light Ram 3500 Chassis Cab 2018 Repair Manual

— Cargo Light — If Equipped
The cargo light will illuminate when the cargo light is
activated by pushing the cargo light button on the head-
light switch.
— 4WD Low Indicator Light — If Equipped
This light alerts the driver that the vehicle is in the
four-wheel drive LOW mode. The front and rear drive-
shafts are mechanically locked together forcing the front
and rear wheels to rotate at the same speed. Low range
provides a greater gear reduction ratio to provide increased
torque at the wheels.
Refer to “Four-Wheel Drive Operation — If Equipped” in
“Starting And Operating” for further information on four-
wheel drive operation and proper use.
– 4WD Indicator Light — If Equipped
This light alerts the driver that the vehicle is in the
four-wheel drive mode, and the front and rear driveshafts
are mechanically locked together forcing the front and rear
wheels to rotate at the same speed.
— 2WD Indicator Light — If Equipped
This light alerts the driver that the vehicle is in the
two-wheel drive mode.
Green Indicator Lights
— Park/Headlight On Indicator Light
This indicator will illuminate when the park lights or
headlights are turned on.
— Front Fog Indicator Light — If Equipped
This indicator will illuminate when the front fog lights are
on.
— Turn Signal Indicator Lights
When the left or right turn signal is activated, the turn
signal indicator will flash independently and the corre-
sponding 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.
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— Cruise Control SET Indicator Light
This light will turn on when the speed control is set to the
desired speed. Refer to “Speed Control” in “Starting And
Operating” for further information.
White Indicator Lights
— Cruise Control ON Indicator
This light will turn on when the speed control is on, but not
set.
— Speed Control SET Indicator Light
This light will turn on when the speed control is set. Refer
to “Speed Control” in “Starting And Operating” for further
information.
Blue Indicator Lights
— High Beam Indicator Light
This indicator shows 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 passscenario.
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 prop-
erly, 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
your 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.
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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 ac-
cess this information to assist with the diagnosis and
service of your vehicle and emissions system.
WARNING!
•ONLY an authorized service technician should con-
nect equipment to the OBD II connection port in
order to 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
information.
For further information, refer to “Cybersecurity” in “Mul-
timedia”.
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 notbe 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 follow-
ing:
1. Cycle the ignition switch to the ON position, but do not crank or start the engine.
NOTE: If you crank or start the engine, you will have to
start this test over.
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GETTING TO KNOW YOUR INSTRUMENT PANEL 157

2. As soon as you cycle the ignition switch to the ONposition, 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 then return
to being fully illuminated until you turn OFF the igni-
tion or start the engine. This means that your vehicle’s
OBD II system is not readyand you should notproceed
to the I/M station.
• The MIL will not flash at all and will remain fully
illuminated until you place the ignition in the off posi-
tion or start the engine. This means that your vehicle’s
OBD II system is readyand you can proceed to the I/M
station. If your OBD II system is
not ready,you should see your
authorized 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 operation 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.
158 GETTING TO KNOW YOUR INSTRUMENT PANEL

SAFETY FEATURES
Anti-Lock Brake System (ABS)
The Anti-Lock Brake System (ABS) provides increased
vehicle stability and brake performance under most brak-
ing conditions. The system automatically prevents wheel
lock, and enhances vehicle control during braking.
The ABS performs a self-check cycle to ensure that the ABS
is working properly each time the vehicle is started and
driven. During this self-check, you may hear a slight
clicking sound as well as some related motor noises.
ABS is activated during braking when the system detects
one or more wheels begin to lock. Road conditions such as
ice, snow, gravel, bumps, railroad tracks, loose debris, or
panic stops may increase the likelihood of ABS activa-
tion(s).
You also may experience the following when ABS activates:
•The ABS motor noise (it may continue to run for a short
time after the stop).
• The clicking sound of solenoid valves.
• Brake pedal pulsations.
• A slight drop of the brake pedal at the end of the stop. These are all normal characteristics of ABS.
WARNING!
•
The ABS contains sophisticated electronic equip-
ment that may be susceptible to interference caused
by improperly installed or high output radio trans-
mitting equipment. This interference can cause pos-
sible loss of anti-lock braking capability. Installation
of such equipment should be performed by qualified
professionals.
• Pumping of the Anti-Lock Brakes will diminish their
effectiveness and may lead to a collision. Pumping
makes the stopping distance longer. Just press firmly
on your brake pedal when you need to slow down or
stop.
• The ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase brak-
ing 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.
(Continued)
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WARNING!(Continued)
•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.
ABS is designed to function with the OEM tires. Modifica-
tion 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 sys-
tem will continue to operate normally if the “Brake System
Warning Light” is not 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 Warn-
ing 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 Elec-
tronic 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).
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.
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SAFETY 161

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
functioning properly and that immediate service is re-
quired. 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
capability during emergency braking maneuvers. The sys-
tem 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.
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 capa-
bilities 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.
Hill Start Assist (HSA)
The HSA system 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.
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The following conditions must be met in order for HSA to
activate:
•The feature must be enabled.
• The vehicle must be stopped.
• Park brake must be off.
• 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. For vehicles equipped with a
manual transmission, if the clutch is pressed, HSA will
remain active.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 ve-
hicles, 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.
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SAFETY 163

Towing With HSA
HSA will also provide assistance to mitigate roll back while
towing a 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 pressure 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 resum-
ing acceleration, manually activate the trailer brake
or apply more vehicle brake pressure prior to releas-
ing 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 transmission in PARK.
• Failure to follow these warnings can result in a
collision or serious personal injury.
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 your instrument cluster display,
refer to “Instrument Cluster Display” in “Getting To
Know Your Instrument Panel” for further information.
• If disabling HSA using Uconnect Settings, refer to
“Uconnect Settings” in “Multimedia” for further infor-
mation.
For vehicles not equipped with an instrument cluster
display, perform the following steps:
1. Center the steering wheel (front wheels pointing straight forward).
2. Shift the transmission into PARK.
3. Apply the parking brake.
4. Start the engine.
5. Rotate the steering wheel slightly more than one-half turn to the left.
164 SAFETY

6. Push the “ESC Off” button located in the lower switchbank below the climate control four times within 20
seconds. The “ESC Off Indicator Light” should turn on
and turn off two times.
7. Rotate the steering wheel back to center and then an additional slightly more than one-half turn to the right.
8. Turn the ignition to the OFF mode and then back to ON. If the sequence was completed properly, the “ESC Off
Indicator Light” will blink several times to confirm HSA
is disabled.
9. Repeat these steps if you want to return this feature to its previous setting.
Traction Control System (TCS)
This system 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 similar 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 ESC are in a reduced mode.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESC corrects
for oversteering or understeering of the vehicle by apply-
ing the brake of the appropriate wheel(s) to assist in
counteracting the oversteer or understeer condition. En-
gine power may also be reduced to help the vehicle
maintain the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESC applies the brake of the appropriate
wheel to assist in counteracting the oversteer or understeer
condition.
•
Oversteer — when the vehicle is turning more than
appropriate for the steering wheel position.
• Understeer — when the vehicle is turning less than
appropriate for the steering wheel position.
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SAFETY 165