2021 RAM CHASSIS CAB wiring

STARTING AND OPERATING135
Do Not Operate The Engine With Low Oil Pressure
When the engine is at normal operating temperature, the minimum oil pressures required are:
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.
DIESEL PARTICULATE FILTER (DPF)
M
ANUAL REGENERATION - IF EQUIPPED
On equipped Chassis Cabs, a manual
regeneration can be enable through the
instrument cluster. The manual regeneration
will allow the DPF to complete a regeneration,
lowering the soot level without having to drive
the vehicle. The vehicle must be in PARK to
access this feature, and the fuel level must be
over 12.5% full. A message displaying the time
left on the regeneration will appear on the
instrument cluster, and the instrument cluster
will display the soot level Ú page 90.
ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms the engine, and
permits quicker starts in cold weather. Connect
the cord to a standard 110-115 Volt AC
electrical outlet with a grounded, three-wire
extension cord.
Gas Engine Only
The engine block heater cord is routed through
the grille by the right front tow hook.
It includes a removable cap that is secured by a
tethered strap. It also has a c-clip that is used
for storage when not in use for the Winter
months. During Winter months, remove the
heater cord wiring assembly from itself on the
c-clip.
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.4

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208STARTING AND OPERATING
If a fault is detected in the trailer wiring or the
Integrated Trailer Brake Module (ITBM), the
“Trailer Brake Status Indicator Light” will flash.
GAIN Adjustment Buttons (+/-)
Pushing these buttons will adjust the brake
control power output to the trailer brakes in
0.5 increments. The GAIN setting can be
increased to a maximum of 10 or decreased
to a minimum of 0 (no trailer braking).
GAIN
The GAIN setting is used to set the trailer brake
control for the specific towing condition and
should be changed as towing conditions
change. Changes to towing conditions include
trailer load, vehicle load, road conditions and
weather.
Adjusting GAIN
NOTE:
This should only be performed in a traffic-free
environment at speeds of approximately
20–25 mph (30–40 km/h).
1. Make sure the trailer brakes are in good
working condition, functioning normally
and properly adjusted. See a trailer dealer
if necessary.

2. Hook up the trailer and make the electrical connections according to the trailer
manufacturer's instructions.
3. When a trailer with electric/EOH brakes is plugged in, the trailer connected message
should appear in the instrument cluster
display (if the connection is not recognized
by the ITBM, braking functions will not be
available), the GAIN setting will illuminate
and the correct type of trailer must be
selected from the instrument cluster display
options.
4. Push the UP or DOWN button on the steering wheel until “TRAILER TOW”
appears on the screen.
5. Push the RIGHT arrow on the steering wheel to enter “TRAILER TOW”. 6. Push the UP or DOWN buttons until the
Trailer Brake Type appears on the screen.
7. Push the RIGHT arrow and then push the UP or DOWN buttons until the proper Trailer
Brake Type appears on the screen.
8. In a traffic-free environment, tow the trailer on a dry, level surface at a speed of
20–25 mph (30–40 km/h) and squeeze
the manual brake control lever completely.
9. If the trailer wheels lockup (indicated by squealing tires), reduce the GAIN setting; if
the trailer wheels turn freely, increase the
GAIN setting.
Repeat steps 8 and 9 until the GAIN setting is at
a point just below trailer wheel lockup. If towing
a heavier trailer, trailer wheel lockup may not be
attainable even with the maximum GAIN setting
of 10.

21_DPF_OM_EN_USC_t.book Page 208

STARTING AND OPERATING209
* The suggested selection depends and
may change depending on the customer
preferences for braking performance. Condition
of the trailer brakes, driving and road state may
also affect the selection.
Display Messages
The trailer brake control interacts with the
instrument cluster display. Display messages,
along with a single chime, will be displayed
when a malfunction is determined in the trailer
connection, trailer brake control, or on the
trailer Úpage 90. NOTE:
An aftermarket controller may be available
for use with trailers with air or EOH trailer
brake systems. To determine the type of
brakes on your trailer and the availability of
controllers, check with your trailer manufac
-
turer or dealer.
Removal of the ITBM will cause errors and it
may cause damage to the electrical system
and electronic modules of the vehicle. See an
authorized dealer if an aftermarket module is
to be installed.
Towing Requirements — Trailer Lights And
Wiring
Whenever you pull a trailer, regardless of the
trailer size, stoplights and turn signals on the
trailer are required for motoring safety.
The Trailer Tow Package may include a four- and
seven-pin wiring harness. Use a factory
approved trailer harness and connector.
NOTE:
Do not cut or splice wiring into the vehicle’s
wiring harness.
The electrical connections are all complete to
the vehicle but you must mate the harness
to a trailer connector. Refer to the following
illustrations.
Light Electric Heavy Electric Light EOHHeavy EOH
Type of Trailer Brakes Electric Trailer Brakes Electric Trailer Brakes Electric over Hydraulic
Trailer BrakesElectric over Hydraulic
Trailer Brakes
Load
*Under 10,000 lbs (4,536 kg) *Above 10,000 lbs (4,536 kg) *Under 10,000 lbs (4,536 kg) *Above 10,000 lbs (4,536 kg)

WARNING!

Connecting a trailer that is not compatible with
the ITBM system may result in reduced or
complete loss of trailer braking. There may be a
increase in stopping distance or trailer instability
which could result in personal injury.

CAUTION!
Connecting a trailer that is not compatible
with the ITBM system may result in reduced
or complete loss of trailer braking. There may
be a increase in stopping distance or trailer
instability which could result in damage to
your vehicle, trailer, or other property.4

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210STARTING AND OPERATING
NOTE:
Disconnect trailer wiring connector from the
vehicle before launching a boat (or any other
device plugged into vehicle’s electrical
connect) into water.
Be sure to reconnect once clear from water
area.

Four-Pin Connector Seven-Pin Connector

Trailer Light Check
This feature will run the trailer lights through a
sequence to check the trailer light function. It is
available in the instrument cluster under the
Trailer Tow menu Ú page 94. When activated the feature will enable all of the
exterior lights sequentially for up to five minutes
allowing time to walk around and verify
functionality. The following exterior lights will
remain on for the entirety of the sequence:Park/Running Lamps
Side Marker Lamps (if equipped)
License Lamp
Signature Lamp (if equipped)
Low Beams
Fog Lamps (if equipped)
Daytime Running Lamps
During this time the following lights will
sequence, each activating for three seconds:

1. Brake and CHMSL (third brake light)

2. Left turn signal
3. Right turn signal
4. Reverse Lamps
5. High Beam
1 — Ground
2 — Park
3 — Left Stop/Turn
4 — Right Stop/Turn
1 — Backup Lamps
2 — Running Lamps
3 — Left Stop/Turn
4 — Ground
5 — Battery
6 — Right Stop/Turn
7 — Electric Brakes

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302SAFETY
How To Engage The Automatic Locking Mode

1. Buckle the combination lap and shoulder belt.

2. Grab the shoulder portion and pull
downward until the entire seat belt is
extracted.
3. Allow the seat belt to retract. As the seat belt retracts, you will hear a clicking sound.
This indicates the seat belt is now in the
Automatic Locking Mode. How To Disengage The Automatic Locking Mode
Unbuckle the combination lap/shoulder belt
and allow it to retract completely to disengage
the Automatic Locking Mode and activate the
vehicle sensitive (emergency) locking mode.
SUPPLEMENTAL RESTRAINT SYSTEMS
(SRS)
Some of the safety features described in this
section may be standard equipment on some
models, or may be optional equipment on
others. If you are not sure, ask an authorized
dealer.

The air bag system must be ready to protect
you in a collision. The Occupant Restraint
Controller (ORC) monitors the internal circuits
and interconnecting wiring associated with the
electrical Air Bag System Components. Your
vehicle may be equipped with the following Air
Bag System Components:

Air Bag System Components
Occupant Restraint Controller (ORC)
Air Bag Warning Light
Steering Wheel and Column
Instrument Panel
Knee Impact Bolsters
Driver and Front Passenger Air Bags
WARNING!
Never place a rear-facing child restraint in
front of an air bag. A deploying passenger
front air bag can cause death or serious
injury to a child 12 years or younger,
including a child in a rear-facing child
restraint.
Never install a rear-facing child restraint in
the front seat of a vehicle. Only use a
rear-facing child restraint in the rear seat.
If the vehicle does not have a rear seat, do
not transport a rear-facing child restraint in
that vehicle.
WARNING!

The seat belt assembly must be replaced if
the switchable Automatic Locking Retractor
(ALR) feature or any other seat belt function
is not working properly when checked
according to the procedures in the Service
Manual.
Failure to replace the seat belt assembly
could increase the risk of injury in collisions.

Do not use the Automatic Locking Mode to
restrain occupants who are wearing the
seat belt or children who are using booster
seats. The locked mode is only used to
install rear-facing or forward-facing child
restraints that have a harness for
restraining the child.

21_DPF_OM_EN_USC_t.book Page 302

SAFETY309
Air Bag System Components
NOTE:
The Occupant Restraint Controller (ORC) moni -
tors the internal circuits and interconnecting
wiring associated with electrical Air Bag System
Components listed below:
Occupant Restraint Controller (ORC)
Air Bag Warning Light
Steering Wheel and Column
Instrument Panel
Knee Impact Bolsters
Driver and Front Passenger Air Bags
Seat Belt Buckle Switch
Supplemental Side Air Bags — If Equipped
Front and Side Impact Sensors — If Equipped
Seat Belt Pretensioners — If Equipped
If A Deployment Occurs
The front air bags are designed to deflate
immediately after deployment. NOTE:
Front and/or side air bags will not deploy in all
collisions. This does not mean something is
wrong with the air bag system.
If you do have a collision which deploys the air
bags, any or all of the following may occur:
The air bag material may sometimes cause
abrasions and/or skin reddening to the occu
-
pants as the air bags deploy and unfold. The
abrasions are similar to friction rope burns or
those you might get sliding along a carpet or
gymnasium floor. They are not caused by
contact with chemicals. They are not perma -
nent and normally heal quickly. However, if
you haven’t healed significantly within a few
days, or if you have any blistering, see your
doctor immediately.
As the air bags deflate, you may see some
smoke-like particles. The particles are a
normal by-product of the process that gener -
ates the non-toxic gas used for air bag infla -
tion. These airborne particles may irritate the
skin, eyes, nose, or throat. If you have skin or
eye irritation, rinse the area with cool water.
For nose or throat irritation, move to fresh air. If the irritation continues, see your doctor. If
these particles settle on your clothing, follow
the garment manufacturer’s instructions for
cleaning.
Do not drive your vehicle after the air bags
have deployed. If you are involved in another
collision, the air bags will not be in place to
protect you.
NOTE:
Air bag covers may not be obvious in the inte -
rior trim, but they will open during air bag
deployment.
After any collision, the vehicle should be
taken to an authorized dealer immediately.
WARNING!

Deployed air bags and seat belt pretensioners
cannot protect you in another collision. Have
the air bags, seat belt pretensioners, and the
seat belt retractor assemblies replaced by an
authorized dealer immediately. Also, have the
Occupant Restraint Controller System serviced
as well.

6

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SAFETY311
(Continued)
Maintaining Your Air Bag System Event Data Recorder (EDR)
This vehicle is equipped with an event data
recorder (EDR). The main purpose of an EDR is
to record, in certain crash or near crash-like
situations, such as an air bag deployment or
hitting a road obstacle, data that will assist
in understanding how a vehicle’s systems
performed. The EDR is designed to record data
related to vehicle dynamics and safety systems for a short period of time, typically 30 seconds
or less. The EDR in this vehicle is designed to
record such data as:
How various systems in your vehicle were
operating;
Whether or not the driver and passenger
safety belts were buckled/fastened;
How far (if at all) the driver was depressing
the accelerator and/or brake pedal; and,
How fast the vehicle was traveling.
These data can help provide a better
understanding of the circumstances in which
crashes and injuries occur.
NOTE:
EDR data are recorded by your vehicle only if a
non-trivial crash situation occurs; no data are
recorded by the EDR under normal driving
conditions and no personal data (e.g., name,
gender, age, and crash location) are recorded.
However, other parties, such as law enforce -
ment, could combine the EDR data with the type
of personally identifying data routinely acquired
during a crash investigation.
WARNING!
Modifications to any part of the air bag
system could cause it to fail when you need
it. You could be injured if the air bag system
is not there to protect you. Do not modify
the components or wiring, including adding
any kind of badges or stickers to the
steering wheel hub trim cover or the upper
passenger side of the instrument panel.
Do not modify the front fascia/bumper,
vehicle body structure, or add aftermarket
side steps or running boards.
It is dangerous to try to repair any part of
the air bag system yourself. Be sure to tell
anyone who works on your vehicle that it
has an air bag system.

Do not attempt to modify any part of your air
bag system. The air bag may inflate acciden -
tally or may not function properly if modifica -
tions are made. Take your vehicle to an
authorized dealer for any air bag system
service. If your seat, including your trim cover
and cushion, needs to be serviced in any way
(including removal or loosening/tightening
of seat attachment bolts), take the vehicle to
an authorized dealer. Only manufacturer
approved seat accessories may be used. If it
is necessary to modify the air bag system for
persons with disabilities, contact an autho -
rized dealer.

WARNING! (Continued)
6

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SERVICING AND MAINTENANCE375
Some conditions can be caused by a faulty
component such as a belt pulley. Belt pulleys
should be carefully inspected for damage and
proper alignment.
Belt replacement on some models requires the
use of special tools, we recommend having your
vehicle serviced at an authorized dealer.
DRAINING FUEL/WATER SEPARATOR
F
ILTER
There are two fuel filter assemblies. One is
located on the driver's side of the engine.
The best access to this water drain valve is from
under the hood. The second one is on the under
body, located in front of the rear axle above the
drive shaft on pick-up models. The Chassis Cab
models second filter location is on the frame
behind the front axle. The best access to this
water drain valve is from under the vehicle. If water is detected in the water separator while
the engine is running, or while the ignition
switch is in the ON position, the “Water In Fuel
Indicator Light” will illuminate and an audible
chime will be heard five times. At this point you
should stop the engine and drain the water from
both of the filters.
If the “Water In Fuel Indicator Light” comes on
and a single chime is heard while you are
driving, or with the ignition switch in the ON
position, there may be a problem with your
water separator wiring or sensor. See an
authorized dealer for service.
Upon proper draining of the water from both
fuel filters, the “Water In Fuel Indicator Light”
will remain illuminated for approximately
10 seconds. If the water was drained while
the engine was running, the “Water In Fuel
Indicator Light” may remain on for
approximately three minutes.NOTE:
Care should be taken in disposing of used fluids
from your vehicle. Used fluids, indiscriminately
discarded, can present a problem to the envi
-
ronment. Contact an authorized dealer, service
station, or government agency for advice on
recycling programs and for where used fluids
and filters can be properly disposed of in your
area.

Drain the fuel/water separator filters when the
“Water In Fuel Indicator Light” is ON. Within
10 minutes of vehicle shutdown, turn the engine
mounted filter drain valve (located on the side of
the filter assembly) counterclockwise a quarter
turn, and turn the under body mounted filter
drain valve (located on the bottom of the filter
assembly) counterclockwise 1 full turn. Then turn
the ignition switch to the ON position, and allow
any accumulated water to drain. Leave the drain
valve open until all water and contaminants have
been removed. When clean fuel is visible, close
the drain valve following these guidelines:

1. Rotate the drain clockwise to close until you feel resistance from the internal seal.

2. Continue turning the drain half of a turn to properly compress the seal.
CAUTION!
Do not drain the fuel/water separator filter
when the engine is running.
Diesel fuel will damage blacktop paving
surfaces. Drain the filter into an appro-
priate container.
CAUTION!
If the “Water In Fuel Indicator Light” remains
on, DO NOT START the engine before you
drain water from the fuel filters to avoid
engine damage.
8

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