
•5 MPH Max Speed in 150 mi Service DEF System See
Dealer — This message will display if the DEF system
has not been serviced after the “Service DEF System –
See Dealer” message is displayed. This message will
continuously display until the mileage counter reaches
zero, and will be accompanied by a periodic chime.
The message will continue to countdown until it
reaches zero unless the vehicle is serviced. We recom-
mend you drive to your nearest authorized dealer and
have your vehicle serviced immediately.
NOTE: Under some circumstances this mileage counter
may start with a value of less than 150 miles (241 km). For
example, if recurring faults are detected in a time interval
of less than 40 hours, the counter may restart at the value
where it stopped when a previous fault was temporarily
remedied, or at a minimum of 50 miles (80 km). •
5 MPH Max Speed on Restart, Long Idle or Refuel
Service DEF See Dealer — This message will continu-
ously display when the mileage counter reaches zero,
and will be accompanied by a periodic chime.
• The vehicle will only be capable of a maximum speed
of 5 MPH upon the first of the following conditions to
occur:
• If the vehicle is shutoff and restarted.
• If the vehicle is idled for an extended period of time,
approximately one hour or greater.
• If the system detects that the level of fuel in the tank
has increased.
• 5 MPH Max Speed Service DEF System See Dealer —
This message will continuously display, and will be
accompanied by a periodic chime. Although the ve-
hicle can be started and placed in gear, the vehicle will
4
UNDERSTANDING YOUR INSTRUMENT PANEL 251

only operate at a maximum speed of 5 MPH. Your
vehicle will require towing, see your authorized dealer
for service.
• Engine Will Not Restart Service DEF System See
Dealer — This message will display if DEF system
issue detected is not serviced during the allowed
period. Your engine will not restart unless your vehicle
is serviced by your authorized dealer. This message
will be displayed when under 1 mile until engine will
not start and each time the vehicle is started, and will
be continuously displayed. The message will be ac-
companied by a single chime. Your Malfunction Indi-
cator Light will be continuously illumined. We highly
recommend you drive to your nearest authorized
dealer if the message appears while engine is running.
NOTE: When this message is displayed, the engine can
still be started. However, the vehicle will only operate at
a maximum speed of 5 MPH.RAM Active Air System
Your vehicle is equipped with an advanced Ram Active
Air system that provides enhanced performance, espe-
cially when towing under demanding hot or high alti-
tude conditions. If the DID displays the message “Active
Airbox Service Required See Dealer”, vehicle perfor-
mance may be reduced until service is performed by an
authorized RAM dealer.
Fuel Filter Life Reset
The cluster will display the “Service Fuel Filter” message
when the fuel filter maintenance life is less than 5%. To
check the remaining fuel filter life, go to the “Fuel Filter
Life” screen in the “Vehicle Info” menu. When this
message appears, dealers should replace both frame
mounted and engine mounted fuel filters.
NOTE: Use the steering wheel EVIC controls for the
following procedure(s)
252 UNDERSTANDING YOUR INSTRUMENT PANEL

Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating temperature, the
minimum oil pressures required are:
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage.
Do Not Operate The Engine With Failed Parts
All engine failures give some warning before the parts
fail. Be on the alert for changes in performance, sounds,
and visual evidence that the engine requires service.
Some important clues are:•
Engine misfiring or vibrating severely.
• Sudden loss of power.
• Unusual engine noises.
• Fuel, oil or coolant leaks.
• Sudden change, outside the normal operating range, in
the engine operating temperature.
• Excessive smoke.
• Oil pressure drop.
ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the heater
cord to a ground-fault interrupter protected 110–115 Volt
AC electrical outlet with a grounded, three-wire exten-
sion cord.
280 STARTING AND OPERATING
![Ram 2500 2016 Diesel Supplement cold temperatures (-16°F [-27°C] or below), operation
may briefly be limited to first and direct gears only. On
trucks with AS69RC transmission, fifth and sixth gears
may be inhibited briefly on col Ram 2500 2016 Diesel Supplement cold temperatures (-16°F [-27°C] or below), operation
may briefly be limited to first and direct gears only. On
trucks with AS69RC transmission, fifth and sixth gears
may be inhibited briefly on col](/manual-img/34/12564/w960_12564-294.png)
cold temperatures (-16°F [-27°C] or below), operation
may briefly be limited to first and direct gears only. On
trucks with AS69RC transmission, fifth and sixth gears
may be inhibited briefly on cold starts below 41°F (5°C),
and during very cold temperatures (-4°F [-20°C] or
below), operation may briefly be limited to third gear
only. During this condition, the ability of the vehicle to
accelerate under heavily loaded conditions may be re-
duced. In all cases, normal operation will resume once
the transmission temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in fourth gear (for 68RFE transmission) or third gear (for
AS69RC transmission) regardless of which forward gear
is selected. If an AS69RC-equipped truck enters LimpHome Mode at highway speeds, it will initially engage
fifth gear, until the vehicle slows to a speed where third
gear can be engaged. PARK, REVERSE, and NEUTRAL
will continue to operate. The Malfunction Indicator Light
(MIL) may be illuminated. Limp Home Mode allows the
vehicle to be driven to an authorized dealer for service
without damaging the transmission.
In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the OFF position.
4. Wait approximately 10 seconds.
5
STARTING AND OPERATING 293

5. Restart the engine.
6. Shift into the desired gear range. If the problem is nolonger detected, the transmission will return to normal
operation.
NOTE: Even if the transmission can be reset, we recom-
mend that you visit your authorized dealer at your
earliest possible convenience. Your authorized dealer has
diagnostic equipment to determine if the problem could
recur.
If the transmission cannot be reset, authorized dealer
service is required.Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control allows the
driver to limit the highest available gear when the
transmission is in DRIVE. For example, if you set the
transmission gear limit to 4 (fourth gear), the transmis-
sion will not shift above fourth gear, but will shift
through the lower gears normally.
You can switch between DRIVE and ERS mode at any
vehicle speed. When the shift lever is in the DRIVE
position, the transmission will operate automatically,
shifting between all available gears. Tapping the ERS (-)
switch will activate ERS mode, display the current gear in
the instrument cluster, and set that gear as the top
available gear. Once in ERS mode, tapping the ERS (-) or
(+) switch will change the top available gear.
294 STARTING AND OPERATING

WARNING!
In case of engine runaway due to flammable fumes
from fuel spills or turbocharger oil leaks being
sucked into the engine, do the following to help
avoid personal injury and/or vehicle damage:
1. Turn the ignition switch to the OFF position.
2. Using a CO2 or dry chemical type fire extinguisher,
direct the spray from the fire extinguisher into the
grille on the passenger side so that the spray enters
the engine air intake.
The inlet for the engine air intake is located behind
the passenger side headlamp and receives air
through the grille.
FUEL REQUIREMENTS
Use good quality diesel fuel from a reputable supplier in
your vehicle. Federal law requires that you must fuel this
vehicle with Ultra Low Sulfur Highway Diesel fuel (15
ppm Sulfur maximum) and prohibits the use of Low
Sulfur Highway Diesel fuel (500 ppm Sulfur maximum)
to avoid damage to the emissions control system.
For most year-round service, No. 2 diesel fuel meeting
ASTM (formerly known as the American Society for
Testing and Materials) specification D-975 Grade S15 will
provide good performance. If the vehicle is exposed to
extreme cold (below 20°F or -7°C), or is required to
operate at colder-than-normal conditions for prolonged
periods, use climatized No. 2 diesel fuel or dilute the No.
2 diesel fuel with 50% No. 1 diesel fuel. This will provide
better protection from fuel gelling or wax-plugging of the
fuel filters.
5
STARTING AND OPERATING 307

NOTE:
•If you accidentally fill the fuel tank with gasoline on
your diesel vehicle, Do not start the vehicle. If you
restart your vehicle you risk damaging the engine and
fuel system. Please call your local dealer for service.
• A maximum blend of 5% biodiesel meeting ASTM
specification D-975 may be used with your Cummins
diesel engine. (Chassis Cab models not configured
with B20 capability.)
• A maximum blend of 20% biodiesel meeting ASTM
specification D-7467 may be used with your Cummins
diesel engine. (Pickup models and Chassis Cab models
configured with B20 Capability.)
• In addition, commercially available fuel additives are
not necessary for the proper operation of your Cum-
mins diesel engine. However, if seasonably adjusted
fuel is not available and you are operating below 20°F (-6°C), MOPAR Premium Diesel Fuel Treatment (or
equivalent) may be beneficial to avoid fuel gelling.
• No. 1 Ultra Low Sulfur diesel fuel should only be used
where extended arctic conditions (-10°F or -23°C) exist.
Bio-Diesel Fuel Requirements
Chassis Cab Models
A maximum blend of 5% biodiesel meeting ASTM speci-
fication D975 may be used with your Cummins diesel
engine. If operation with Biodiesel blends greater than
5% but not greater than 20% (B6-B20) is desired, the truck
must first be reconfigured by an authorized Ram dealer
and the provisions in the following section must be
adhered to.5
STARTING AND OPERATING 309

approved ASTM standards, if stored properly, provides
for protection against fuel oxidation for up to six months.
Fuel Water Separation — Must Use MOPAR/
Cummins Approved Fuel Filter Elements
You must use MOPAR/Cummins approved fuel filter
elements in both your engine mounted filter and frame
mounted filter.
Biodiesel fuel has a natural affinity to water and water
accelerates microbial growth. Your MOPAR/Cummins
filtration system is designed to provide adequate fuel
water separation capabilities.
Bio-Diesel Fuel Properties — Low Ambient
Temperatures
Biodiesel fuel may gel or solidify at low ambient tem-
peratures, which may pose problems for both storage and
operation. Precautions can be necessary at low ambienttemperatures, such as storing the fuel in a heated build-
ing or a heated storage tank, or using cold temperature
additives.
Fuel In Oil Dilution — Must Adhere To Required
Oil Change Interval
Fuel dilution of lubricating oil has been observed with
the use of Biodiesel fuel. Fuel in oil must not exceed 5%.
To ensure this limit is met your oil change interval must
be maintained to the following schedule:
•
Ram PickUp 2500/3500 Only — 15,000 Miles*
• Ram 3500/4500/5500 Chassis Cab — 12,500 Miles*
(*unless otherwise notified with a oil service message)
5
STARTING AND OPERATING 311