2020 Ram 3500 warning light

GETTING TO KNOW YOUR INSTRUMENT PANEL133
NOTE:
This light may turn on if the accelerator and
brake pedals are pressed at the same time.
If the light continues to flash when the vehicle is
running, immediate service is required and you
may experience reduced performance, an
elevated/rough idle, or engine stall and your
vehicle may require towing. The light will come
on when the ignition is placed in the ON/RUN or
ACC/ON/RUN position and remain on briefly as
a bulb check. If the light does not come on
during starting, have the system checked by an
authorized dealer.
Trailer Brake Disconnected Warning Light
This warning light will illuminate when
the Trailer Brake has been
disconnected.
Refer to “Trailer Towing” in “Starting And
Operating” for further information.
Transmission Temperature Warning Light
— If Equipped
This warning light will illuminate to
warn of a high transmission fluid
temperature. This may occur with
strenuous usage such as trailer towing. If this light turns on, stop the vehicle and
run the engine at idle or slightly faster, with the
transmission in PARK (P) or NEUTRAL (N), until
the light turns off. Once the light turns off, you
may continue to drive normally.
Door Open Warning Light
This indicator will illuminate when a
door is ajar/open and not fully closed.
NOTE:
If the vehicle is moving there will also be a single
chime.
YELLOW WARNING LIGHTS
Adaptive Cruise Control (ACC) Fault
Warning Light — If Equipped
This warning light will illuminate to
indicate a fault in the ACC system.
Contact a local authorized dealer for
service.
For further information, refer to “Adaptive
Cruise Control (ACC)” in “Starting And
Operating.”
Air Suspension Fault Warning Light — If
Equipped
This light will illuminate when a fault is
detected with the air suspension
system.
Refer to “Air Suspension System — If Equipped”
in “Starting And Operating” for further
information.
Engine Check/Malfunction Indicator
Warning Light (MIL)
The Engine Check/Malfunction
Indicator Light (MIL) is a part of an
Onboard Diagnostic System called
OBD II that monitors engine and
WARNING!
If you continue operating the vehicle when
the Transmission Temperature Warning Light
is illuminated you could cause the fluid to boil
over, come in contact with hot engine or
exhaust components and cause a fire.
CAUTION!
Continuous driving with the Transmission
Temperature Warning Light illuminated will
eventually cause severe transmission
damage or transmission failure.
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134GETTING TO KNOW YOUR INSTRUMENT PANEL
automatic transmission control systems. This
warning light will illuminate when the ignition is
in the ON/RUN position before engine start. If
the bulb does not come on when turning the
ignition switch from OFF to ON/RUN, have the
condition checked promptly.
Certain conditions, such as a loose or missing
gas cap, poor quality fuel, etc., may illuminate
the light after engine start. The vehicle should
be serviced if the light stays on through several
typical driving styles. In most situations, the
vehicle will drive normally and will not require
towing.
When the engine is running, the MIL may flash
to alert serious conditions that could lead to
immediate loss of power or severe catalytic
converter damage. The vehicle should be
serviced by an authorized dealer as soon as
possible if this occurs.Electronic Stability Control (ESC) Active
Warning Light — If Equipped
This warning light will indicate when
the Electronic Stability Control system
is Active. The “ESC Indicator Light” in
the instrument cluster will come on
when the ignition is placed in the ON/RUN or
ACC/ON/RUN position, and when ESC is
activated. It should go out with the engine
running. If the “ESC Indicator Light” comes on
continuously with the engine running, a
malfunction has been detected in the ESC
system. If this warning 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 OFF Indicator Light” and the “ESC
Indicator Light” come on momentarily each
time the ignition is placed in the ON/RUN or
ACC/ON/RUN position.
WARNING!
A malfunctioning catalytic converter, as
referenced above, can reach higher
temperatures than in normal operating
conditions. This can cause a fire if you drive
slowly or park over flammable substances
such as dry plants, wood, cardboard, etc. This
could result in death or serious injury to the
driver, occupants or others.
CAUTION!
Prolonged driving with the Malfunction
Indicator Light (MIL) on could cause damage
to the vehicle control system. It also could
affect fuel economy and driveability. If the
MIL is flashing, severe catalytic converter
damage and power loss will soon occur.
Immediate service is required.

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GETTING TO KNOW YOUR INSTRUMENT PANEL135
The ESC system will make buzzing or clicking
sounds when it is active. This is normal; the
sounds will stop when ESC becomes inactive.
This light will come on when the vehicle is in
an ESC event.
Electronic Stability Control (ESC) OFF
Warning Light — If Equipped
This warning light indicates the
Electronic Stability Control (ESC) is
off.
Each time the ignition is turned to ON/RUN or
ACC/ON/RUN, the ESC system will be on, even
if it was turned off previously.
LaneSense Warning Light — If Equipped
The LaneSense system provides the
driver with visual and steering torque
warnings when the vehicle starts to
drift out of its lane unintentionally
without the use of a turn signal.
When the LaneSense system senses a lane
drift situation, the LaneSense indicator
changes from solid green to solid yellow.
When the LaneSense system senses the lane
has been approached and is in a lane depar -
ture situation, the LaneSense indicator
changes from solid white/green to flashing
yellow.
Refer to “LaneSense – If Equipped” in
“Starting And Operating” for further informa -
tion.
Service LaneSense Warning Light — If
Equipped
This warning light will illuminate when
the LaneSense system is not
operating and requires service.
Please see an authorized dealer.
Low Washer Fluid Warning Light
This warning light will illuminate when
the windshield washer fluid is low.
Refer to “Engine Compartment” in
“Servicing And Maintenance” for further
information.
Low Fuel Warning Light
When the fuel level reaches
approximately 3.2 gal (12 L) this light
will turn on, and remain on until fuel is
added.
A single warning chime will sound with Low Fuel
Warning.
Low Coolant Level Warning Light
This telltale will turn on to indicate the
vehicle coolant level is low.
Refer to “Fluids And Lubricants” in
“Technical Specifications” for further
information.
Loose Fuel Filler Cap Warning Light — If
Equipped
This warning light will illuminate when
the fuel filler cap is loose. Properly
close the filler cap to disengage the
light. If the light does not turn off,
please see an authorized dealer.
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136GETTING TO KNOW YOUR INSTRUMENT PANEL
Trailer Merge Assist Indicator Light — If
Equipped
This indicator light will illuminate to
indicate when Trailer Merge Assist
has been activated.
Refer to “Blind Spot Monitoring (BSM)” in
“Safety” for further information.
Tire Pressure Monitoring System (TPMS)
Warning Light
The warning light switches on and a
message is displayed to indicate that
the tire pressure is lower than the
recommended value and/or that slow
pressure loss is occurring. In these cases,
optimal tire duration and fuel consumption may
not be guaranteed.
Should one or more tires be in the condition
mentioned above, the display will show the
indications corresponding to each tire. Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommended
by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. If your
vehicle has tires of a different size than the size
indicated on the vehicle placard or tire inflation
pressure label, you should determine the
proper tire inflation pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a Tire Pressure Monitoring
System (TPMS) that illuminates a low tire
pressure telltale when one or more of your tires
is significantly under-inflated. Accordingly, when
the low tire pressure telltale illuminates, you
should stop and check your tires as soon as
possible, and inflate them to the proper
pressure. Driving on a significantly
under-inflated tire causes the tire to overheat
and can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life, and
may affect the vehicle’s handling and stopping
ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure, even if under-inflation has not reached the level
to trigger illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The TPMS
malfunction indicator is combined with the low
tire pressure telltale. When the system detects
a malfunction, the telltale will flash for
approximately one minute and then remain
continuously illuminated. This sequence will
continue upon subsequent vehicle start-ups as
long as the malfunction exists. When the
malfunction indicator is illuminated, the system
may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction telltale after replacing one or
more tires or wheels on your vehicle to ensure
that the replacement or alternate tires and
wheels allow the TPMS to continue to function
properly.
CAUTION!

Do not continue driving with one or more flat
tires as handling may be compromised. Stop the
vehicle, avoiding sharp braking and steering. If a
tire puncture occurs, repair immediately using
the dedicated tire repair kit and contact an
authorized dealer as soon as possible.

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GETTING TO KNOW YOUR INSTRUMENT PANEL137
Anti-Lock Brake System(ABS) Warning
Light

This warning light monitors the
Anti-Lock Brake System (ABS). The
light will turn on when the ignition is
placed in the ON/RUN or ACC/ON/
RUN position and may stay on for as long as
four seconds.

If the ABS light remains on or turns on while
driving, then the Anti-Lock portion of the brake system is not functioning and service is
required as soon as possible. However, the
conventional brake system will continue to
operate normally, assuming the Brake Warning
Light is not also on.
If the ABS light does not turn on when the
ignition is placed in the ON/RUN or ACC/ON/
RUN position, have the brake system inspected
by an authorized dealer.
Rear Axle Locker Fault Indicator Light — If
Equipped
This warning light will illuminate to
indicate when a rear axle locker fault
has been detected.
Refer to “Axle Locker System — Power Wagon
Models Only (If Equipped)” in “Starting And
Operating” for further information.
Service Forward Collision Warning (FCW)
Light — If Equipped
This warning light will illuminate to
indicate a fault in the Forward
Collision Warning System. Contact an
authorized dealer for service.
Refer to "Forward Collision Warning (FCW)" in
"Safety" for further information.
Service 4WD Warning Light — If Equipped
This warning light will illuminate to
signal a fault with the 4WD system. If
the light stays on or comes on during
driving, it means that the 4WD system
is not functioning properly and that service is
required. We recommend you drive to the
nearest service center and have the vehicle
serviced immediately.
Speed Control Fault Warning Light

This warning light will illuminate to
indicate the Speed Control System is
not functioning properly and service is
required. Contact an authorized dealer.

Sway Bar Fault Warning Light
This light will illuminate when there is
a fault in the sway bar disconnect
system.
Refer to “Stabilizer/Sway Bar System — Power
Wagon Only” in “Starting And Operating” for
further information.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures
and warning have been established for the
tire size equipped on your vehicle.
Undesirable system operation or sensor
damage may result when using replacement
equipment that is not of the same size, type,
and/or style. Aftermarket wheels can cause
sensor damage. Using aftermarket tire
sealants may cause the Tire Pressure
Monitoring System (TPMS) sensor to become
inoperable. After using an aftermarket tire
sealant it is recommended that you take your
vehicle to an authorized dealer to have your
sensor function checked.
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138GETTING TO KNOW YOUR INSTRUMENT PANEL
YELLOW INDICATOR LIGHTS
Forward Collision Warning Off Indicator
Light — If Equipped
This indicator light illuminates to
indicate that Forward Collision
Warning is off.
Refer to “Auxiliary Driving Systems” in “Safety”
for further information.
Air Suspension Payload Protection
Indicator Light — If Equipped
This indicator light will illuminate to
indicate that the maximum payload
may have been exceeded or load
leveling cannot be achieved at its
current ride height. Protection Mode will
automatically be selected in order to “protect”
the air suspension system, air suspension
adjustment is limited due to payload.
TOW/HAUL Indicator Light
This indicator light will illuminate
when TOW/HAUL mode is selected.
Refer to “Trailer Towing” in “Starting
And Operating” for further information.
Cargo Light — If Equipped
This indicator light will illuminate
when the cargo light is activated by
pushing the cargo light button on the
headlight switch.
Cold Ambient Derate Mode Indicator Light
— If Equipped
This indicator light will illuminate
when a derate (engine power
reduction) is activated for protection
of the turbocharger in cold ambient
temperatures.
For further information, refer to “Instrument
Cluster Display” in “Getting To Know Your
Instrument Panel”.
Diesel Exhaust Brake Indicator Light — If
Equipped
This indicator light will illuminate
when the Diesel Exhaust Brake has
been activated, and is in full strength
mode.
Refer to “Diesel Exhaust Brake (Engine
Braking)” in “Starting And Operating” for further
information.
Sway Bar Indicator Light — If Equipped
This indicator light will illuminate
when the front sway bar is
disconnected.
Refer to “Stabilizer/Sway Bar System — Power
Wagon Only” in “Starting And Operating” for
further information.
Snowplow Mode Indicator Light — If
Equipped
This indicator light will illuminate
when Snowplow Mode has been
activated.
Refer to “Snowplow” in “Starting And
Operating” for further information.
Air Suspension Alternate Trailer Height
Indicator Light — If Equipped
This light will illuminate when the air
suspension system is set to the
Alternate Trailer Height setting.
Refer to “Air Suspension System — If Equipped”
in “Starting And Operating” for further
information.

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GETTING TO KNOW YOUR INSTRUMENT PANEL141
to provide visual and torque warnings if an
unintentional lane departure occurs.
Refer to “LaneSense — If Equipped” in “Starting
And Operating” for further information.
Front Fog Indicator Light — If Equipped
This indicator light will illuminate
when the front fog lights are on.
Refer to “Exterior Lights” in “Getting
To Know Your Vehicle” for further information.
Turn Signal Indicator Lights
When the left or right turn signal is
activated, the turn signal indicator will
flash independently and the
corresponding exterior turn signal
lamps will flash. Turn signals can be activated
when the multifunction lever is moved down
(left) or up (right).
NOTE:
A continuous chime will sound if the vehicle is
driven more than 1 mile (1.6 km) with either
turn signal on.
Check for an inoperative outside light bulb if
either indicator flashes at a rapid rate.

If equipped with fog lamps, the fog lamp on the
side of the activated turn signal will also illumi -
nate to provide additional light when turning.

Cruise Control Set Indicator Light — If
Equipped
This indicator light will illuminate
when the cruise control is set to the
desired speed. Refer to “Speed
Control” in “Starting And Operating”
for further information.
WHITE INDICATOR LIGHTS

Adaptive Cruise Control (ACC) Ready Light
— If Equipped

This light will illuminate when the vehicle
equipped with Adaptive Cruise Control
(ACC) has been turned on but not set.

Refer to “Adaptive Cruise Control (ACC) — If
Equipped” in “Starting And Operating” for
further information.
Cruise Control Ready Indicator

This indicator light will illuminate
when the cruise control is ready,
but not set. Refer to “Speed Control”
in “Starting And Operating” for
further information.

Hill Descent Control (HDC) Indicator Light
— If Equipped
This indicator shows when the Hill
Descent Control (HDC) feature is
turned on. The lamp will be on solid
when HDC is armed. HDC can only be
armed when the transfer case is in the “4WD
LOW” position and the vehicle speed is less
then 20 mph (32 km/h). If these conditions are
not met while attempting to use the HDC
feature, the HDC indicator light will flash on/off.
LaneSense Indicator Light — If Equipped
When the LaneSense system is ON,
but not armed, the LaneSense
indicator light illuminates solid white.
This occurs when only left, right, or
neither lane line has been detected. If a single
lane line is detected, the system is ready to
provide only visual warnings if an unintentional
lane departure occurs on the detected lane line.
Refer to “LaneSense — If Equipped” in “Starting
And Operating” for further information.
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142GETTING TO KNOW YOUR INSTRUMENT PANEL
BLUE INDICATOR LIGHTS
High Beam Indicator Light
This indicator light will illuminate to
indicate that the high beam
headlights are on. With the low beams
activated, push the multifunction
lever forward (toward the front of the vehicle) to
turn on the high beams. Pull the multifunction
lever rearward (toward the rear of the vehicle) to
turn off the high beams. If the high beams are
off, pull the lever toward you for a temporary
high beam on, "flash to pass" scenario.
ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated
Onboard Diagnostic system called OBD II. This
system monitors the performance of the
emissions, engine, and transmission control
systems. When these systems are operating
properly, your vehicle will provide excellent
performance and fuel economy, as well as
engine emissions well within current
government regulations.
If any of these systems require service, the OBD
II system will turn on the Malfunction Indicator
Light (MIL). It will also store diagnostic codes and other information to assist your service
technician in making repairs. Although your
vehicle will usually be drivable and not need
towing, see an authorized dealer for service as
soon as possible.
ONBOARD DIAGNOSTIC SYSTEM
(OBD II) C
YBERSECURITY
Your vehicle is required to have an Onboard
Diagnostic system (OBD II) and a connection
port to allow access to information related to
the performance of your emissions controls. Authorized service technicians may need to
access this information to assist with the
diagnosis and service of your vehicle and
emissions system.
For further information, refer to “Cybersecurity”
in “Multimedia”.
CAUTION!
Prolonged driving with the MIL on could
cause further damage to the emission
control system. It could also affect fuel
economy and driveability. The vehicle must
be serviced before any emissions tests can
be performed.
If the MIL is flashing while the vehicle is
running, severe catalytic converter damage
and power loss will soon occur. Immediate
service is required.
WARNING!
ONLY an authorized service technician
should connect equipment to the OBD II
connection port in order to read the VIN,
diagnose, or service your vehicle.
If unauthorized equipment is connected to
the OBD II connection port, such as a
driver-behavior tracking device, it may:
Be possible that vehicle systems,
including safety related systems, could
be impaired or a loss of vehicle control
could occur that may result in an acci
-
dent involving serious injury or death.
Access, or allow others to access, infor -
mation stored in your vehicle systems,
including personal information.

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