2021 RAM PROMASTER trailer light

152SAFETY
ESC Partial Off
This mode is entered by momentarily pushing
the ESC OFF button.
When in the “Partial Off” mode, the TCS portion
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 the “Partial Off” mode,
ESC will operate without engine torque
management. This mode is intended to be used
if the vehicle is in deep snow, sand or gravel
conditions and more wheel spin than ESC would
normally allow is required to gain traction.
To turn ESC on again, momentarily push the
ESC OFF button. This will restore the normal
“ESC On” mode of operation. NOTE:
To improve the vehicle's traction when driving
with snow chains, or starting off in deep snow,
sand or gravel, it may be desirable to switch to
the “Partial Off” mode by pushing the ESC OFF
button. Once the situation requiring ESC to be
switched to the “Partial Off” mode is overcome,
turn ESC back on by momentarily pushing the
ESC OFF button. This may be done while the
vehicle is in motion.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 turned to the ON 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.
The ESC Activation/Malfunction Indicator Light
starts to flash as soon as the tires lose traction
and the ESC system becomes active. The ESC
Activation/Malfunction Indicator Light also
flashes when TCS is active. If the ESC
Activation/Malfunction Indicator Light begins to
flash during acceleration, ease up on the
accelerator and apply as little throttle as
possible. Be sure to adapt your speed and
driving to the prevailing road conditions.
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.

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SAFETY153
The ESC OFF Indicator Light indicates
that the Electronic Stability Control
(ESC) is in a reduced mode.
NOTE:
The ESC Activation/Malfunction Indicator
Light and the ESC OFF Indicator Light come
on momentarily each time the ignition switch
is placed in the ON position.
Each time the ignition is placed in the ON
position, the ESC system will be on even if it
was turned off previously.
The ESC system will make buzzing or clicking
sounds when it is active. This is normal; the
sounds will stop when ESC becomes inactive
following the maneuver that caused the ESC
activation.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver
when starting a vehicle from a stop on a hill.
HSA will maintain the level of brake pressure
the driver applied for a short period of time after
the driver takes their foot off of the brake pedal.
If the driver does not apply the throttle during
this short period of time, the system will release
brake pressure and the vehicle will roll down the
hill. The system will release brake pressure in
proportion to the amount of throttle applied as
the vehicle starts to move in the intended
direction of travel.
HSA Activation Criteria
The following criteria must be met in order for
HSA to activate:
The vehicle must be stopped.
The vehicle must be on a 6% (approximate)
grade or greater hill.

Gear selection matches vehicle uphill direction
(i.e., vehicle facing uphill is in forward gear;
vehicle backing uphill is in REVERSE gear).

HSA will work in REVERSE and all forward gears
when the activation criteria have been met. The
system will not activate if the vehicle is placed
in NEUTRAL or PARK.
WARNING!
There may be situations on minor hills with a
loaded vehicle, or while pulling a trailer, when
the system will not activate and slight rolling
may occur. This could cause a collision with
another vehicle or object. Always remember
the driver is responsible for braking the
vehicle.
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154SAFETY
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
brake pressure is applied to the slipping
wheel(s) and engine power is reduced, 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. This feature remains
active even if the ESC is in the “Partial Off”
mode.
The ESC Activation/Malfunction Indicator Light
(in the instrument cluster) will start to flash as
soon as the tires lose traction and the wheels
begin to spin. This indicates that the TCS is
active. If the indicator light flashes during
acceleration, ease up on the accelerator and
apply as little throttle as possible. Be sure to
adapt your speed and driving to the prevailing
road conditions, and do not switch off the ESC
or TCS.
Trailer Sway Control (TSC) — If Equipped
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate actions to attempt to stop the sway.
The system may reduce engine power and apply
the brake of the appropriate wheel(s) to
counteract the sway of the trailer.
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.
WARNING!
The TCS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded.
The TCS cannot prevent collisions,
including those resulting from excessive
speed in turns, or hydroplaning.
The capabilities of a TCS-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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SAFETY155
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 78.
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” mode.AUXILIARY DRIVING SYSTEMS
BLIND SPOT MONITORING (BS M) — IF
E
QUIPPED
The BSM system 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. The BSM detection zone covers approximately
one lane width on both sides of the vehicle 12 ft
(3.8 m). The zone length starts at the outside
rear view mirror and extends approximately
10 ft (3 m) beyond the rear fascia/bumper of
the vehicle. The BSM system monitors the
detection zones on both sides of the vehicle
when the vehicle speed reaches approximately
6 mph (10 km/h) or higher and will alert the
driver of vehicles in these areas.
NOTE:
The BSM system DOES NOT alert the driver
about rapidly approaching vehicles that are
outside the detection zones.
The Blind Spot Monitoring (BSM) system may
experience dropouts (blinking on and off) of
the side mirror Warning Indicator lamps
when a motorcycle or any small object
remains at the side of the vehicle for
extended periods of time (more than a couple
of seconds).
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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211
SERVICING AND MAINTENANCE
SCHEDULED SERVICING
Your vehicle is equipped with an automatic oil
change indicator system. The oil change
indicator system will remind you that it is time to
take your vehicle in for scheduled maintenance.

Based on engine operation conditions, the oil
change indicator message will illuminate in the
instrument cluster. This means that service is
required for your vehicle. Operating conditions
such as frequent short-trips, trailer tow, and
extremely hot or cold ambient temperatures will
influence when the “Oil Change Required”
message is displayed. Severe Operating
Conditions can cause the change oil message to
illuminate as early as 3,500 miles (5,600 km)
since last reset. Have the vehicle serviced as
soon as possible, within the next 500 miles
(805 km).
An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change. If a scheduled oil change
is performed by someone other than an
authorized dealer, the message can be reset by
referring to the steps described under
Instrument Cluster Display Ú
page 45.
NOTE:
Under no circumstances should oil change
intervals exceed 10,000 miles (16,000 km),
12 months or 350 hours of engine run time,
whichever comes first. The 350 hours of engine
run or idle time is generally only a concern for
fleet customers. Severe Duty All Models

Vehicles that are operated in a dusty and off-road
environment, or predominately at idle or very low
engine RPM are known as Severe Duty vehicles.
It is recommended that you change the engine oil
at 4,000 miles (6,500 km) or 350 hours of
engine run time.

Once A Month Or Before A Long Trip:
Check engine oil level
Check windshield washer fluid level
Check the tire pressures and look for unusual
wear or damage. Rotate at the first sign of
irregular wear, even if it occurs before the oil
indicator system turns on
Check the fluid levels of the coolant reservoir,
brake master cylinder, and power steering
and fill as needed
Check function of all interior and exterior
lights
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278 H
Hazard Driving Through Flowing, Rising, OrShallow Standing Water
.......................... 86Hazard Warning Flashers.............................. 190Head Restraints............................................... 20HeadlightsCleaning.................................................... 260High Beam.................................................. 26High Beam/Low Beam Select Switch.......... 26Passing........................................................ 26Switch......................................................... 26Heated Mirrors................................................ 25Heated Seats................................................... 19Heater, Engine Block....................................... 58High Beam/Low Beam Select (Dimmer)
Switch.............................................................. 26Hill Start Assist.............................................. 153HitchesTrailer Towing.............................................. 80Hood Prop........................................................ 40Hood Release.................................................. 40
I
Ignition............................................................ 12Key....................................................... 10, 12Switch......................................................... 12Ignition Key Removal....................................... 12Illuminated Entry............................................. 30
Immobilizer (Sentry Key).................................. 12Inside Rearview Mirror..................................... 23Instrument Cluster.................................... 42, 54Display......................................................... 44Instrument Panel Lens Cleaning................... 262Interior And Instrument Lights......................... 28Interior Appearance Care.............................. 261Interior Lights................................................... 28Intermittent Wipers (Delay Wipers).................. 30iPod/USB/MP3 Control.................................... 37
J
Jack Location................................................ 190Jack Operation.............................................. 190Jacking And Tire Changing............................ 190Jacking And Tire Changing Instructions........ 191Jump Starting............................................... 203
K
Key FobProgramming Additional Key Fobs
............... 11Key Fob Battery Service
(Remote Keyless Entry).................................... 11Key Fob Programming
(Remote Keyless Entry).................................... 11Key-In Reminder.............................................. 12Keys................................................................. 10Replacement............................................... 11Sentry (Immobilizer).................................... 12
L
Lane Change Assist..........................................27Lap/Shoulder Belts....................................... 166Latches......................................................... 188Hood............................................................40Lead Free Gasoline....................................... 265Leaks, Fluid................................................... 189Life Of Tires................................................... 251Light Bulbs........................................... 188, 235Lights............................................................ 188Air Bag...................................... 48, 173, 187Brake Assist Warning................................ 152Brake Warning.............................................49Bulb Replacement.................................... 235Cruise..........................................................54Daytime Running.........................................26Dimmer Switch, Headlight...........................26Electronic Stability Program(ESP) Indicator........................................ 49, 152Exterior.............................................. 26, 188Hazard Warning Flasher........................... 190Headlights...................................................26High Beam...................................................26Illuminated Entry.........................................30Interior.........................................................28Malfunction Indicator (Check Engine)..........52Park......................................................26, 54Passing........................................................26

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