2020 Ram 1500 Service

188 GETTING TO KNOW YOUR INSTRUMENT PANEL
— Service Stop/Start System Warning Light — If
Equipped
This warning light will illuminate when the Stop/Start
system is not functioning properly and service is required.
Contact an authorized dealer for service.
— 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.
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 to “protect” the air
suspension system, air suspension adjustment is limited due
to payload.
— 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.
— TOW/HAUL Indicator Light
This indicator light will illuminate when TOW/HAUL mode
is selected.
— 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.
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GETTING TO KNOW YOUR INSTRUMENT PANEL 195
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) 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 “Multi-
media”.

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
accident involving serious injury or death.
• Access, or allow others to access, information stored in your vehicle systems, including personal infor -
mation.
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196 GETTING TO KNOW YOUR INSTRUMENT PANEL
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 depleted 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.
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 10 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 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.
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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.
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SAFETY 199
ABS is designed to function with the Original Equipment
Manufacturer (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 (EBC) system. 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)
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200 SAFETY
Brake Assist System (BAS)
The Brake Assist System (BAS) is designed to optimize the
vehicle’s braking capability during emergency braking
maneuvers. The system detects an emergency braking situa-
tion 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. 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.
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.
Electronic Roll Mitigation (ERM)
The Electronic Roll Mitigation (ERM) system anticipates the
potential for wheel lift by monitoring the driver’s steering
wheel input and the speed of the vehicle. When ERM deter -
mines that the rate of change of the steering wheel angle and
vehicle’s speed are sufficient to potentially cause wheel lift,
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.
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SAFETY 215
The BSM system is designed not to issue an alert on
stationary objects such as guardrails, posts, walls, foliage,
berms, snow banks, car washes etc. However, occasionally
the system may alert on such objects. This is normal opera-
tion and your vehicle does not require service.
Stationary Objects The BSM system will not alert you of objects that are trav
-
eling in the opposite direction of the vehicle in adjacent
lanes.
Opposing Traffic
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SAFETY 225
• Medium• When the sensitivity of FCW is set to the “Medium”setting and the system status is “Only Warning”, this
allows the system to warn the driver of a possible colli -
sion with the vehicle in front using audible/visual
warnings.
• Near • When the sensitivity of FCW is set to the “Near” settingand the system status is “Only Warning”, this allows
the system to warn the driver of a possible closer colli -
sions with the vehicle in front using audible/visual
warnings.
• This setting provides less reaction time than the “Far” and “Medium” settings, which allows for a more
dynamic driving experience.
• More dynamic or aggressive drivers that want to avoid frequent warnings may prefer this setting. FCW Limited Warning
If the instrument cluster displays “ACC/FCW Limited Func
-
tionality” or “ACC/FCW Limited Functionality Clean Front
Windshield” momentarily, there may be a condition that
limits FCW functionality. Although the vehicle is still drive -
able under normal conditions, the active braking may not be
fully available. Once the condition that limited the system
performance is no longer present, the system will return to
its full performance state. If the problem persists, see an
authorized dealer.
Service FCW Warning
If the system turns off, and the instrument cluster displays:
• ACC/FCW Unavailable Service Required
• Cruise/FCW Unavailable Service Required
This indicates there is an internal system fault. Although the
vehicle is still drivable under normal conditions, have the
system checked by an authorized dealer.
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