tow RAM CHASSIS CAB 2021 Service Manual

STARTING AND OPERATING151

Electronic Range Select

To exit ERS mode, simply push and hold the ERS
(+) switch until the gear limit display disappears
from the instrument cluster. NOTE:
To select the proper gear position for maximum
deceleration (engine braking), simply push and
hold the ERS (-) switch. The transmission will
shift to the range from which the vehicle can
best be slowed down.
Overdrive Operation

The automatic transmission includes an
electronically controlled Overdrive (FIFTH and SIXTH
gears). The transmission will automatically shift into
Overdrive if the following conditions are present:

The gear selector is in the DRIVE position.
The transmission fluid has reached an
adequate temperature.
The engine coolant has reached an adequate
temperature.
Vehicle speed is sufficiently high.

The TOW/HAUL switch has not been activated.

The driver is not heavily pressing the accelerator.

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.
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.

CAUTION!
When using ERS for engine braking while
descending steep grades, be careful not to
overspeed the engine. Apply the brakes as
needed to prevent engine overspeed.4

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152STARTING AND OPERATING
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.
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.
AUXILIARY SWITCHES — IF EQUIPPED
There can be up to six auxiliary switches located
in the lower switch bank of the instrument panel
which can be used to power various electronic
devices and Power Take Off (PTO). If equipped,
it will take the place of the sixth auxiliary switch.
Connections to the switches are found under
the hood in the connectors attached to the
auxiliary Power Distribution Center.

You have the ability to configure the functionality of
the auxiliary switches via the instrument cluster
display. All switches can now be configured for
setting the switch type operation to latching or
momentary, power source of either battery or
ignition, and ability to hold last state across key
cycles.

NOTE:
Holding last state conditions are met when
switch type is set to latching and power source
is set to ignition.

For further information on using the auxiliary
switches, please refer to the Ram Body Builders
Guide by accessing
https://www.ramtrucks.com/
ram-commercial/body-builders-guide.html
and
choosing the appropriate links.

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.

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STARTING AND OPERATING153
(Continued)
FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with
either a manually shifted transfer case or an
electronically shifted transfer case.
ELECTRONICALLY SHIFTED TRANSFER
C
ASE (EIGHT SPEED TRANSMISSION) —
I
F EQUIPPED
This is an electronically shifted transfer case
and is operated by the 4WD Control Switch
(Transfer Case Switch), which is located on the
instrument panel.

Four-Position Transfer Case
This electronically shifted transfer case
provides four mode positions:
Two-Wheel Drive High Range (2WD)
Four-Wheel Drive High Range (4WD High)
Four-Wheel Drive Low Range (4WD Low)
N (Neutral)
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2WD
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry, hard
surfaced roads.
4WD High
Four-Wheel Drive High Range — This range
provides torque to the front driveshaft (engages
four-wheel drive) which allows front and rear
wheels to spin at the same speed. This provides
additional traction for loose, slippery road
surfaces only. 4WD Low

Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive. It maximizes
torque (increased torque over 4WD High) to the
front driveshaft, allowing front and rear wheels to
rotate at the same speed. This range provides
additional traction and maximum pulling power
for loose, slippery road surfaces only. Do not
exceed 25 mph (40 km/h) in this range.

N (Neutral)
N (Neutral) — This range disengages both the
front and rear driveshafts from the powertrain.
To be used for flat towing behind another
vehicle Ú
page 214.
WARNING!

You or others could be injured or killed if you
leave the vehicle unattended with the
transfer case in the N (NEUTRAL) position
without first fully engaging the parking brake.
The transfer case N (NEUTRAL) position
disengages both the front and rear drive
shaft 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.

4

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154STARTING AND OPERATING
This electronically shifted transfer case is
designed to be driven in the two-wheel drive
position (2WD) for normal street and highway
conditions on dry hard surfaced roads. Driving
the vehicle in two-wheel drive will have greater
fuel economy benefits as the front axle is not
engaged in two-wheel drive.
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 pushing the desired position on the
four-wheel drive control switch.
For specific shifting instructions Ú page 159.
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 in the
center of the four-wheel drive 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

Ú
page 214.

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 Ú page 159.
The “SVC 4WD Warning Light” monitors the
electronically shifted 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.

The transmission may not engage PARK if
the vehicle is moving. Always bring the
vehicle to a complete stop before shifting to
PARK, and verify that the transmission gear
position indicator solidly indicates PARK (P)
without blinking. Ensure that the vehicle is
completely stopped, and the PARK position
is properly indicated, before exiting the
vehicle.

WARNING! (Continued)

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STARTING AND OPERATING157
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2WD
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry, hard
surfaced roads.
4WD HIGH
Four-Wheel Drive High Range — This range
maximizes torque to the front driveshaft, forcing
the front and rear wheels to rotate at the same
speed. This range provides additional traction
for loose, slippery road surfaces only.
4WD LOW
Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive.
It maximizes torque to the front driveshaft,
forcing the front and rear wheels to rotate at the
same speed. This range provides additional
traction and maximum pulling power for loose,
slippery road surfaces only. Do not exceed
25 mph (40 km/h). N (Neutral)
N (Neutral) — This range disengages both the
front and rear driveshafts from the powertrain.
To be used for flat towing behind another
vehicle Ú
page 214.
This electronically shifted transfer case is
designed to be driven in the two-wheel drive
position (2WD) for normal street and highway
conditions on dry, hard surfaced roads. 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 four-wheel drive Control Switch
to the desired position.
For specific shifting instructions Ú
page 159.

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 four-wheel drive
Control Switch. The transfer case NEUTRAL posi -
tion is to be used for recreational towing only

Ú
page 214.

WARNING!

You or others could be injured or killed if you
leave the vehicle unattended with the transfer
case in the N (NEUTRAL) position without first
fully engaging the parking brake. The transfer
case N (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.

4

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160STARTING AND OPERATING
Alternate Procedure

1. Bring the vehicle to a complete stop.

2. With the ignition switch in the ON position
and the engine running, shift the
transmission into NEUTRAL.
3. Push the desired position on the transfer case control switch.
4. After the desired position indicator light is on (not flashing), shift the transmission
back into gear.
NOTE:
If Steps 1 or 2 of either the Preferred or Alter -
nate Procedure are not satisfied prior to
attempting the shift, then the desired posi -
tion indicator light will flash continuously
while the original position indicator light is
on, until all requirements have been met.
The ignition switch must be in the ON position
for a shift to take place and for the position
indicator lights to be operable. If the ignition
switch is not in the ON position, the shift will
not take place and no position indicator lights
will be on or flashing.
MANUALLY SHIFTED TRANSFER CASE —
I
F EQUIPPED
The transfer case provides four mode positions:
Two-Wheel Drive High Range (2H)
Four-Wheel Drive Lock High Range (4H)
N (Neutral)
Four-Wheel Drive Low Range (4L)
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2H
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry, hard
surfaced roads.
4H
Four-Wheel Drive Lock 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 both the
front and rear driveshafts from the powertrain.
To be used for flat towing behind another
vehicle Ú
page 214.
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).
This transfer case is intended to be driven in
the 2H position for normal street and highway
conditions such as dry, hard surfaced roads.
When additional traction is required, the 4H and
4L positions can be used to lock the front and
rear driveshafts together and force the front
and rear wheels to rotate at the same speed.
This is accomplished by simply moving the gear
selector to the desired positions once the
appropriate speed and gear requirements are
met Ú page 159.

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STARTING AND OPERATING167
(Continued)
Adaptive Cruise Control (ACC) Operation
The buttons on the right side of the steering
wheel operate the ACC system.
Adaptive Cruise Control Buttons
Does not always fully recognize
complex driving conditions, which can
result in wrong or missing distance
warnings.

Will bring the vehicle to a complete stop
while following a target vehicle and hold
the vehicle for approximately two seconds
in the stop position. At this point, there will
be an “ACC may cancel soon” chime and
warning to the driver. When ACC is
cancelled, the system will release the
brakes and the driver must take over
braking. The system can be resumed when
the target vehicle drives off by releasing
the brake and pushing the resume button
on the steering wheel.

WARNING! (Continued)
You should switch off the ACC system:
When driving in fog, heavy rain, heavy
snow, sleet, heavy traffic, and complex
driving situations (i.e., in highway construc -
tion zones).
When entering a turn lane or highway off
ramp; when driving on roads that are
winding, icy, snow-covered, slippery, or
have steep uphill or downhill slopes.
When towing a trailer up or down steep
slopes.
When circumstances do not allow safe
driving at a constant speed.
WARNING! (Continued)
1 — Adaptive Cruise Control On/Off Button
2 — Fixed Speed Cruise Control On/Off Button
3 — CANCEL
4 — Distance Button
5 — RES (+)
6 — SET (-)
4

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STARTING AND OPERATING175
Service ACC/FCW Warning

If the system turns off, and the instrument cluster
displays “ACC/FCW Unavailable Service
Required” or “Cruise/FCW Unavailable Service
Required”, there may be an internal system fault
or a temporary malfunction that limits ACC
functionality. Although the vehicle is still drivable
under normal conditions, ACC will be temporarily
unavailable. If this occurs, try activating ACC
again later, following an ignition cycle. If the
problem persists, see an authorized dealer.

Precautions While Driving With ACC
NOTE:
Aftermarket add-ons such as snow plows, lift
kits, and brush/grille bars can hinder module
performance. Ensure the radar/camera has
no obstructions in the field of view.
Height modifications can limit module perfor -
mance and functionality.
Do not put stickers or easy passes over the
camera/radar field of view.
Any modifications to the vehicle that may
obstruct the field of view of the radar/camera
are not recommended.
In certain driving situations, ACC may have
detection issues. In these cases, ACC may
brake late or unexpectedly. The driver needs
to stay alert and may need to intervene.
The following are examples of these types of
situations:
Towing A Trailer
ACC while towing a trailer is recommended only
with an Integrated Trailer Brake Controller.
Aftermarket trailer brake controllers will not
activate the trailer brakes when ACC is braking. Offset Driving
ACC may not detect a vehicle in the same lane
that is offset from your direct line of travel, or a
vehicle merging in from a side lane. There may
not be sufficient distance to the vehicle ahead.
The offset vehicle may move in and out of the
line of travel, which can cause your vehicle to
brake or accelerate unexpectedly.

Offset Driving Condition Example

4

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STARTING AND OPERATING183
LANESENSE — IF EQUIPPED
LANESENSE OPERATION
The LaneSense system is operational at speeds
above 37 mph (60 km/h) and below 112 mph
(180 km/h). It uses a forward looking camera to
detect lane markings and measure vehicle
position within the lane boundaries.
When both lane markings are detected and the
driver drifts out of the lane (no turn signal has
been applied) OR the driver departs the lane on
the opposite side of the applied turn signal (if the left turn signal is applied and the vehicle
departs to the right), the LaneSense system
provides a haptic warning in the form of torque
applied to the steering wheel, as well as a visual
warning in the instrument cluster display to
prompt the driver to remain within the lane
boundaries.
The driver may manually override the haptic
warning by applying torque into the steering
wheel at any time.
When only a single lane marking is detected
and the driver drifts across that lane marking
(no turn signal applied), the LaneSense system
provides a visual warning through the
instrument cluster display to prompt the driver
to remain within the lane.
When only a single lane marking is detected, a
haptic (torque) warning will not be provided.
NOTE:
When operating conditions have been met, the
LaneSense system will monitor if the driver’s
hands are on the steering wheel and provide
an audible and visual warning to the driver if
removed. The system will cancel if the driver
does not return their hands to the wheel.
WARNING!

Drivers must be careful when backing up
even when using ParkSense. Always check
carefully behind your vehicle, look behind
you, and be sure to check for pedestrians,
animals, other vehicles, obstructions, and
blind spots before backing up. You are
responsible for safety and must continue to
pay attention to your surroundings. Failure to
do so can result in serious injury or death.

Before using ParkSense, it is strongly
recommended that the ball mount and
hitch ball assembly be disconnected from
the vehicle when the vehicle is not used for
towing. Failure to do so can result in injury
or damage to vehicles or obstacles
because the hitch ball will be much closer
to the obstacle than the rear fascia when
the vehicle sounds the continuous tone.
Also, the sensors could detect the ball
mount and hitch ball assembly, depending
on its size and shape, giving a false indica
-
tion that an obstacle is behind the vehicle.
CAUTION!

ParkSense is only a parking aid and it is
unable to recognize every obstacle, including
small obstacles. Parking curbs might be
temporarily detected or not detected at all.
Obstacles located above or below the
sensors will not be detected when they are in
close proximity.

The vehicle must be driven slowly when
using ParkSense in order to be able to stop
in time when an obstacle is detected. It is
recommended that the driver looks over
his/her shoulder when using ParkSense.4

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STARTING AND OPERATING191
Cargo Camera
Pressing the Cargo Camera soft key
will provide a full screen view of the
cargo area.
NOTE:

If the Cargo Camera view was selected through
the Surround View screen, exiting out of the
Cargo Camera screen will return to the Surround
View screen. If the Cargo Camera was manually
activated through the Controls menu of the
Uconnect display, exiting out of the display
screen will return to the Controls menu.

Trailer Reverse Guidance
Pressing the Trailer Reverse Guidance
soft key will provide a full screen view of
the cargo area and trailer.

Pressing the Left & Right Tow Mirror
Split Screen View button within the
Trailer Reverse Guidance screen will
display a split screen to allow the
driver to see both sides of the trailer at the
same time. This view allows the driver to pan
left/right to better frame the trailer in the image. NOTE:
Trailer Reverse Guidance can only be selected
through the Surround View screen; exiting out of
the Trailer Reverse Guidance screen will return
to the Surround View screen.
Zoom View

When the Rear View image is being displayed,
and the vehicle speed is below 8 mph (13 km/h)
while in any gear, Zoom View is available.
By pressing the “magnifying glass” icon in the
upper left of the display screen, the image will
zoom in to four times the standard view. Pressing
the icon a second time will return the view to the
standard Rear View.

When Zoom View is selected while the vehicle is
in REVERSE, then shifted to DRIVE, the camera
delay view will display the standard Back Up
Camera view. If the vehicle is then returned to
REVERSE gear from DRIVE, the Zoom View
selection will automatically resume.
Shifting to NEUTRAL from any gear will maintain
the selected view (Zoom or Standard) as long as
the vehicle is below 8 mph (13 km/h).
If the vehicle is in PARK, Zoom View is available
until the gear selector is placed in DRIVE or
REVERSE and speeds are at or above 8 mph
(13 km/h).NOTE:
If the vehicle is in DRIVE, NEUTRAL, or
REVERSE, and speed is greater than or equal
to 8 mph (13 km/h), Zoom View is unavail
-
able and the icon will appear gray.
While in Zoom View, the guidelines will not be
visible.
Deactivation
The system is deactivated in the following
conditions if it was activated automatically:
When the vehicle is shifted out of REVERSE
(with camera delay turned on), the camera
image will continue to be displayed for up
to 10 seconds unless the vehicle speed
exceeds 8 mph (13 km/h), the vehicle is
shifted into PARK or the ignition is placed in
the OFF position. There is a touchscreen
button “X” to disable the display of the
camera image.
When the vehicle is shifted out of REVERSE
(with camera delay turned off), the Surround
View Camera mode is exited and the last
known screen appears again.
4

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