trailer Ram 2500 2020 Repair Manual

324STARTING AND OPERATING
(Continued)
Towing Requirements — Tires
Do not attempt to tow a trailer while using a
compact spare tire.
Do not drive more than 50 mph (80 km/h) when towing while using a full size spare tire.
Proper tire inflation pressures are essential
to the safe and satisfactory operation of your
vehicle. Refer to “Tires” in “Servicing And
Maintenance” for proper tire inflation proce -
dures.
Check the trailer tires for proper tire inflation
pressures before trailer usage.
Check for signs of tire wear or visible tire
damage before towing a trailer. Refer to
“Tires” in “Servicing And Maintenance” for
the proper inspection procedure.
When replacing tires, refer to “Tires” in
“Servicing And Maintenance” for the proper
tire replacement procedures. Replacing tires
with a higher load carrying capacity will not
increase the vehicle's GVWR and GAWR
limits.
Towing Requirements — Trailer Brakes
Do not interconnect the hydraulic brake
system or vacuum system of your vehicle
with that of the trailer. This could cause inad -
equate braking and possible personal injury.
An electronically actuated trailer brake
controller is required when towing a trailer
with electronically actuated brakes. When
towing a trailer equipped with a hydraulic
surge actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers
over 1,000 lbs (453 kg) and required for
trailers in excess of 2,000 lbs (907 kg).
When hauling cargo or towing a trailer, do
not overload your vehicle or trailer. Over -
loading can cause a loss of control, poor
performance or damage to brakes, axle,
engine, transmission, steering, suspension,
chassis structure or tires.
Safety chains must always be used
between your vehicle and trailer. Always
connect the chains to the hook retainers of
the vehicle hitch. Cross the chains under
the trailer tongue and allow enough slack
for turning corners.
Vehicles with trailers should not be parked
on a grade. When parking, apply the
parking brake on the tow vehicle. Put the
tow vehicle transmission in PARK. For
four-wheel drive vehicles, make sure the
transfer case is not in NEUTRAL. Always,
block or "chock" the trailer wheels.
GCWR must not be exceeded.
WARNING! (Continued)
Total weight must be distributed between
the tow vehicle and the trailer such that the
following four ratings are not exceeded :
GVWR
GTW
GAWR
Tongue weight rating for the trailer
hitch utilized.
WARNING! (Continued)

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STARTING AND OPERATING325
Integrated Trailer Brake Module — If
Equipped
Your vehicle may have an Integrated Trailer
Brake Module (ITBM) for Electric and Electric
Over Hydraulic (EOH) trailer brakes. NOTE:
This module has been designed and verified
with electric trailer brakes and new electric over
hydraulic systems. Some previous EOH systems
may not be compatible with ITBM.

Integrated Trailer Brake Module (ITBM)

The user interface consists of the following:
Manual Brake Control Lever
Slide the manual brake control lever to the left
to activate power to the trailer's electric brakes
independent of the tow vehicle's brakes. If the
manual brake control lever is activated while
the brake is also applied, the greater of the two inputs determines the power sent to the trailer
brakes.
The trailer and the vehicle’s stop lamps will
come on when braking normally with the vehicle
brake pedal. Only the trailer stop lamps will
come on when the manual brake control lever is
applied.
Trailer Brake Status Indicator Light
This light indicates the trailer electrical connec
-
tion status.
If no electrical connection is detected after the
ignition is turned on, pushing the GAIN adjust -
ment button or sliding the manual brake control
lever will display the GAIN setting for 10
seconds and the “Trailer Brake Status Indicator
Light” will not be displayed.
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).
WARNING!
Do not connect trailer brakes to your
vehicle's hydraulic brake lines. It can over -
load your brake system and cause it to fail.
You might not have brakes when you need
them and could have an accident.
Towing any trailer will increase your stop -
ping distance. When towing, you should
allow for additional space between your
vehicle and the vehicle in front of you.
Failure to do so could result in an accident.
CAUTION!
If the trailer weighs more than 1,000 lbs
(453 kg) loaded, it should have its own
brakes and they should be of adequate
capacity. Failure to do this could lead to
accelerated brake lining wear, higher brake
pedal effort, and longer stopping distances.1 — GAIN Adjustment Button
2 — GAIN Adjustment Button
3 — Manual Brake Control Lever
5

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326STARTING AND OPERATING
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 manu -
facturer'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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STARTING AND OPERATING327
* The suggested selection depends and may
change depending on the customer prefer -
ences 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
your 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 illustra -
tions.
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.
5

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328STARTING 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

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.1 — Female Pins
2 — Male Pin
3 — Ground
4 — Park
5 — Left Stop/Turn
6 — Right Stop/Turn
1 — Battery
2 — Backup Lamps
3 — Right Stop/Turn
4 — Electric Brakes
5 — Ground
6 — Left Stop/Turn
7 — Running Lamps

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STARTING AND OPERATING329
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 informa
-
tion.
NOTE:
The vehicle must remain in the engine running
position while attaching a trailer for proper
leveling of the air suspension system.
SNOWPLOW
Snowplow Prep Packages are available as a
factory installed option. These packages
include components necessary to equip your
vehicle with a snowplow.
NOTE:
Before installation of a snowplow it is highly
recommended that the owner/installer obtain
and follow the recommendations contained
within the current Body Builders Guide. See
your authorized dealer, installer or snowplow
manufacturer for this information. There are
unique electrical systems that must be
connected to properly ensure operator safety
and prevent overloading vehicle systems.
Before Plowing
Check the hydraulic system for leaks and
proper fluid level.
Check the mounting bolts and nuts for proper
tightness.
Check the runners and cutting edge for
excessive wear. The cutting edge should be
¼ to ½ inches (6 cm to 1.2 cm) above ground
in snow plowing position.
Check that snowplow lighting is connected
and functioning properly.
WARNING!
Attaching a snowplow to this vehicle could
adversely affect performance of the airbag
system in a collision. Do not expect that the
airbag will perform as described earlier in this
manual.
CAUTION!
The “Lamp Out” indicator could illuminate if
exterior lamps are not properly installed.
5

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STARTING AND OPERATING331
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 Drive
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 instruc -
tions.

2. Drive the rear wheels onto the tow dolly.
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 OK
5

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332STARTING AND OPERATING
(Continued)
3. Firmly apply the parking brake. Place auto-
matic transmission in PARK.
4. Properly secure the rear wheels to the dolly, following the dolly manufacturer's instruc -
tions.
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 — Four-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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IN CASE OF EMERGENCY355
F0940 Amp Green (SSV &
Cummins Diesel) –
Aux Relay Output / Diesel Fuel Heater – If Equipped
F09 30 Amp Pink –Brake Vacuum Pump – If Equipped (HD Only)
F10 40 Amp Green –Body Controller / Exterior Lighting #2
F11 30 Amp Pink –PWR - Trailer Tow Electric Brake Batt Feed – If Equipped
(DS 1500 Only)
F11 40 Amp Green –Brake System Module (ECU and Valves) (HD Only)
F12 40 Amp Green –Body Controller #3
F13 40 Amp Green –Blower Motor
F14 40 Amp Green –Body Controller #4 / Exterior Lighting
F15 30 Amp Pink
40 Amp Green –
–Power Side Steps – If Equipped (HD Only)
Extra Fuse - SSV Only
F16 30 Amp Pink –Smart-Bar Module – If Equipped (HD Only)
F17 30 Amp Pink –Winch Control Module – If Equipped (HD Only)
F19 20 Amp Blue (DS 1500 LD
Diesel)
30 Amp Pink (Cummins Diesel) –
SCR – If Equipped
F20 30 Amp Pink –Passenger Door Module
F21 30 Amp Pink –Drive Train Control Module
F22 20 Amp Blue –Engine Control Module GPEC / Heavy Duty / Other – If
Equipped
Cavity
Cartridge Fuse Micro Fuse Description
6

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356IN CASE OF EMERGENCY
F2225 Amp White (Cummins
Diesel) –
PCM – If Equipped
F23 30 Amp Pink –CBC Feed # 1
F24 30 Amp Pink –Driver Door Module
F25 30 Amp Pink –Front Wiper
F26 30 Amp Pink –Antilock Brakes / Stability Control Module / Valves – If
Equipped (DS 1500 Only)
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 (BUX)
F31 30 Amp Pink –Diesel Heater Control – If Equipped (DS 1500 LD Diesel)
F31 20 Amp Blue –Aux App SSV Only - If Equipped
F32 ––Aux Feed, Special Services Vehicle-If Equipped (DS 1500
Only)
F33 20 Amp Blue –Trans Control Module – If Equipped (HD Only)
Aux Feed, SSV Only (DS 1500 Only)
F34 30 Amp Pink –Vehicle System Interface Module #2 – If Equipped (HD
Only)
SSV (DS 1500 Only)
F35 30 Amp Pink –Sunroof – If Equipped
F36 30 Amp Pink –Electric Back Light – If Equipped
Cavity Cartridge Fuse Micro Fuse Description

20_DJD2_OM_EN_USC_t.book Page 356