2021 RAM 1500 light

STARTING AND OPERATING177
TO MANUALLY TURN ON THE STOP
S
TART SYSTEM
Push the Stop/Start OFF switch (located on the
switch bank). The light on the switch will turn
off.
SYSTEM MALFUNCTION
If there is a malfunction in the Stop/Start
system, the system will not shut down the
engine. A “SERVICE STOP/START SYSTEM”
message will appear in the instrument cluster
display Ú page 126.
The system will need to be checked by an
authorized dealer.
CRUISE CONTROL SYSTEMS — IF EQUIPPED
Your vehicle may be equipped with the Cruise
Control system, or the Adaptive Cruise Control
(ACC) system:
Cruise Control for cruising at a constant
preset speed.
Adaptive Cruise Control (ACC) for maintaining
a set distance between you and the vehicle
ahead using Fixed Speed Cruise Control to
automatically adjust the preset speed. NOTE:
In vehicles equipped with ACC, if an ACC
distance is not set, Fixed Speed Cruise Control
will not detect vehicles directly ahead of you.
Always be aware of the mode selected.
CRUISE CONTROL — IF EQUIPPED
When engaged, the Cruise Control takes over
accelerator operations at speeds greater than
20 mph (32 km/h).
The Cruise Control buttons are located on the
right side of the steering wheel.

Cruise Control Buttons
NOTE:
In order to ensure proper operation, the Cruise
Control system has been designed to shut down
if multiple Cruise Control functions are operated
at the same time. If this occurs, the Cruise
Control system can be reactivated by pushing
the Cruise Control on/off button and resetting
the desired vehicle set speed.
To Activate
Push the on/off button to activate the Cruise
Control. The cruise indicator light in the
instrument cluster display will illuminate. To
turn the system off, push the on/off button a 1 — CANC/Cancel
2 — SET (+)/Accel
3 — On/Off
4 — RES/Resume
5 — SET (-)/Decel
WARNING!
Cruise Control can be dangerous where the
system cannot maintain a constant speed.
Your vehicle could go too fast for the
conditions, and you could lose control and
have an accident. Do not use Cruise Control
in heavy traffic or on roads that are winding,
icy, snow-covered or slippery.
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178STARTING AND OPERATING
second time. The cruise indicator light will turn
off. The system should be turned off when not in
use.
To Set A Desired Speed
Turn the Cruise Control on.
When the vehicle has reached the desired
speed, push the SET (+) or SET (-) button and
release. Release the accelerator and the
vehicle will operate at the selected speed.
NOTE:
The vehicle should be traveling at a steady
speed and on level ground before pushing the
SET (+) or SET (-) button.
To Vary The Speed Setting
To Increase Or Decrease The Set Speed
When the Cruise Control is set, you can increase
speed by pushing the SET (+) button, or
decrease speed by pushing the SET (-) button.
U.S. Speed (mph)
Pushing the SET (+), or SET (-) button once
will result in a 1 mph speed adjustment. Each
subsequent tap of the button results in an
adjustment of 1 mph.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
Metric Speed (km/h)
Pushing the SET (+), or SET (-) button once
will result in a 1 km/h speed adjustment.
Each subsequent tap of the button results in
an adjustment of 1 km/h.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
To Accelerate For Passing
While the Cruise Control is set, press the
accelerator to pass as you would normally.
When the pedal is released, the vehicle will
return to the set speed.
Using Cruise Control On Hills
The transmission may downshift on hills to
maintain the vehicle set speed.
NOTE:
The Cruise Control system maintains speed up
and down hills. A slight speed change on
moderate hills is normal.
On steep hills, a greater speed loss or gain may
occur so it may be preferable to drive without
Cruise Control.
WARNING!
Leaving the Cruise Control system on when
not in use is dangerous. You could
accidentally set the system or cause it to go
faster than you want. You could lose control
and have an accident. Always ensure the
system is off when you are not using it.
WARNING!
Cruise Control can be dangerous where the
system cannot maintain a constant speed.
Your vehicle could go too fast for the
conditions, and you could lose control and
have an accident. Do not use Cruise Control
in heavy traffic or on roads that are winding,
icy, snow-covered or slippery.

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STARTING AND OPERATING179
(Continued)
To Resume Speed
To resume a previously set speed, push the RES
button and release. Resume can be used at any
speed above 20 mph (32 km/h).
To Deactivate
A tap on the brake pedal, pushing the CANC
(cancel) button, or normal brake pressure while
slowing the vehicle will deactivate the Cruise
Control system without erasing the set speed
from memory.
The following conditions will also deactivate the
Cruise Control system without erasing the set
speed from memory:
Vehicle parking brake is applied
Stability event occurs
Gear selector is moved out of DRIVE
Engine overspeed occurs
Pushing the on/off button or placing the ignition
in the OFF position, erases the set speed from
memory.
ADAPTIVE CRUISE CONTROL (ACC) — IF
E
QUIPPED
Adaptive Cruise Control (ACC) increases the
driving convenience provided by Cruise Control
while traveling on highways and major
roadways. However, it is not a safety system
and not designed to prevent collisions. The
Cruise Control function performs differently
Ú page 177.
ACC will allow you to keep Cruise Control
engaged in light to moderate traffic conditions
without the constant need to reset your speed.
ACC utilizes a radar sensor and a forward facing
camera designed to detect a vehicle directly
ahead of you to maintain a set speed.
NOTE:
If the ACC sensor detects a vehicle ahead,
ACC will apply limited braking or acceleration
(not to exceed the original set speed) auto -
matically to maintain a preset following
distance, while matching the speed of the
vehicle ahead.
Any chassis/suspension or tire size modifica -
tions to the vehicle will affect the perfor -
mance of the Adaptive Cruise Control and
Forward Collision Warning system.
Fixed Speed Cruise Control alone (an ACC
distance not set) will not detect vehicles
directly ahead of you. Always be aware of the
mode selected.
WARNING!
Adaptive Cruise Control (ACC) is a conve -
nience system. It is not a substitute for
active driver involvement. It is always the
driver’s responsibility to be attentive of
road, traffic, and weather conditions,
vehicle speed, distance to the vehicle
ahead; and, most importantly, brake opera -
tion 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 and death or serious personal
injury.
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184STARTING AND OPERATING
When An ACC Distance Is Also Set:
When you use the SET (-) button to decel -
erate, if the engine’s braking power does not
slow the vehicle sufficiently to reach the set
speed, the brake system will automatically
slow the vehicle.
The ACC system decelerates the vehicle to a
full stop when following the vehicle in front. If
your vehicle follows the vehicle in front to a
standstill, after two seconds the driver will
either have to push the RES (resume) button,
or apply the accelerator pedal to reengage
the ACC to the existing set speed.
The ACC system maintains set speed when
driving uphill and downhill. However, a slight
speed change on moderate hills is normal. In
addition, downshifting may occur while
climbing uphill or descending downhill. This
is normal operation and necessary to main -
tain set speed. When driving uphill and down -
hill, the ACC system will cancel if the braking
temperature exceeds normal range (over -
heated).
Setting The Following Distance In ACC
The specified following distance for Adaptive
Cruise Control (ACC) can be set by varying the
distance setting between four bars (longest),
three bars (long), two bars (medium) and one
bar (short). Using this distance setting and the
vehicle speed, ACC calculates and sets the
distance to the vehicle ahead. This distance
setting displays in the instrument cluster
display.

Distance Settings
To increase the distance setting, push the
Distance Increase button and release. Each
time the button is pushed, the distance setting
increases by one bar (longer).
To decrease the distance setting, push the
Distance Decrease button and release. Each
time the button is pushed, the distance setting
decreases by one bar (shorter).
If there is no vehicle ahead, the vehicle will
maintain the set speed. If a slower moving
vehicle is detected in the same lane, the
instrument cluster displays the ACC Set With
Target Detected Indicator Light, and the system
adjusts vehicle speed automatically to maintain
the distance setting, regardless of the set
speed.
The vehicle will then maintain the set distance
until:
The vehicle ahead accelerates to a speed
above the set speed.
The vehicle ahead moves out of your lane or
view of the sensor.
The distance setting is changed.
The system disengages.
1 — Longest Distance Setting (Four Bars)
2 — Long Distance Setting (Three Bars)
3 — Medium Distance Setting (Two Bars)
4 — Short Distance Setting (One Bar)

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STARTING AND OPERATING185
The maximum braking applied by ACC is limited;
however, the driver can always apply the brakes
manually, if necessary.
NOTE:
The brake lights will illuminate whenever the
ACC system applies the brakes.
A Proximity Warning will alert the driver if ACC
predicts that its maximum braking level is not
sufficient to maintain the set distance. If this
occurs, a visual alert “BRAKE” will flash in the
instrument cluster display and a chime will
sound while ACC continues to apply its
maximum braking capacity.
NOTE:
The “BRAKE!” Screen in the instrument cluster
display is a warning for the driver to take action
and does not necessarily mean that the
Forward Collision Warning system is applying
the brakes autonomously.
Overtake Aid
When driving with Adaptive Cruise Control (ACC)
engaged, and following a vehicle, the system
will provide an additional acceleration up to the
ACC set speed to assist in passing the vehicle. This additional acceleration is triggered when
the driver utilizes the left turn signal and will
only be active when passing on the left hand
side.
ACC Operation At Stop
If the ACC system brings your vehicle to a
standstill while following the vehicle in front,
your vehicle will resume motion without any
diver intervention if the vehicle in front starts
moving within two seconds.
If the vehicle in front does not start moving
within two seconds of your vehicle coming to a
standstill, the driver will either have to push the
RES (resume) button, or apply the accelerator
pedal to reengage the ACC to the existing set
speed.
NOTE:
After the ACC system holds your vehicle at a
standstill for approximately three consecutive
minutes, the parking brake will be activated,
and the ACC system will be cancelled.
While ACC is holding your vehicle at a standstill,
if the driver seat belt is unbuckled or the driver
door is opened, the parking brake will be
activated, and the ACC system will be cancelled.
Display Warnings And Maintenance
“Wipe Front Radar Sensor In Front Of Vehicle”
Warning
The “ACC/FCW Unavailable Wipe Front Radar
Sensor” warning will display and also a chime
will indicate when conditions temporarily limit
system performance.
This most often occurs at times of poor visibility,
such as in snow or heavy rain. The ACC system
may also become temporarily blinded due to
obstructions, such as mud, dirt or ice. In these
cases, the instrument cluster display will display
“ACC/FCW Unavailable Wipe Front Radar
Sensor” and the system will deactivate.
The “ACC/FCW Unavailable Wipe Front Radar
Sensor” message can sometimes be displayed
while driving in highly reflective areas (i.e. ice
WARNING!
When the ACC system is resumed, the driver
must ensure that there are no pedestrians,
vehicles or objects in the path of the vehicle.
Failure to follow these warnings can result in
a collision and death or serious personal
injury.
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STARTING AND OPERATING209

1. Put the vehicle in PARK and switch the
ignition off.

2. Push the center-rear edge of the fuel filler door (3 o'clock position) and release to
open.
Fuel Filler Door

3. Insert the fuel nozzle fully into the filler pipe, the nozzle opens and holds both flapper
doors while refueling.

Fuel Filler

4. When the fuel nozzle “clicks” or shuts off, the fuel tank is full. 5. Keep the nozzle in the filler for five seconds
after nozzle clicks to allow fuel to drain from
the nozzle.
6. Remove the fuel filler nozzle.
7. To close the fuel filler door, push the center-rear edge (3 o’clock position) of the
fuel filler door and then release. The fuel
filler door will latch closed.
NOTE:
In certain cold conditions, ice may prevent the
fuel filler door from opening. If this occurs,
lightly push on the fuel filler door around the
perimeter to break the ice build up.
WARNING!
Never have any smoking materials lit in or
near the vehicle when the fuel door is open
or the tank is being filled.
Never add fuel when the engine is running.
This is in violation of most state and federal
fire regulations and may cause the MIL to
turn on.
A fire may result if gasoline is pumped into
a portable container that is inside of a
vehicle. You could be burned. Always place
gas containers on the ground while filling.
CAUTION!
To avoid fuel spillage and overfilling, do not
“top off” the fuel tank after filling.
WARNING!
Always place container on the ground
before filling.
Keep the pump nozzle in contact with the
container when you are filling it.
Use only approved containers for flam -
mable liquid.
Do not leave container unattended while
filling.
A static electric charge could cause a spark
and fire hazard.
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210STARTING AND OPERATING
REFUELING THE VEHICLE — DIESEL ENGINE
The capless fuel filler is located on the left side
of the vehicle.
The capless system is sealed by two flapper
doors.

1. Put the vehicle in PARK and switch the
ignition off.

2. Open the fuel filler door.

Diesel Fuel And Diesel Exhaust Fluid Fill Location

3. Insert the fuel nozzle fully into the filler pipe – the nozzle opens and holds the flapper
door while refueling. 4. Fill the vehicle with fuel – when the fuel
nozzle “clicks” or shuts off, the fuel tank is
full.
5. Remove the fuel nozzle and close the fuel door.
AVOID USING CONTAMINATED FUEL
Fuel that is contaminated by water or dirt can
cause severe damage to the engine fuel
system. Proper maintenance of the engine fuel
filter and fuel tank is essential Ú page 409.
BULK FUEL STORAGE — DIESEL FUEL
If you store quantities of fuel, good
maintenance of the stored fuel is also essential.
Fuel contaminated with water will promote the
growth of “microbes.” These microbes form
“slime” that will clog the fuel filtration system
and lines. Drain condensation from the supply
tank and change the line filter on a regular
basis.
NOTE:
When a diesel engine is allowed to run out of
fuel, air is pulled into the fuel system.
If the vehicle will not start Úpage 414.
1 — Diesel Exhaust Fluid (DEF) Fill Location
2 — Diesel Fuel Fill Location
WARNING!
Never have any smoking materials lit in or
near the vehicle when the fuel door is open
or the tank is being filled.
Never add fuel when the engine is running.
This is in violation of most state and federal
fire regulations and may cause the
“Malfunction Indicator Light” to turn on.
A fire may result if fuel is pumped into a
portable container that is inside of a
vehicle. You could be burned. Always place
fuel containers on the ground while filling.
CAUTION!
To avoid fuel spillage and overfilling, do not
“top off” the fuel tank after filling.
WARNING!
Do not open the high pressure fuel system
with the engine running. Engine operation
causes high fuel pressure. High pressure fuel
spray can cause serious injury or death.

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STARTING AND OPERATING221
(Continued)
NOTE:
Trailers may look different during day and night
conditions. In such cases, the trailer may need
to recalibrate.
Some trailers (such as boat trailers) will need to
recalibrate while loaded and unloaded.
NOTE:
The system may not detect a trailer in low
light conditions. In sunny conditions, the
performance may be degraded as shadows
pass over the trailer.
The driver is always responsible for safe oper -
ation of truck and trailer.
The driver is always in control of the truck as
well as the trailer and is responsible for
controlling the throttle and brakes.
The system may not function when the
camera lens is blocked, blurred (covered with
water, snow, ice, dirt, etc) and will not work
unless the tailgate is upright and fully
latched.
TOWING REQUIREMENTS
To promote proper break-in of your new vehicle
drivetrain components, the following guidelines
are recommended.
Perform the maintenance listed in the
Scheduled Servicing section for the proper
maintenance intervals Ú page 395. When
towing a trailer, never exceed the GAWR or
GCWR ratings.
CAUTION!
Do not tow a trailer at all during the first
500 miles (805 km) the new vehicle is driven. The engine, axle or other parts could
be damaged.
Then, during the first 500 miles (805 km) that a trailer is towed, do not drive over
50 mph (80 km/h) and do not make starts
at full throttle. This helps the engine and
other parts of the vehicle wear in at the
heavier loads.
WARNING!
Make certain that the load is secured in the
trailer and will not shift during travel. When
trailering cargo that is not fully secured,
dynamic load shifts can occur that may be
difficult for the driver to control. You could
lose control of your vehicle and have a colli -
sion.
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.
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