service indicator Ram 2500 2020 User Guide

136GETTING TO KNOW YOUR INSTRUMENT PANEL
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 pres-
sure 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 approxi -
mately one minute and then remain continu -
ously 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.
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.
If the ABS light does not turn on when the igni
-
tion 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.
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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GETTING TO KNOW YOUR INSTRUMENT PANEL137
Service Forward Collision Warning (FCW)
Light — If Equipped
This warning light will illuminate to
indicate a fault in the Forward Colli-
sion 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.
Yellow Indicator Lights
Forward Collision Warning Off Indicator Light
— If Equipped
This indicator light illuminates to indi -
cate 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 auto -
matically be selected in order to “protect” the air suspension system, air suspension adjust
-
ment 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 informa -
tion.
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 reduc -
tion) 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”.
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GETTING TO KNOW YOUR INSTRUMENT PANEL139
4WD Lock Indicator Light
This light alerts the driver that the
vehicle is in the four-wheel drive LOCK
mode. The front and rear driveshafts
are mechanically locked together,
forcing the front and rear wheels to rotate at the
same speed.
Refer to “Four-Wheel Drive Operation” in
“Starting And Operating” for further information
on four-wheel drive operation and proper use.
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 driveshafts
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 opera -
tion and proper use.
4WD High Indicator Light — If Equipped
This light alerts the driver that the
vehicle is in the four-wheel drive HIGH
mode. The front and rear driveshafts
are mechanically locked together
forcing the front and rear wheels to rotate at the
same speed.
NEUTRAL Indicator Light — If Equipped
This light alerts the driver that the
4WD power transfer case is in the
NEUTRAL mode and the front and rear
driveshafts are disengaged from the
powertrain.
Low Diesel Exhaust Fluid (DEF) Indicator
Light — If Equipped
The Low Diesel Exhaust Fluid (DEF)
Indicator will illuminate if the vehicle
is low on Diesel Exhaust Fluid (DEF).
Refer to “Starting And Operating” for
further information.
Wait To Start Light — If Equipped
This indicator light will illuminate for
approximately two seconds when the
ignition is turned to the RUN position.
Its duration may be longer based on colder operating conditions. Vehicle will not
initiate start until telltale is no longer displayed.
Refer to “Starting The Engine” in “Starting And
Operating” for further information.
NOTE:
The “Wait To Start” telltale may not illuminate if
the intake manifold temperature is warm
enough.
Water In Fuel Indicator Light — If Equipped
The “Water In Fuel Indicator Light” will
illuminate when there is water
detected in the fuel filter. If this light
remains on, DO NOT start the vehicle
before you drain the water from the fuel filter to
prevent engine damage.
Refer to the “Draining Fuel/Water Separator
Filter” section in “Dealer Service” in “Servicing
And Maintenance” for further information.
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GETTING TO KNOW YOUR INSTRUMENT PANEL141
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 indi -
cator 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 depar -
ture occurs on the detected lane line.
Refer to “LaneSense — If Equipped” in “Starting
And Operating” for further information.
Blue Indicator Lights
High Beam Indicator Light
This indicator light will illuminate to
indicate that the high beam head -
lights are on. With the low beams acti -
vated, 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 emis -
sions, 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 govern -
ment 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
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142GETTING TO KNOW YOUR INSTRUMENT PANEL
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 diag-
nosis 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 emis
-sions control system. Failure to pass could
prevent vehicle registration.
For states that require an Inspection
and Maintenance (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 replacement. 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.
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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GETTING TO KNOW YOUR INSTRUMENT PANEL143
2. As soon as you cycle the ignition switch to
the ON position, you will see the “Malfunc -
tion 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 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 illuminated 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 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.
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230STARTING AND OPERATING
DIESEL EXHAUST BRAKE — ENGINE
BRAKING (IF EQUIPPED)
The purpose of the exhaust brake (engine
braking) feature is to supply negative (braking)
torque from the engine. Typically, the engine
braking is used for, but not limited to, vehicle
towing applications where vehicle braking can be achieved by the internal engine power,
thereby sparing the mechanical brakes of the
vehicle.
Benefits of the exhaust brake are:
Vehicle driving control.
Reduced brake fade.
Longer brake life.
Faster cab warm-up.
The exhaust brake feature will only function
when the driver toggles it on by pushing the
exhaust brake button until the “Exhaust Brake
Indicator” is illuminated. Normal (Full Strength)
exhaust brake mode is indicated by a yellow
“Exhaust Brake Indicator”.

Exhaust Brake Switch
Once the “Exhaust Brake Indicator” is illumi
-
nated and the vehicle is moving faster than
5 mph (8 km/h); the exhaust brake will auto -
matically operate when the driver removes
pressure from the accelerator pedal. Exhaust
braking is most effective when the engine RPM
is higher. The automatic transmission will down -
shift more aggressively in TOW/HAUL mode
when the exhaust brake is enabled to increase
brake performance.
Be sure the parking brake is fully disen -
gaged before driving; failure to do so can
lead to brake failure and a collision.
Always fully apply the parking brake when
leaving your vehicle or it may roll and cause
damage or injury. Also, be certain to leave
the transmission in PARK. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the Brake System Warning Light remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.
WARNING! (Continued)
WARNING!
Do not use the exhaust brake feature when
driving in icy or slippery conditions as the
increased engine braking can cause the rear
wheels to slide and the vehicle to swing
around with the possible loss of vehicle
control, which may cause an accident
possibly resulting in personal injury or death.
CAUTION!
Use of aftermarket exhaust brakes is not
recommended and could lead to engine
damage

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236STARTING AND OPERATING
Transmission Limp Home Mode
Transmission function is monitored electroni -
cally for abnormal conditions. If a condition is
detected that could result in transmission
damage, Transmission Limp Home Mode is acti -
vated. In this mode, the transmission may
operate only in certain gears, or may not shift at
all. Vehicle performance may be severely
degraded and the engine may stall. In some
situations, the transmission may not re-engage
if the engine is turned off and restarted. The
Malfunction Indicator Light (MIL) may be illumi -
nated. A message in the instrument cluster will
inform the driver of the more serious conditions,
and indicate what actions may be necessary.
In the event of a momentary problem, the trans -
mission can be reset to regain all forward gears
by performing the following steps:
NOTE:
In cases where the instrument cluster message
indicates the transmission may not re-engage
after engine shutdown, perform this procedure
only in a desired location (preferably, at an
authorized dealer).

1. Stop the vehicle.
2. Shift the transmission into PARK, if
possible. If not, shift the transmission to
NEUTRAL.
3. Push and hold the ignition switch until the engine turns off.
4. Wait approximately 30 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no longer detected, the trans -
mission will return to normal operation.
NOTE:
Even if the transmission can be reset, we
recommend that you visit an authorized dealer
at your earliest possible convenience. An autho -
rized dealer has diagnostic equipment to
assess the condition of your transmission.
If the transmission cannot be reset, authorized
dealer service is required.
Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control
allows the driver to limit the highest available
gear when the transmission is in DRIVE. For
example, if you set the transmission gear limit
to 4 (FOURTH gear), the transmission will not shift above FOURTH gear (except to prevent
engine overspeed), but will shift through the
lower gears normally.
You can switch between DRIVE and ERS mode
at any vehicle speed. When the transmission
gear selector is in DRIVE, the transmission will
operate automatically, shifting between all
available gears. Tapping the GEAR – switch (on
the steering wheel) will activate ERS mode,
display the current gear in the instrument
cluster, and set that gear as the top available
gear. Once in ERS mode, tapping the GEAR – or
GEAR + switch will change the top available
gear.

ERS Control

1 — GEAR + Switch
2 — GEAR – Switch

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STARTING AND OPERATING241
during very cold temperatures (-4°F [-20°C] or
below), operation may briefly be limited to third
gear only. During this condition, the ability of the
vehicle to accelerate under heavily loaded
conditions may be reduced. In all cases, normal
operation will resume once the transmission
temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electroni -
cally for abnormal conditions. If a condition is
detected that could result in transmission
damage, Transmission Limp Home Mode is acti -
vated. In this mode, the transmission remains
in fourth gear (for 68RFE transmission) or third
gear (for AS69RC transmission) regardless of
which forward gear is selected. If an
AS69RC-equipped truck enters Limp Home
Mode at highway speeds, it will initially engage
fifth gear, until the vehicle slows to a speed
where third gear can be engaged. PARK,
REVERSE, and NEUTRAL will continue to
operate. The Malfunction Indicator Light (MIL)
may be illuminated. Limp Home Mode allows
the vehicle to be driven to an authorized dealer
for service without damaging the transmission. In the event of a momentary problem, the trans
-
mission can be reset to regain all forward gears
by performing the following steps:

1. Stop the vehicle.

2. Shift the transmission into PARK.
3. Turn the ignition OFF.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no longer detected, the trans -
mission will return to normal operation.
NOTE:
Even if the transmission can be reset, we
recommend that you visit your authorized
dealer at your earliest possible convenience.
Your authorized dealer has diagnostic equip -
ment to assess the condition of your transmis -
sion.
If the transmission cannot be reset, authorized
dealer service is required.
Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control
allows the driver to limit the highest available gear when the transmission is in DRIVE. For
example, if you set the transmission gear limit
to 4 (FOURTH gear), the transmission will not
shift above FOURTH gear, but will shift through
the lower gears normally.
You can switch between DRIVE and ERS mode
at any vehicle speed. When the gear selector is
in the DRIVE position, the transmission will
operate automatically, shifting between all
available gears. Tapping the ERS (-) switch will
activate ERS mode, display the current gear in
the instrument cluster, and set that gear as the
top available gear. Once in ERS mode, tapping
the ERS (-) or (+) switch will change the top
available gear.

Electronic Range Select
1 — GEAR + Switch
2 — GEAR – Switch
5

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246STARTING AND OPERATING
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or illumi -
nates during driving, it means that the
four-wheel drive system is not functioning prop -
erly and that service is required.
NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning. This could
cause damage to driveline components.
When operating your vehicle in 4WD LOW, the
engine speed is approximately three times that
of the 2WD or 4WD HIGH positions at a given
road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).
Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and circum -
ference on each wheel. Any difference in tire
size can cause damage to the drivetrain. Because four-wheel drive provides improved
traction, there is a tendency to exceed safe
turning and stopping speeds. Do not go faster
than road conditions permit.
Shifting Procedure
NOTE:
If any of the requirements to select a new
transfer case position have not been met, the
transfer case will not shift. The position indi
-
cator light for the previous position will
remain on and the newly selected position
indicator light will continue to flash until all
the requirements for the selected position
have been met.
If all the requirements to select a new
transfer case position have been met, the
current position indicator light will turn off,
the selected position indicator light will flash
until the transfer case completes the shift.
When the shift is complete, the position indi -
cator light for the selected position will stop
flashing and remain on. 2WD To 4WD HIGH
Push the desired position on the 4WD control
switch to shift the transfercase. Shifts between
2WD and 4WD HIGH can be done with the
vehicle stopped or in motion. With the vehicle in
motion, the transfer case will engage/disen
-
gage faster if you momentarily release the
accelerator pedal after turning the control
switch. If the vehicle is stopped, the ignition
switch must be in the ON position with the
engine either running or off. This shift cannot be
completed if the ignition switch is in the ACC
position.
NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD HIGH if the front and/or
rear wheels are spinning (no traction). In this
situation, the selected position indicator light
will flash and the original position indicator light
will remain on. At this time, reduce speed and
stop spinning the wheels to complete the shift.
WARNING!
Always engage the parking brake when
powering down the vehicle if the “SVC 4WD
Warning Light” is illuminated. Not engaging
the parking brake may allow the vehicle to roll
which may cause personal injury or death.

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