trailer RAM 1500 2021 Service Manual

226STARTING AND OPERATING

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 118.
When activated the feature will enable all of the
exterior lights sequentially for up to two minutes
for 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
This light check sequence will continue for a
total of two minutes. The sequence will only activate if the following
conditions are met:
Vehicle is equipped with the Trailer Tow
Package
Vehicle is in PARK
Vehicle is not in motion
Ignition in ACC or RUN
Remote start is inactive
Brakes are not applied
Left turn signal is not applied
Right turn signal not applied
Hazard switch is not applied
The sequence will cancel if any of the following
conditions occur:
Brakes are applied
Vehicle is shifted from PARK
Vehicle is no longer stationary
Left turn signal activated from stalk
Right turn signal is activated from stalk
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 OPERATING227
Hazard switch is activated
Any button on the key fob is pushed
Ignition button is pushed
High Beam stalk position is changed
Sequence is canceled in the instrument
cluster
TOWING TIPS
Before towing, 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 (ERS) shift control) on more
severe grades.
Cruise Control — If Equipped
Do not use on hilly terrain or with heavy
loads.
When using the Cruise Control, if you experi
-
ence speed drops greater than 10 mph
(16 km/h), disengage until you can get back
to cruising speed.
Use Cruise Control in flat terrain and with
light loads to maximize fuel efficiency.
Air Suspension System
To aid in attaching/detaching the trailer from
the vehicle, the air suspension system can be
used Ú page 165. 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 an
authorized dealer, installer or snowplow manu
-
facturer for this information. There are unique
electrical systems that must be connected to
properly ensure operator safety and prevent
overloading vehicle systems.
4

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230STARTING AND OPERATING
RECREATIONAL TOWING (BEHIND MOTORHOME)
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 Active-Level Four
Corner Air Suspension must be placed in
Transport mode before tying them down
(from the body) on a trailer or flatbed truck
Úpage 165. 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.

2. Drive the rear wheels onto the tow dolly.
3. Apply the parking brake. Place the transmission in PARK.
Towing Condition Wheels OFF The Ground Two-Wheel Drive Models Four-Wheel Drive Models
Flat Tow NONENOT ALLOWED See InstructionsTransmission in PARK
Transfer case in NEUTRAL (N)
Tow in forward direction
Dolly Tow Front
NOT ALLOWED NOT ALLOWED
Rear OKNOT ALLOWED
On Trailer ALLOKOK

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STARTING AND OPERATING231
(Continued)
4. Properly secure the rear wheels to the dolly, following the dolly manufacturer's
instructions.
5. Turn the ignition OFF.
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:
The transfer case must be shifted into N
(Neutral) for recreational towing. The transmis -
sion must be shifted into PARK for recreational
towing. Refer to the following for the proper
transfer case N (Neutral) 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.
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 N (Neutral). To be certain
the transfer case is fully in N (Neutral),
perform the procedure outlined under
“Shifting Into N (Neutral)”. Internal trans -
mission damage will result, if the transfer
case is not in N (Neutral) during towing.
The transmission must be in PARK for
recreational towing.
Ensure that the Electric Park Brake is
released, and remains released, while
being towed.
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)
4

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MULTIMEDIA243
LaneSense Warning This setting will change the distance at which the steering wheel will
provide lane departure feedback. The available settings are “Early”,
“Medium”, and “Late”.
LaneSense Strength
This setting will change the strength of the steering wheel feedback
during a lane departure. The available setting are “Low”, “Medium”, and
“High”.
ParkSense This setting will change the type of ParkSense alert when a close object is
detected. The “Sound Only” setting will provide an audible chime when
an object is detected. The “Sound and Display” setting will provide both
an audible chime and a visual display when an object is detected.
Front ParkSense Volume This setting adjusts the volume of the Front ParkSense system. The
available settings are “Low”, “Medium”, and “High”.
Rear ParkSense Volume This setting adjusts the volume of the Rear ParkSense system. The
available settings are “Low”, “Medium”, and “High”.
Rear ParkSense Braking Assist This setting will turned the Rear ParkSense Braking Assist on or off.
Blind Spot Alert This setting will change the type of alert provided when an object is
detected in a vehicle’s blind spot. The “Off” setting will turn off Blind Spot
Alert. The “Lights” setting will activate the Blind Spot Alert lights on the
outside mirrors. The “Lights & Chime” setting will activate both the lights
on the outside mirrors and an audible chime.
Trailer Length For Blind Spot Alert This setting will auto detect the length of an attached trailer. The “Auto”
setting will have the system automatically set the trailer length. The
“Max” setting will always set the length to the maximum 39.5 ft (12 m).
Hill Start Assist This setting will turn the Hill Start Assist system on or off.
Setting NameDescription
5

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MULTIMEDIA251
Trailer Brake/Trailer
When the Trailer Brake/Trailer button is pressed on the touchscreen, the system will display settings related to trailer towing.
Audio
When the Audio button is pressed on the touchscreen, the system displays options related to the vehicle’s sound system. These settings can change
the audio location within the vehicle, adjust the bass or treble levels, and auto-play settings from an audio device or smartphone.
Setting Name Description
Trailer Select Select from Trailer 1, Trailer 2, Trailer 3, and Trailer 4. These trailer
designations can be used to save different trailer settings.
Trailer Brake Type This setting will set the system to a specific trailer type. The available
options are “Light Electrics”, “Heavy Electric”, “Light
Electric-Over-Hydraulic”, and “Heavy Electric-Over-Hydraulic”.
Trailer Name This setting will personalize the trailer name depending on the type of
trailer you are hauling. Select the trailer name from the following list:
trailer, boat, car, cargo, dump, equipment, flatbed, gooseneck, horse,
livestock, motorcycle, snowmobile, travel, utility, and 5th wheel.
Setting Name
Description
Balance/Fade This setting will adjust audio levels from specific speakers in the front/
back and left/right of the vehicle. The Speaker icon can be moved to set
audio location.
Equalizer This setting will adjust the “Bass”, “Mid”, and “Treble” ranges of the
audio.
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SAFETY311
Anti-Lock Brake System (ABS) Warning
Light
The yellow ABS Warning Light will turn on when
the ignition is placed in the ON/RUN mode and
may stay on for as long as four seconds.
If the ABS Warning Light remains on or comes
on while driving, it indicates that the anti-lock
portion of the brake system is not functioning
and that service is required. However, the
conventional brake system will continue to
operate normally if the ABS Warning Light is on.
If the ABS Warning Light is on, the brake system
should be serviced as soon as possible to
restore the benefits of anti-lock brakes. If the
ABS Warning Light does not come on when the
ignition is placed in the ON/RUN mode, have
the light repaired as soon as possible.
ELECTRONIC BRAKE CONTROL (EBC)
S
YSTEM
Your vehicle is equipped with an advanced
Electronic Brake Control (EBC) system. This
system includes Anti-Lock Brake System (ABS),
Brake Assist System (BAS), Electronic Brake
Force Distribution (EBD), Electronic Roll
Mitigation (ERM), Electronic Stability Control
(ESC), Hill Start Assist (HSA), and Traction Control System (TCS). These systems work
together to enhance both vehicle stability and
control in various driving conditions.
Your vehicle may also be equipped with Trailer
Sway Control (TSC) and Hill Descent Control
(HDC).
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s
braking capability during emergency braking
maneuvers. The system detects an emergency
braking situation by sensing the rate and
amount of brake application, and then applies
optimum pressure to the brakes. This can help
reduce braking distances. The BAS
complements the Anti-Lock Brake System
(ABS). Applying the brakes very quickly results
in the best BAS assistance. To receive the
benefit of the system, you must apply
continuous braking pressure during the
stopping sequence (do not “pump” the brakes).
Do not reduce brake pedal pressure unless
braking is no longer desired. Once the brake
pedal is released, the BAS is deactivated.
Brake System Warning Light
The red Brake System Warning Light will turn on
when the ignition is placed in the ON/RUN
mode and may stay on for as long as four
seconds.
If the Brake System Warning Light remains on or
comes on while driving, it indicates that the
brake system is not functioning properly and
that immediate service is required. If the Brake
System Warning Light does not come on when
the ignition is placed in the ON/RUN mode,
have the light repaired as soon as possible.
WARNING!
The Brake Assist System (BAS) cannot
prevent the natural laws of physics from
acting on the vehicle, nor can it increase the
traction afforded by prevailing road
conditions. BAS cannot prevent collisions,
including those resulting from excessive
speed in turns, driving on very slippery
surfaces, or hydroplaning. The capabilities of
a BAS-equipped vehicle must never be
exploited in a reckless or dangerous manner,
which could jeopardize the user's safety or
the safety of others.
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314SAFETY
(Continued)
Full Off — If Equipped
This mode is intended for off-highway or
off-road use only and should not be used on any
public roadways. In this mode, TCS and ESC
features are turned off. To enter the “Full Off”
mode, push and hold the ESC OFF switch for five
seconds while the vehicle is stopped with the
engine running. After five seconds, a chime will
sound, the ESC OFF Indicator Light will
illuminate, and the “ESC OFF” message will
display in the instrument cluster. To turn ESC on
again, momentarily push the ESC OFF switch.NOTE:
System may switch from ESC “Full Off” to
“Partial Off” mode when vehicle exceeds a
predetermined speed. When the vehicle speed
slows below the predetermined speed the
system will return to ESC “Full Off”.
ESC modes may also be affected by drive
modes (if equipped).
ESC Activation/Malfunction Indicator Light
And ESC OFF Indicator Light
The ESC Activation/Malfunction
Indicator Light in the instrument
cluster will come on when the ignition
is placed in the ON/RUN mode. It
should go out with the engine running. If the
ESC Activation/Malfunction Indicator Light
comes on continuously with the engine running,
a malfunction has been detected in the ESC
system. If this light remains on after several
ignition cycles, and the vehicle has been driven
several miles (kilometers) at speeds greater
than 30 mph (48 km/h), see an authorized
dealer as soon as possible to have the problem
diagnosed and corrected.
WARNING!
When in “Partial Off” mode, the TCS func -
tionality of ESC, (except for the limited slip
feature described in the TCS section), has
been disabled and the “ESC OFF Indicator
Light” will be illuminated. When in “Partial
Off” mode, the engine power reduction
feature of TCS is disabled, and the
enhanced vehicle stability offered by the
ESC system is reduced.
Trailer Sway Control (TSC) is disabled when
the ESC system is in the “Partial Off” mode.
WARNING!
In the ESC “Full Off” mode, the engine
torque reduction and stability features are
disabled. Therefore, enhanced vehicle
stability offered by the ESC system is
unavailable. In an emergency evasive
maneuver, the ESC system will not engage
to assist in maintaining stability. ESC “Full
Off” mode is intended for off-highway or
off-road use only.
The Electronic Stability Control (ESC)
cannot prevent the natural laws of physics
from acting on the vehicle, nor can it
increase the traction afforded by prevailing
road conditions. ESC cannot prevent all
accidents, including those resulting from
excessive speed in turns, driving on very
slippery surfaces, or hydroplaning. ESC also
cannot prevent collisions.
WARNING! (Continued)

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SAFETY317
Hill Start Assist (HSA)
HSA is designed to mitigate roll back from a
complete stop while on an incline. If the driver
releases the brake while stopped on an incline,
HSA will continue to hold the brake pressure for
a short period. If the driver does not apply the
throttle before this time expires, the system will
release brake pressure and the vehicle will roll
down the hill as normal.
The following conditions must be met in order
for HSA to activate:
The feature must be enabled.
The vehicle must be stopped.
The parking brake must be off.
The driver door must be closed.
The vehicle must be on a sufficient grade.
The gear selection must match vehicle uphill
direction (i.e., vehicle facing uphill is in
forward gear; vehicle backing uphill is in
REVERSE gear).
HSA will work in REVERSE gear and all
forward gears. The system will not activate if
the transmission is in PARK or NEUTRAL.
Disabling And Enabling HSA
This feature can be turned on or turned off. To
change the current setting, proceed as follows:
If disabling HSA using Uconnect Settings
Úpage 237.
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.WARNING!
There may be situations where the Hill Start
Assist (HSA) will not activate and slight rolling
may occur, such as on minor hills or with a
loaded vehicle, or while pulling a trailer. HSA
is not a substitute for active driving
involvement. It is always the driver’s
responsibility to be attentive to distance to
other vehicles, people, and objects, and most
importantly brake operation to ensure safe
operation of the vehicle under all road
conditions. Your complete attention is always
required while driving to maintain safe control
of your vehicle. Failure to follow these
warnings can result in a collision or serious
personal injury.
WARNING!
If you use a trailer brake controller with your
trailer, the trailer brakes may be activated
and deactivated with the brake switch. If
so, there may not be enough brake pres -
sure to hold both the vehicle and the trailer
on a hill when the brake pedal is released.
In order to avoid rolling down an incline
while resuming acceleration, manually acti -
vate the trailer brake or apply more vehicle
brake pressure prior to releasing the brake
pedal.
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the trans -
mission in PARK.
Failure to follow these warnings can result
in a collision or serious personal injury.
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318SAFETY
Ready Alert Braking (RAB)
RAB may reduce the time required to reach full
braking during emergency braking situations. It
anticipates when an emergency braking
situation may occur by monitoring how fast the
throttle is released by the driver. The Electronic
Brake Control System will prepare the brake
system for a panic stop.
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
the TCS may apply brake pressure to the
spinning wheel(s) and/or reduce engine power
to provide enhanced acceleration and stability.
A feature of the TCS, Brake Limited Differential
(BLD), functions similarly to a limited slip
differential and controls the wheel spin across a
driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will
apply the brake of the spinning wheel. This will
allow more engine torque to be applied to the
wheel that is not spinning. BLD may remain
enabled even if TCS and Electronic Stability
Control (ESC) are in reduced modes.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate actions to attempt to stop the sway.
NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda -
tions Ú page 214.
When TSC is functioning, the ESC Activation/
Malfunction Indicator Light will flash, the engine
power may be reduced and you may feel the
brakes being applied to individual wheels to
attempt to stop the trailer from swaying. TSC is
disabled when the ESC system is in the “Partial
Off” or “Full Off” modes.AUXILIARY DRIVING SYSTEMS
BLIND SPOT MONITORING (BSM) — IF
E
QUIPPED
BSM uses two radar sensors, located inside the
taillights, to detect highway licensable vehicles
(automobiles, trucks, motorcycles, etc.) that
enter the blind spot zones from the rear/front/
side of the vehicle.

Rear Detection Zones

When the vehicle is started, the BSM Warning
Light will momentarily illuminate in both outside
rearview mirrors to let the driver know that the
system is operational. The BSM system sensors
operate when the vehicle is in any forward gear
or REVERSE and enters standby mode when the
vehicle is in PARK.
WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and
adjust the trailer load to eliminate trailer
sway.

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