2016 Ram 2500 ECU

If you must use the accessories (wipers, defrosters, etc.)
while being towed, the ignition must be in the ON/RUN
position, not the ACC position.
If the key fob is unavailable or the vehicle’s battery is
discharged, refer to ”Manual Park Release” or “Gear
Selector Override” in this section for instructions on
shifting the automatic transmission out of PARK for
towing.
CAUTION!
•Do not use sling type equipment when towing.
Vehicle damage may occur.
• When securing the vehicle to a flat bed truck, do
not attach to front or rear suspension components.
Damage to your vehicle may result from improper
towing.
Two-Wheel Drive Models
The manufacturer recommends towing your vehicle with
all four wheels OFFthe ground using a flatbed.
If flatbed equipment is not available, and the transmis-
sion is operable, this vehicle may be towed (with rear
wheels on the ground) under the following conditions:
• The transmission must be in NEUTRAL.
• The towing speed must not exceed 30 mph (48 km/h).
• The towing distance must not exceed 15 miles (24 km)
for 6-speed transmission, or 30 miles (48 km) for
8-speed transmission.
If the transmission is not operable, or the vehicle must be
towed faster than 30 mph (48 km/h) or farther than 15
miles (24 km) for 6-speed transmission, or 30 miles
(48 km) for 8-speed transmission, tow with the rear
wheels OFFthe ground. Acceptable methods are to tow
the vehicle on a flatbed, or with the front wheels raised
784 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLE
CONTENTS
ENGINE COMPARTMENT — 3.6L ..........790
 ENGINE COMPARTMENT — 5.7L ..........791
 ENGINE COMPARTMENT — 6.4L ..........792
 ONBOARD DIAGNOSTIC SYSTEM (OBD II) . . .793
▫ Onboard Diagnostic System (OBD II)
Cybersecurity ....................... .793
▫ Loose Fuel Filler Cap Message ............794
 EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS ......................... .795
 REPLACEMENT PARTS ..................796 
DEALER SERVICE ..................... .797
 MAINTENANCE PROCEDURES ...........797
▫ Engine Oil ......................... .798
▫ Engine Oil Filter ..................... .802
▫ Engine Air Cleaner Filter ................802
▫ Accessory Drive Belt Inspection ...........806
▫ Maintenance-Free Battery ...............808
▫ Air Conditioner Maintenance .............809
▫ Front Driveshaft Lubrication — 2500/3500
(Four-Wheel Drive Models Only) ..........810
7

ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light (MIL).” It
will also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible.
CAUTION!
•Prolonged driving with the MIL on could cause
further damage to the emission control system. It
could also affect fuel economy and driveability.
The vehicle must be serviced before any emissions
tests can be performed.
• If the MIL is flashing, while the engine is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Onboard Diagnostic System (OBD II)
Cybersecurity
Your vehicle is required to have an Onboard Diagnostic
system (OBD II) and a connection port to allow access to
information related to the performance of your emissions
controls. Authorized service technicians may need to
7
MAINTAINING YOUR VEHICLE 793

access this information to assist with the diagnosis and
service of your vehicle and emissions system.
WARNING!
•ONLY an authorized service technician should con-
nect equipment to the OBD II connection port in
order to diagnose or service your vehicle.
• If unauthorized equipment is connected to the
OBD II connection port, such as a driver-behavior
tracking device, it may:
• Be possible that vehicle systems, including
safety related systems, could be impaired or a
loss of vehicle control could occur that may result
in an accident involving serious injury or death.
• Access, or allow others to access, information
stored in your vehicle systems, including per-
sonal information. For further information, refer to “Privacy Practices — If
Equipped With Uconnect 8.4 Radio” and “Uconnect
CyberSecurity” in “All About Uconnect Access” in your
Owner ’s Manual Radio Supplement and “Cybersecurity”
in “Understanding Your Instrument Panel” in your Own-
er ’s Manual on the DVD.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines
that the fuel filler cap is loose, improperly
installed, or damaged, a loose gascap indicator
will display in the EVIC/DID telltale display
area. Refer to “Electronic Vehicle Information Center
(EVIC)” or “Driver Information Display (DID)” in “Un-
derstanding Your Instrument Panel” for further informa-
tion. Tighten the fuel filler cap properly and push the
794 MAINTAINING YOUR VEHICLE

WARNING!(Continued)
•To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that has
been in a tightly closed container. Keep the master
cylinder reservoir cap secured at all times. Brake
fluid in a open container absorbs moisture from the
air resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or pro-
longed braking, resulting in sudden brake failure.
This could result in a collision.
• Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing
the brake fluid to catch fire. Brake fluid can also
damage painted and vinyl surfaces, care should be
taken to avoid its contact with these surfaces.
(Continued)
WARNING! (Continued)
•Do not allow petroleum based fluid to contaminate
the brake fluid. Brake seal components could be
damaged, causing partial or complete brake failure.
This could result in a collision.
Rear Axle And 4x4 Front Driving Axle Fluid Level
For normal service, periodic fluid level checks are not
required. When the vehicle is serviced for other reasons
the exterior surfaces of the axle assembly should be
inspected. If gear oil leakage is suspected inspect the
fluid level. Refer to “Fluids, Lubricants, And Genuine
Parts” in “Maintaining Your Vehicle” for further informa-
tion. This inspection should be made with the vehicle in
a level position.
7
MAINTAINING YOUR VEHICLE 827

BULB REPLACEMENT
NOTE:Lens fogging can occur under certain atmo-
spheric conditions. This will usually clear as atmospheric
conditions change to allow the condensation to change
back into a vapor. Turning the lamps on will usually
accelerate the clearing process.
Base Quad / Premium Bi-Halogen: Low Beam
Headlamp, High Beam Headlamp, Front Park And
Turn — If Equipped
1. Open the hood.
2. Disconnect and isolate the negative battery cable.
3. Remove the six plastic push-in fasteners that secure the upper radiator seal to the grille support and both
fender ledges.
4. Remove the two plastic push-in rivets that secure the upper radiator seal to the radiator. 5. Remove the upper radiator seal from the vehicle.
6. Remove the two headlamp assembly attachment
screws.
Headlamp Assembly Attachment Screw Locations
854 MAINTAINING YOUR VEHICLE

Adding Engine Coolant (Antifreeze)............820
Adding Fuel ............................ .684
Additives, Fuel .......................... .679
Adjust Down .............................. .148
Forward ......................... .148, 150
Rearward ........................ .148, 150
Up ................................ .148
Adjustable Pedals ........................ .189
AirBag.................................71 Advance Front Air Bag ....................73
Air Bag Operation .......................74
Air Bag Warning Light ....................82
Enhanced Accident Response ................81
Event Data Recorder (EDR) .................84
FrontAirBag...........................71
If A Deployment Occurs ...................80
Knee Impact Bolsters .....................75
Maintaining Your Air Bag System ............83Side Air Bags
...........................75
Transporting Pets .......................117
Air Bag Deployment ........................71
Air Bag Light ..................... .82, 120, 297
Air Bag Maintenance .......................83
Air Cleaner, Engine (Engine Air Cleaner Filter) . . . .802
Air Conditioner Maintenance .................809
Air Conditioning ..................... .421, 426
Air Conditioning Controls ................421, 426
Air Conditioning, Operating Tips ...........441, 443
Air Conditioning Refrigerant ..............809, 810
Air Conditioning System ..........421, 426, 439, 809
Air Pressure, Tires .....................649, 660
Air Suspension ....................... .545, 558
Alarm, Panic .............................29
Alarm (Security Alarm) ..................22, 300
Alarm System (Security Alarm) ................22
Alterations/Modifications, Vehicle ...............7
Antifreeze (Engine Coolant) ...............819, 864
896 INDEX

Lane Change Assist....................... .182
Lap/Shoulder Belts .........................56
Latches ............................... .122
Lead Free Gasoline ....................... .675
Leaks, Fluid ............................ .122
Life Of Tires ............................ .658
Light Bulbs ......................... .122, 852
Lights ............................. .122, 170
AirBag ........................82, 120, 297
Automatic Headlights ....................171
Brake Assist Warning ....................630
Brake Warning ........................ .298
Bulb Replacement ...................... .854
Cap Top Clearance ..................... .860
Cargo .............................. .180
Center Mounted Stop ....................858
Courtesy/Reading ................178, 180, 215
Cruise ........................... .327, 329
Daytime Running ...................... .173Engine Temperature Warning
...............300
Exterior ............................. .122
Fog ......................... .176, 317, 856
Four-Wheel Drive Indicator ................526
Hazard Warning Flasher ..................727
Headlights ........................... .171
High Beam ........................... .182
High Beam/Low Beam Select ...............182
Hill Descent Control Indicator ..............632
Illuminated Entry ........................24
Interior ....................177, 178, 180, 215
Low Fuel ............................ .314
Malfunction Indicator (Check Engine) .........307
Park ............................ .325, 327
Passing ............................. .182
Seat Belt Reminder ..................... .296
Security Alarm ........................ .300
Service .......................... .852,

854
Side Marker .......................... .86310
INDEX 905