air Conditioner Maintenance
For best possible performance, your air conditioner
should be checked and serviced by an Authorized Dealer
at the start of each warm season. This service should
include cleaning of the condenser fins and a performance
test. Drive belt tension should also be checked at this
time.
WARNING!
²Use only refrigerants and compressor lubricants
approved by the manufacturer for your air condi-
tioning system. Some unapproved refrigerants are
flammable and can explode, injuring you. Other
unapproved refrigerants or lubricants can cause
the system to fail, requiring costly repairs.
²The air conditioning system contains refrigerant
under high pressure. To avoid risk of personal
injury or damage to the system, adding refrigerant
or any repair requiring lines to be disconnected
should be done by an experienced repairman.
338 MAINTAINING YOUR VEHICLE

Refrigerant Recovery and Recycling
R-134a Air Conditioning Refrigerant is a hydrofluorocar-
bon (HFC) that is endorsed by the Environmental Pro-
tection Agency and is an ozone-saving product. How-
ever, the manufacturer recommends that air conditioning
service be performed by dealers or other service facilities
using recovery and recycling equipment.
NOTE:Air Conditioning systems found to be contami-
nated with A/C System Sealers, Stop Leak Products, Seal
Conditioners, Compressor Oil, or Refrigerants not ap-
proved by the manufacturer, voids the warranty for the
Air Conditioning system.
Power Steering Ð Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises areapparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
DaimlerChrysler Dealership.9
WARNING!
Fluid level should be checked on a level surface and
with the engine off to prevent injury from moving
parts and to insure accurate fluid level reading. Do
not overfill. Use only manufacturers recommended
power steering fluid.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces. Refer to Recommended Fluids, Lubricants, and
Genuine Parts for correct fluid type.
MAINTAINING YOUR VEHICLE 339
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Windshield Wiper Blades
The rubber edges of the wiper blades and the windshield
should be cleaned periodically with a sponge or soft cloth
and a mild nonabrasive cleaner. This will remove accu-
mulations of salt or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.
Avoid using the wiper blades to remove frost or ice from
the windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Windshield Washers
The fluid reservoir is located under the hood and should
be checked for fluid level at regular intervals. Fill the
reservoir with windshield washer solvent only (not ra-
diator antifreeze).To prevent freeze-up of your windshield washer system
in cold weather, select a solution or mixture that meets or
exceeds the temperature range of your climate. This
rating information can be found on most washer fluid
containers.
WARNING!
Commercially available windshield washer solvents
are flammable. They could ignite and burn you. Care
must be exercised when filling or working around
the washer solution.
After the engine has warmed, operate the defroster for a
few minutes to reduce the possibility of smearing or
freezing the fluid on the cold windshield. Mopar All
Weather Windshield Washer Solution, used with water as
MAINTAINING YOUR VEHICLE 341
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Cooling System
Cooling System Maintenance
At the intervals shown in the Maintenance Schedules
Section of the manual, the system should be drained,
flushed and filled.
Inspection
Coolant protection checks should be made every 12
months (prior to the onset of freezing weather, where
applicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant as specified.
Inspect the entire cooling system for leaks. Check the face
of the radiator for any accumulation of bugs, leaves, or
other foreign matter. If dirty, clean the radiator core with
a garden hose. With the engine OFF, gently spray water
from the back of the radiator core. Check coolant bottle
tube for condition and tightness of connections at coolant
bottle and radiator.Check the coolant pressure cap and coolant bottle for
proper vacuum sealing. With the engine at normal oper-
ating temperature, note the level of the coolant in the
coolant bottle. Without removing the pressure cap (with
the engine off), drain a small amount of coolant from the
radiator drain cock. If the coolant level in the coolant
bottle drops, the system is sealing properly.
Extremely cold ambient temperature may require the
addition of a ªwinter frontº for effective operation of the
cab heating/cooling system. Make certain that a percent-
age of the radiator is exposed for adequate air flow
through the charge air cooler and automatic transmission
oil cooler. The percentage of opening must be increased
with the increasing ambient air temperature and/or
engine load. If the cooling fan can be heard cycling
frequently, increase the size of the opening in the winter
front.
MAINTAINING YOUR VEHICLE 343
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Coolant bottle level check
The coolant reserve system provides a quick visual
method of determining that the coolant level is adequate.
With the engine idling, and warmed to the normal
operating temperature, the level of the coolant on the
coolant bottle should be between the fluid level marks.
Check the coolant level whenever the hood is raised.
The radiator normally remains completely full, so there is
no longer a need to remove the coolant pressure cap
except for checking coolant freeze point or replacement
with new antifreeze coolant.
WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool overheated engine! The coolant is under pres-
sure and severe scalding could result.
Drain, Flush And Refill
At intervals shown on the Maintenance Schedules, the
system should be drained, flushed and refilled. Refer to
your dealer or consult a service manual for proper
procedures.
Adding Coolant
When adding coolant or refilling system, a 50% solution
of ethylene glycol antifreeze coolant in water should be
used. Higher concentrations (not to exceed 65%) are
required if temperatures below -34 ÉF (-37 ÉC) are antici-
pated. Use only high purity water such as distilled or
deionized water when mixing the water/antifreeze solu-
tion. The use of lower quality water will reduce the
amount of corrosion protection in the engine cooling
system. Please note that it is the owner's responsibility to
maintain the proper level of protection against freezing
according to the temperatures occurring in the area
where the vehicle is operated.
344 MAINTAINING YOUR VEHICLE

CAUTION!
Mixing of coolants other than specified (HOAT),
may result in engine damage that may not be cov-
ered under the new vehicle warranty, and decreased
corrosion protection. If a non-HOAT coolant is intro-
duced into the cooling system in an emergency, it
should be replaced with the specified coolant as
soon as possible.
Do not use plain water alone or alcohol base anti-
freeze products. Do not use additional rust inhibi-
tors or antirust products, as they may not be compat-
ible with the radiator coolant and may plug the
radiator.
This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propylene
Glycol based coolants is not recommended.
Disposal Of Used Engine Coolant
Used ethylene glycol based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. Do not store ethylene glycol-based engine
coolant in open containers or allow it to remain in
puddles on the ground. Prevent ingestion by animals and
children. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Coolant Pressure Cap
The coolant pressure cap must be fully tightened to
prevent loss of coolant and to insure that coolant will
return to the radiator from the coolant reserve tank.
346 MAINTAINING YOUR VEHICLE

WARNING!
Never add coolant when the engine is overheated.
Do not loosen or remove the pressure cap to cool an
overheated engine. Heat causes pressure build up in
the cooling system. To prevent scalding or injury, do
not remove the pressure cap while the system is hot
or under pressure.
CAUTION!
Recheck the cooling system to insure total system is
full of coolant.
Fan
Inspection
Check the fan for cracks and bent or broken blades. If any
of these conditions exist, you must replace the fan. Make
sure it is securely mounted.
NOTE:This service procedure must be performed by a
trained service technician. Make arrangements with your
authorized Dodge Truck Dealer for this inspection.
Charge Air Cooler (Inter-Cooler)
The charge air cooler is positioned between the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50 to 100
MAINTAINING YOUR VEHICLE 347
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