trailer Ram 3500 2020 Repair Manual

STARTING AND OPERATING333
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 your 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.
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334STARTING AND OPERATING
* 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. Refer to “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel” for
further information. NOTE:
An aftermarket controller may be available
for use with trailers with air or elec
-
tric-over-hydraulic trailer brake systems. To
determine the type of brakes on your trailer
and the availability of controllers, check with
your trailer manufacturer 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.
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 *Above 10,000 lbs *Under 10,000 lbs *Above 10,000 lbs
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.

20_DJD2_OM_EN_USC_t.book Page 334

STARTING AND OPERATING335
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.
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

1 — Female Pins
2 — Male Pin
3 — Ground
4 — Park
5 — Left Stop/Turn
6 — Right Stop/Turn1 — Battery
2 — Backup Lamps
3 — Right Stop/Turn
4 — Electric Brakes
5 — Ground
6 — Left Stop/Turn
7 — Running Lamps
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336STARTING AND OPERATING
TOWING TIPS
Before setting out on a trip, practice turning,
stopping, and backing up the trailer in an area
located away from heavy traffic.
Automatic Transmission
The DRIVE range can be selected when towing.
The transmission controls include a drive
strategy to avoid frequent shifting when towing.
However, if frequent shifting does occur while in
DRIVE, select TOW/HAUL mode or select a lower
gear range (using the Electronic Range Select
[ERS] shift control).
NOTE:
Using TOW/HAUL mode or selecting a lower
gear range (using the ERS shift control) while
operating the vehicle under heavy loading
conditions will improve performance and
extend transmission life by reducing excessive
shifting and heat build-up. This action will also
provide better engine braking.
Tow/Haul Mode
To reduce potential for automatic transmission
overheating, activate TOW/HAUL mode when
driving in hilly areas, or select a lower gear
range (using the Electronic Range Select [ERS]
shift control) on more severe grades.
Speed Control — If Equipped
Do not use on hilly terrain or with heavy
loads.
When using the Speed Control, if you experi -
ence speed drops greater than 10 mph
(16 km/h), disengage until you can get back
to cruising speed.
Use Speed Control in flat terrain and with
light loads to maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission
overheating, take the following actions: City Driving
In city traffic — while stopped, place the trans
-
mission in NEUTRAL, but do not increase
engine idle speed.
Highway Driving
Reduce speed.
Temporarily turn off air conditioning.
Air Suspension System
To aid in attaching/detaching the trailer from
the vehicle, the air suspension system can be
used. Refer to “Air Suspension System” in
“Starting And Operating” for further
information.
NOTE:
The vehicle must remain in the engine running
position while attaching a trailer for proper
leveling of the air suspension system.

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STARTING AND OPERATING339
RECREATIONAL TOWING (BEHIND MOTORHOME, ETC.)
TOWING THIS VEHICLE BEHIND ANOTHER VEHICLE
NOTE:
When towing your vehicle, always follow
applicable state and provincial laws. Contact
state and provincial Highway Safety offices
for additional details.
Vehicles equipped with air suspension must
be placed in Transport mode before tying
them down (from the body) on a trailer or
flatbed truck. Refer to “Air Suspension – If
Equipped” for more information. If the
vehicle cannot be placed in Transport mode (for example, engine will not run), tie-downs
must be fastened to the axles (not to the
body). Failure to follow these instructions
may cause fault codes to be set and/or
cause loss of proper tie-down tension.RECREATIONAL TOWING — TWO-WHEEL
D
RIVE MODELS
DO NOT flat tow this vehicle. Damage to the
drivetrain will result. Recreational towing (for two-wheel drive
models) is allowed
ONLY if the rear wheels are
OFF the ground. This may be accomplished
using a tow dolly or vehicle trailer. If using a tow
dolly, follow this procedure:
NOTE:
If vehicle is equipped with air suspension,
ensure the vehicle is set to Normal Ride Height.

1. Properly secure the dolly to the tow vehicle, following the dolly manufacturer's
instructions.

Towing Condition Wheels OFF The
Ground Two-Wheel Drive
Models Four-Wheel Drive Models
Flat Tow
NONENOT ALLOWED See InstructionsAutomatic transmission in PARK
Transfer case in NEUTRAL (N)
Tow in forward direction
Dolly Tow Front
NOT ALLOWED NOT ALLOWED
Rear OK NOT ALLOWED
On Trailer ALLOK OK5

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340STARTING AND OPERATING
(Continued)
2. Drive the rear wheels onto the tow dolly.
3. Firmly apply the parking brake. Place automatic transmission in PARK.
4. Properly secure the rear wheels to the dolly, following the dolly manufacturer's
instructions.
5. Turn the ignition OFF and remove the key fob.
6. Install a suitable clamping device, designed for towing, to secure the front wheels in the
straight position.RECREATIONAL TOWING —
F
OUR-WHEEL DRIVE MODELS
NOTE:
Both the manual shift and electronic shift
transfer cases must be shifted into NEUTRAL
(N) for recreational towing. Automatic transmis -
sions must be shifted into PARK for recreational
towing. Refer to the following for the proper
transfer case NEUTRAL (N) shifting procedure
for your vehicle.
CAUTION!
Towing with the rear wheels on the ground
will cause severe transmission damage.
Damage from improper towing is not
covered under the New Vehicle Limited
Warranty.
Do not disconnect the driveshaft because
fluid may leak from the transmission,
causing damage to internal parts.
CAUTION!
DO NOT dolly tow any 4WD vehicle. Towing
with only one set of wheels on the ground
(front or rear) will cause severe transmis -
sion and/or transfer case damage. Tow
with all four wheels either ON the ground, or
OFF the ground (using a vehicle trailer).
Tow only in the forward direction. Towing
this vehicle backwards can cause severe
damage to the transfer case.
Before recreational towing, the transfer
case must be in NEUTRAL. To be certain the
transfer case is fully in NEUTRAL, perform
the procedure outlined under “Shifting Into
NEUTRAL”. Internal transmission damage
will result, if the transfer case is not in
NEUTRAL during towing.
The transmission must be placed in PARK
for recreational towing.
Towing this vehicle in violation of the above
requirements can cause severe transmis -
sion and/or transfer case damage.
Damage from improper towing is not
covered under the New Vehicle Limited
Warranty.
Do not disconnect the rear driveshaft
because fluid will leak from the transfer
case, causing damage to internal parts.
Do not use a bumper-mounted clamp-on
tow bar on your vehicle. The bumper face
bar will be damaged.
CAUTION! (Continued)

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360IN CASE OF EMERGENCY
F2530 Amp Pink –Front Wiper
F26 —–Spare
F27 —–Spare
F28 20 Amp Blue –Trailer Tow Backup Lights – If Equipped
F29 20 Amp Blue –Trailer Tow Parking Lights – If Equipped
F30 30 Amp Pink –Trailer Tow Receptacle / Trailer Tow (Separate E-Brake) /
Trailer Tow
F31 ––Spare
F32 ––Spare
F33 20 Amp Blue –Trans Control Module – If Equipped
F34 30 Amp Pink –Vehicle System Interface Module #2 – If Equipped
F35 30 Amp Pink –Sunroof – If Equipped
F36 30 Amp Pink –Electric Back Light – If Equipped
F37 30 Amp Pink –Diesel Frame / Fuel Heater #2– If Equipped
F38 30 Amp Pink –Integrated Trailer Brake Module – If Equipped
F39 ––Spare
F40 –10 Amp Red Ventilated Seats – If Equipped
F41 –10 Amp Red Active Grille Shutter / Active Air Dam – If Equipped
F42 –20 Amp Yellow Horn
F43 –15 Amp Blue Heated Steering Wheel – If Equipped
F44 –10 Amp Red Diagnostic Port
CavityCartridge Fuse Micro Fuse Description

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IN CASE OF EMERGENCY361
F46 –10 Amp Red Upfitters Relay Coil – If Equipped
F47 ––Spare
F48 ––Spare
F49 –10 Amp Red IP Cluster / CSG
F50 –20 Amp Yellow Air Suspension Control Module – If Equipped
F51 –10 Amp RedIgnition Node Module / Keyless Ignition Node Module,
Radio Frequency Hub Module / Electric Steering Column
Lock - If Equipped
F52 –5 Amp Tan Battery Sensor
F53 –20 Amp Yellow Trailer Tow – Left Turn/Stop Lights - If Equipped
F54 –20 Amp Yellow Non Memory Adjustable Pedals - If Equipped
F55 ––Spare
F56 –10 Amp Red Fuel Vapor Blocker Valve - If Equipped
F57 –20 Amp Yellow TCM / PCM / Solenoid Trans Pressure SW (RFE Trans Only)
– If Equipped
F58 –10 Amp Red Bed Lighting (LED) – If Equipped
F60 –—Spare
F61 –10 Amp Red NH3 Sensor / PM Sensor – If Equipped
F62 –10 Amp Red Air Conditioning Clutch
F63 –20 Amp Yellow Ignition Coils / CAPS
CavityCartridge Fuse Micro Fuse Description
6

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IN CASE OF EMERGENCY363
F81 –20 Amp Yellow Trailer Tow Right Turn / Stop Lights - If Equipped
F82 –10 Amp Red Steering Column Control Module / Cruise Control
F83 ––Spare
F84 –15 Amp Blue ASBM / HVAC / ICS / Rear Heated Seat Switches
F85 –10 Amp Red Airbag Module
F86 –10 Amp Red Airbag Module
F87 –10 Amp RedAir Suspension / ITBM / Steering Column Control Module
/ MOD Gateway CAN-C Trailer TPM
F88 –15 Amp Blue Instrument Panel Cluster
F90/F91 –20 Amp Yellow Power Outlet / Batt
Power Outlet / Acc
F92 ––Spare
F93 ––Spare
F94 –10 Amp RedShift-By-Wire / Transfer Case Switch / Module TPM Trailer
/ Module Gateway Can-C Trailer TPM
F95 –10 Amp RedRearview Camera / Park Assist / CHMSL Camera / Blind
Spot Sensor / Surround View Camera
F96 –10 Amp Red Trailer Camera – If Equipped
F97 –20 Amp Yellow Front Heated Seat Passenger – If Equipped
F98 –20 Amp Yellow Front Heated Seat Driver – If Equipped
F99 –10 Amp Red HVAC / In-Car Temperature Sensor / CSG MOD
CavityCartridge Fuse Micro Fuse Description
6

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IN CASE OF EMERGENCY381
(Continued)
TOWING A DISABLED VEHICLE
This section describes procedures for towing a
disabled vehicle using a commercial towing
service.
If the transmission and drivetrain are operable,
disabled vehicles may also be towed as
described under “Recreational Towing” in the
“Starting And Operating” section. NOTE:
Vehicles equipped with the Air Suspension
System must be placed in Transport mode,
before tying them down (from the body) on a
trailer or flatbed truck. If the vehicle cannot be
placed in Transport mode (for example, engine
will not run), tie-downs must be fastened to the
axles (not to the body). Failure to follow these
instructions may cause fault codes to be set
and/or cause loss of proper tie-down tension.
Refer to “Air Suspension System — If Equipped”
in “Starting And Operating” for more informa
-
tion.
CAUTION!
Racing the engine or spinning the wheels
may lead to transmission overheating and
failure. Allow the engine to idle with the
transmission in NEUTRAL for at least one
minute after every five rocking-motion
cycles. This will minimize overheating and
reduce the risk of transmission failure
during prolonged efforts to free a stuck
vehicle.
When “rocking” a stuck vehicle by shifting
between DRIVE and REVERSE, do not spin
the wheels faster than 15 mph (24 km/h), or drivetrain damage may result.
Revving the engine or spinning the wheels
too fast may lead to transmission over -
heating and failure. It can also damage the
tires. Do not spin the wheels above 30 mph
(48 km/h) while in gear (no transmission
shifting occurring).
CAUTION! (Continued)
6

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