2019 Ram 3500 service

GETTING TO KNOW YOUR INSTRUMENT PANEL 185
— 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 (kilome -
ters) at speeds greater than 30 mph (48 km/h), see an autho -
rized 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.
• 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.
— Low Washer Fluid Warning Light — If Equipped
This warning light will illuminate when the windshield
washer fluid is low.
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.
3

GETTING TO KNOW YOUR INSTRUMENT PANEL 187
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 pres-
sure telltale.
Your vehicle has also been equipped with a TPMS malfunc -
tion 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 indi -
cator 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 replace -
ment or alternate tires and wheels allow the TPMS to
continue to function properly. — Anti-Lock Brake (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. 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 your
authorized dealer to have your sensor function checked.
3

188 GETTING TO KNOW YOUR INSTRUMENT PANEL
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.
— 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.
Yellow Indicator Lights
— Forward Collision Warning Off Indicator Light — If
Equipped
This indicator light illuminates to indicate that Forward
Collision Warning is off.

— 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.

192 GETTING TO KNOW YOUR INSTRUMENT PANEL
— 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.
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.
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.

GETTING TO KNOW YOUR INSTRUMENT PANEL 193
Onboard Diagnostic System (OBD II) Cybersecurity
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”.

EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass an
inspection of your vehicle's emissions control system. Failure
to pass could prevent vehicle registration.For states that require an Inspection and Mainte -
nance (I/M), this check verifies the “Malfunction
Indicator Light (MIL)” is functioning and is not on
when the engine is running, and that the OBD II system is
ready for testing.
Normally, the OBD II system will be ready. The OBD II
system may not be ready if your vehicle was recently
serviced, recently had a dead battery or a battery replace -
ment. If the OBD II system should be determined not ready
for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition actuated test, which you
can use prior to going to the test station. To check if your
vehicle's OBD II system is ready, you must do the following:
1. Cycle the ignition switch to the ON position, but do not crank or start the engine.
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
accident involving serious injury or death.
• Access, or allow others to access, information stored in your vehicle systems, including personal infor -
mation.
3

194 GETTING TO KNOW YOUR INSTRUMENT PANEL
NOTE:
If you crank or start the engine, you will have to start this test
over.
2. As soon as you cycle the ignition switch to the ON posi-
tion, you will see the “Malfunction Indicator Light (MIL)”
symbol come on as part of a normal bulb check.
3. Approximately 15 seconds later, one of two things will happen:
• The MIL will flash for about ten seconds and thenreturn to being fully illuminated until you turn OFF the
ignition or start the engine. This means that your
vehicle's OBD II system is not ready and you should
not proceed to the I/M station.
• The MIL will not flash at all and will remain fully illu -
minated until you place the ignition in the off position
or start the engine. This means that your vehicle's OBD
II system is ready and you can proceed to the I/M
station. If your OBD II system is
not ready, you should see an autho -
rized dealer or repair facility. If your vehicle was recently
serviced or had a battery failure or replacement, you may
need to do nothing more than drive your vehicle as you
normally would in order for your OBD II system to update.
A recheck with the above test routine may then indicate that
the system is now ready.
Regardless of whether your vehicle's OBD II system is ready
or not, if the MIL is illuminated during normal vehicle oper -
ation you should have your vehicle serviced before going to
the I/M station. The I/M station can fail your vehicle
because the MIL is on with the engine running.

196 SAFETY
ABS is designed to function with the OEM tires. Modification
may result in degraded ABS performance.
Anti-Lock Brake Warning Light
The yellow “Anti-Lock Brake Warning Light” will turn on
when the ignition is turned to the ON/RUN mode and may
stay on for as long as four seconds.
If the “Anti-Lock Brake 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 “Anti-Lock Brake Warning Light” is on.

If the “Anti-Lock Brake Warning Light” is on, the brake
system should be serviced as soon as possible to restore the
benefits of anti-lock brakes. If the “Anti-Lock Brake Warning
Light” does not come on when the ignition is turned to the
ON/RUN mode, have the light repaired as soon as possible.
Electronic Brake Control System
Your vehicle is equipped with an advanced Electronic Brake
Control system (EBC). This system includes Electronic Brake
Force Distribution (EBD), Anti-Lock Brake System (ABS),
Brake Assist System (BAS), Hill Start Assist (HSA), Traction
Control System (TCS), Electronic Stability Control (ESC),
and Electronic Roll Mitigation (ERM). 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).
• The ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase braking
or steering efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the traction
afforded.
• The ABS cannot prevent collisions, including those resulting from excessive speed in turns, following
another vehicle too closely, or hydroplaning.
• The capabilities of an ABS equipped vehicle must never be exploited in a reckless or dangerous manner
that could jeopardize the user’s safety or the safety of
others.
WARNING! (Continued)

SAFETY 197
Electronic Brake Force Distribution (EBD)
This function manages the distribution of the braking torque
between the front and rear axles by limiting braking pressure
to the rear axle. This is done to prevent overslip of the rear
wheels to avoid vehicle instability, and to prevent the rear
axle from entering ABS before the front axle.
Brake System Warning Light
The red “Brake System Warning Light” will turn on when
the ignition is turned to 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 func-
tioning properly and that immediate service is required. If
the “Brake System Warning Light” does not come on when
the ignition is turned to the ON/RUN mode, have the light
repaired as soon as possible. Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking capa
-
bility 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 stop -
ping 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.
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.
4