warning light Ram 3500 2020 Repair Manual

STARTING AND OPERATING231
(Continued)
NOTE:
Light duty operation such as light trailer towing
or no load operation will extend the time before
the engine is at full efficiency. Reduced fuel
economy and power may be seen at this time.
For additional vehicle break-in requirements,
refer to “Trailer Towing” in “Starting And
Operating” of the Owners Manual.
Because of the construction of the Cummins®
Turbo Diesel engine, engine run-in is enhanced
by loaded operating conditions which allow the
engine parts to achieve final finish and fit during
the first 6,000 miles (10,000 km).
PARKING BRAKE
Before leaving the vehicle, make sure that the
parking brake is fully applied. Also, be certain to
leave the transmission in PARK.
The foot-operated parking brake is located
below the lower left corner of the instrument
panel. To apply the park brake, firmly push the
park brake pedal fully. To release the parking
brake, pull the parking brake release handle.
Parking Brake Release

When the parking brake is applied with the
ignition switch ON, the “Brake Warning Light” in
the instrument cluster will illuminate.
NOTE:When the parking brake is applied and the
transmission is placed in gear, the “Brake
Warning Light” will flash. If vehicle speed is
detected, a chime will sound to alert the
driver. Fully release the parking brake before
attempting to move the vehicle.
This light only shows that the parking brake is
applied. It does not show the degree of brake
application. When parking on a hill, it is important to turn the
front wheels toward the curb on a downhill
grade and away from the curb on an uphill
grade. Apply the parking brake before placing
the gear selector in PARK, otherwise the load on
the transmission locking mechanism may make
it difficult to move the gear selector out of PARK.
The parking brake should always be applied
whenever the driver is not in the vehicle.
WARNING!
Never use the PARK position as a substi
-
tute for the parking brake. Always apply the
parking brake fully when parked to guard
against vehicle movement and possible
injury or damage.
Never leave children alone in a vehicle, or
with access to an unlocked vehicle. Leaving
unattended children in a vehicle is
dangerous for a number of reasons. A child
or others could be seriously or fatally
injured.
5

20_DJD2_OM_EN_USC_t.book Page 231

232STARTING 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
illuminated and the vehicle is moving faster
than 5 mph (8 km/h); the exhaust brake will
automatically 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
downshift more aggressively in TOW/HAUL
mode when the exhaust brake is enabled to
increase brake performance.
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil-
dren, and do not leave a vehicle equipped
with Keyless Enter-N-Go in the ACC or ON/
RUN mode. A child could operate power
windows, other controls, or move the
vehicle.
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)

20_DJD2_OM_EN_USC_t.book Page 232

STARTING AND OPERATING239
gear. Once in ERS mode, tapping the GEAR – or
GEAR + switch will change the top available
gear.

ERS Control

To exit ERS mode, simply push and hold the
GEAR + switch until the gear limit display
disappears from the instrument cluster.When to Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer,
carrying a heavy load, etc., and frequent
transmission shifting occurs, push the TOW/
HAUL switch to activate TOW/HAUL mode. This
will improve performance and reduce the
potential for transmission overheating or failure
due to excessive shifting.

TOW/HAUL Switch

The “TOW/HAUL Indicator Light” will illuminate
in the instrument cluster to indicate that TOW/
HAUL mode has been activated. Pushing the
switch a second time restores normal
operation. Normal operation is always the
default at engine start-up. If TOW/HAUL mode is
desired, the switch must be pushed each time
the engine is started.
SIX-SPEED AUTOMATIC TRANSMISSION
— I
F EQUIPPED
Pickup models may use either AISIN (AS69RC
HD) transmission, or the 68RFE transmission
(which has no PTO access cover).
The transmission gear position display (located
in the instrument cluster) indicates the
transmission gear range. The gear selector is
mounted on the right side of the steering
column. You must press the brake pedal to
move the gear selector out of PARK; refer to
“Brake/Transmission Shift Interlock System” in
this section. To drive, move the gear selector
from PARK or NEUTRAL to the DRIVE position.
Pull the gear selector toward you when shifting
into REVERSE or PARK, or when shifting out of
PARK.
1 — GEAR + Switch
2 — GEAR – Switch
WARNING!
Do not downshift for additional engine
braking on a slippery surface. The drive
wheels could lose their grip and the vehicle
could skid, causing a collision or personal
injury.
WARNING!
Do not use the “TOW/HAUL” feature when
driving in icy or slippery conditions. 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.
5

20_DJD2_OM_EN_USC_t.book Page 239

242STARTING AND OPERATING
NEUTRAL (N)
Use this range when the vehicle is standing for
prolonged periods with the engine running. The
engine may be started in this range. Apply the
parking brake and shift the transmission into
PARK if you must exit the vehicle. DRIVE (D)
This range should be used for most city and
highway driving. It provides the smoothest
upshifts and downshifts, and the best fuel
economy. The transmission automatically
upshifts through underdrive first, second, and
third gears, direct fourth gear and overdrive fifth
and sixth gears. The DRIVE position provides
optimum driving characteristics under all
normal operating conditions.
When frequent transmission shifting occurs
(such as when operating the vehicle under
heavy loading conditions, in hilly terrain,
traveling into strong head winds, or while towing
a heavy trailer), use the Electronic Range Select
(ERS) shift control refer to “Electronic Range
Select (ERS) Operation” in this section for
further information to select a lower gear range.
Under these conditions, using a lower gear
range will improve performance and extend
transmission life by reducing excessive shifting
and heat buildup.If the transmission temperature exceeds
normal operating limits, the powertrain
controller will modify the transmission shift
schedule and expand the range of torque
converter clutch engagement. This is done to
prevent transmission damage due to
overheating.
If the transmission becomes extremely hot or is
in danger of overheating, the “Transmission
Temperature Warning Light” may illuminate and
the transmission may operate differently until
the transmission cools down.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer
up a steep grade, or in stop-and-go traffic)
during hot weather. In these conditions, torque
converter slip can impose a significant addi
-
tional heat load on the cooling system. Down -
shifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to
NEUTRAL (when stopped in heavy traffic) can
help to reduce this excess heat generation.
WARNING!
Do not coast in NEUTRAL and never turn off
the ignition to coast down a hill. These are
unsafe practices that limit your response to
changing traffic or road conditions. You might
lose control of the vehicle and have a
collision.
CAUTION!
Towing the vehicle, coasting, or driving for any
other reason with the transmission in
NEUTRAL can cause severe transmission
damage. Refer to “Recreational Towing” in
“Starting And Operating” and “Towing A
Disabled Vehicle” in “In Case Of Emergency”
for further information.

20_DJD2_OM_EN_USC_t.book Page 242

STARTING AND OPERATING245
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer,
carrying a heavy load, etc., and frequent
transmission shifting occurs, push the TOW/
HAUL switch to activate TOW/HAUL mode. This
will improve performance and reduce the
potential for transmission overheating or failure
due to excessive shifting. When operating in
TOW/HAUL mode, transmission upshifts are
delayed, and the transmission will
automatically downshift (for engine braking)
when the throttle is closed and/or during steady
braking maneuvers.

TOW/HAUL Switch
The “TOW/HAUL Indicator Light” will illuminate
in the instrument cluster to indicate that TOW/
HAUL mode has been activated. Pushing the
switch a second time restores normal
operation. Normal operation is always the
default at engine start-up. If TOW/HAUL mode is
desired, the switch must be pushed each time
the engine is started.
Torque Converter Clutch
A feature designed to improve fuel economy
has been included in the automatic
transmission on your vehicle. A clutch within the
torque converter engages automatically at
calibrated speeds. This may result in a slightly
different feeling or response during normal operation in the upper gears. When the vehicle
speed drops or during some accelerations, the
clutch automatically disengages.
NOTE:
The torque converter clutch will not engage,
until the transmission fluid and engine
coolant are warm [usually after 1 to 3 miles
(2 to 5 km) of driving]. Because engine speed
is higher when the torque converter clutch is
not engaged, it may seem as if the transmis
-
sion is not shifting properly when cold. This is
normal. Using the Electronic Range Select
(ERS) shift control, when the transmission is
sufficiently warm, will demonstrate that the
transmission is able to shift into and out of
Overdrive.
If the vehicle has not been driven for several
days, the first few seconds of operation after
shifting the transmission into gear may seem
sluggish. This is due to the fluid partially
draining from the torque converter into the
transmission. This condition is normal and
will not cause damage to the transmission.
The torque converter will refill within five
seconds after starting the engine.
WARNING!
Do not use the “TOW/HAUL” feature when
driving in icy or slippery conditions. 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.
5

20_DJD2_OM_EN_USC_t.book Page 245

248STARTING AND OPERATING
NOTE:
The transfer case NEUTRAL button is located in
the center of the 4WD Control Switch and is
pushed by using a ballpoint pen or similar
object. The transfer case NEUTRAL position is to
be used for recreational towing only. Refer to
“Recreational Towing” in “Starting And Oper -
ating” for further information.
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(4WD HIGH and 4WD LOW) are located in the
instrument cluster and indicate the current and
desired transfer case selection. When you
select a different transfer case position, the
indicator lights will do the following:
If All Of The Following Shift Conditions Are Met:

1. The current position indicator light will turn off.

2. The selected position indicator light will flash until the transfer case completes the
shift.
3. When the shift is complete, the indicator light for the selected position will stop
flashing and remain on. If One Or More Of The Following Shift Conditions
Are Not Met:

1. The indicator light for the current position
will remain on.

2. The newly selected position indicator light will continue to flash.
3. The transfer case will not shift.
NOTE:

Before retrying a selection, make certain that all
the necessary requirements for selecting a new
transfer case position have been met. To retry the
selection, push the current position, wait five
seconds, and retry selection. To find the shift
requirements, refer to the “Shifting Procedure”
for your transfer case, located in this section.
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or
illuminates during driving, it means that the
four-wheel drive system is not functioning
properly 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
circumference 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

20_DJD2_OM_EN_USC_t.book Page 248

STARTING AND OPERATING251
When additional traction is required, the
transfer case 4WD HIGH and 4WD LOW
positions can be used to maximize torque to the
front driveshaft, forcing the front and rear
wheels to rotate at the same speed. This is
accomplished by rotating the 4WD Control
Switch to the desired position.
Refer to “Shifting Procedure” in this section for
specific shifting instructions.
The 4WD HIGH and 4WD LOW positions are
designed for loose, slippery road surfaces only.
Driving in the 4WD HIGH and 4WD LOW
positions on dry hard surfaced roads may cause
increased tire wear and damage to the driveline
components.
NOTE:
The transfer case NEUTRAL button is located on
the lower left hand corner of the 4WD Control
Switch. The transfer case NEUTRAL position is
to be used for recreational towing only. Refer to
“Recreational Towing” in “Starting And Oper -
ating” for further information. Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(4WD and 4LOW) are located in the instrument
cluster and indicate the current and desired
transfer case selection. When you select a
different transfer case position, the indicator
lights will do the following:
If All Of The Following Shift Conditions Are Met:


1. The current position indicator light will turn OFF.

2. The selected position indicator light will flash until the transfer case completes the
shift.
3. When the shift is complete, the indicator light for the selected position will stop
flashing and remain ON.
If One Or More Of The Following Shift Conditions
Are Not Met:

1. The indicator light for the current position will remain ON.

2. The newly selected position indicator light will continue to flash.
3. The transfer case will not shift. NOTE:
Before retrying a selection, make certain that all
the necessary requirements for selecting a new
transfer case position have been met. To retry
the selection, turn the control switch back to the
current position, wait five seconds, and retry
selection. To find the shift requirements, refer
to the "Shifting Procedure" for your transfer
case, located in this section.
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or
illuminates during driving, it means that the
four-wheel drive system is not functioning
properly and that service is required.
NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning, as this can
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).
5

20_DJD2_OM_EN_USC_t.book Page 251

254STARTING AND OPERATING
met. Refer to “Shifting Procedure – Manually
Shifted Transfer Case” in this section for further
information.
The 4H and 4L positions are intended for loose,
slippery road surfaces only. Driving in the 4H
and 4L positions on dry, hard surfaced roads
may cause increased tire wear and damage to
the driveline components.
The “Transfer Case Position Indicator Light” in
the instrument cluster will alert the driver that
the vehicle is in four-wheel drive and that the
front and rear driveshafts are locked together.
This light will illuminate when the transfer case
is shifted into either the 4H or 4L position. There
is no light for the 2H or NEUTRAL positions on
some models.
When operating your vehicle in 4L, the engine
speed is approximately three times that of the
2H or 4H 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
circumference on each wheel. Any difference
will adversely affect shifting and can cause
damage to the drivetrain. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning, as this can
cause damage to driveline components.
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.
NOTE:
Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or
uneven tire pressures, excessive vehicle
loading, or cold temperatures.Two-Wheel Drive High Range (2H)
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry hard
surfaced roads.
Four-Wheel Drive High Range (4H)
Four-Wheel Drive High Range — This range locks
the front and rear driveshafts together forcing
the front and rear wheels to rotate at the same
speed. Additional traction for loose, slippery
road surfaces only.
N (Neutral)
N (Neutral) — This range disengages the front
and rear driveshafts from the powertrain. To be
used for flat towing behind another vehicle.
Refer to “Recreational Towing” in “Starting And
Operating” for further information.
Four-Wheel Drive Low Range (4L)
Four-Wheel Drive Low Range — This range locks
the front and rear driveshafts together forcing
the front and rear wheels to rotate at the same
speed. Additional traction and maximum pulling
power for loose, slippery road surfaces only. Do
not exceed 25 mph (40 km/h).
WARNING!
You or others could be injured or killed if you
leave the vehicle unattended with the transfer
case in the NEUTRAL position without first
fully engaging the parking brake. The transfer
case NEUTRAL position disengages both the
front and rear drive shafts from the
powertrain and will allow the vehicle to roll,
even if the transmission is in PARK. The
parking brake should always be applied when
the driver is not in the vehicle.

20_DJD2_OM_EN_USC_t.book Page 254

STARTING AND OPERATING259
The locking axles are controlled by the axle lock
buttons.
Under normal driving conditions, the vehicle
should be left in the AXLE UNLOCK position.
NOTE:
Even when the axles are in the AXLE UNLOCK
position, the limited slip differential in the rear
axle still provides torque biasing capability for
moderate low traction environments.
During the command to lock the axle, the
indicator light will flash until the axle is locked.
After the lock command has been successfully
executed, the light will remain on solid. To lock the rear axle, place the vehicle in 4WD
LOW, 4WD HIGH or 2WD. Refer to “Four Wheel
Drive Operation” in “Starting And Operating” for
further information. Push the REAR LOCK
button while traveling less than 10 mph
(16 km/h). The REAR LOCK indicator light will
remain on when the rear axle is locked.
NOTE:
Left to right wheel speed difference may be
necessary to allow the axle to fully lock. If the
indicator light is flashing after placing the
vehicle in the REAR LOCK or FRONT/REAR LOCK
position, drive the vehicle in a turn or on loose
gravel to expedite the locking action.
To lock the front axle, push the FRONT/REAR
LOCK button while traveling less than 10 mph
(16 km/h) in 4WD LOW. The FRONT/REAR
LOCK indicator light will be solid when the front
axle is locked.
NOTE:
The rear axle must be locked before the front
axle will lock.
When both the axles are locked, to unlock the
front axle, push the REAR LOCK button while in
4WD LOW. The FRONT/REAR LOCK indicator
light will go out when the axle is unlocked.
NOTE:
The axle lockers could be torque locked due to
side to side loads on the axle. Driving slowly
while turning the steering wheel from a left
hand turn to a right hand turn or driving in
REVERSE for a short distance may be required
to release the torque lock and unlock the axles.
To unlock the rear axle, push the AXLE UNLOCK
button. The REAR LOCK indicator light will go
out when the rear axle is unlocked.
Do not try to lock the rear axle if the vehicle
is stuck and the tires are spinning. You can
damage drivetrain components. Lock the
rear axle before attempting situations or
navigating terrain, which could possibly
cause the vehicle to become stuck.
CAUTION!
(Continued)
WARNING!
Do not use the locked axle position for normal
driving. A locked front axle is intended for
off-road driving only. Locking the front axle
during on-road driving will reduce the steering
ability. This could cause a collision and you
may be seriously injured.
5

20_DJD2_OM_EN_USC_t.book Page 259

260STARTING AND OPERATING
STABILIZER/SWAY BAR SYSTEM — POWER
WAGON ONLY
Your vehicle is equipped with an electronic
disconnecting stabilizer/sway bar. This system
allows greater front suspension travel in
off-road situations.
Due to the use of taller springs, this vehicle has
an increased ride height of approximately
1.9 inches (48.3 mm) in the front and
1.5 inches (38.1 mm) in the rear. A major advantage to increasing ride height is the
positive effect it has on approach/departure
and break over angles.
This system is controlled by the electronic
control sway bar switch located below the
instrument panel.

Sway Bar Disconnect Button
Push the SWAY BAR switch to activate the
system. Push the switch again to deactivate the
system. The “Sway Bar Indicator Light” (located
in the instrument cluster) will illuminate when
the bar is disconnected. The “Sway Bar
Indicator Light” will flash during activation
transition, or when activation conditions are not
met. The stabilizer/sway bar should remain in
on-road mode during normal driving conditions.
To disconnect the stabilizer/sway bar, shift to
either 4WD HIGH or 4WD LOW and push the
SWAY BAR button to obtain the Off-Road
position. Refer to “Four Wheel Drive Operation”
in “Starting And Operating” for further
information. The “Sway Bar Indicator Light” will
flash until the stabilizer/sway bar has been fully
disconnected.
NOTE:
The stabilizer/sway bar may be torque locked
due to left and right suspension height differ
-
ences. This condition is due to driving surface
differences or vehicle loading. In order for the
stabilizer/sway bar to disconnect/reconnect,
the right and left halves of the bar must be
aligned. This alignment may require that the
vehicle be driven onto level ground or rocked
from side to side.
To return to the On-Road mode, push the SWAY
BAR button again.
WARNING!
Do not disconnect the stabilizer bar and drive
on hard surfaced roads or at speeds above
18 mph (29 km/h), you may lose control of
the vehicle, which could result in serious
injury or death. The front stabilizer bar
enhances vehicle stability and assists in
maintaining control of the vehicle. The system
monitors vehicle speed and will attempt to
reconnect the stabilizer bar at speeds over
18 mph (29 km/h). This is indicated by a
flashing off road light and solid on road light.
Once vehicle speed is reduced below 14 mph
(22 km/h), the system will attempt to return
to the Off-Road mode.

20_DJD2_OM_EN_USC_t.book Page 260