service RAM CHASSIS CAB 2021 Owner's Guide

STARTING AND OPERATING145
Transmission Limp Home Mode
Transmission function is monitored
electronically for abnormal conditions.
If a condition is detected that could result in
transmission damage, Transmission Limp
Home Mode is activated. 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 illuminated. 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
transmission 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
transmission 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 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 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.

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150STARTING AND OPERATING
On trucks with AS66RC or AS69RC
transmission, FIFTH and SIXTH gears may
be inhibited briefly on cold starts below
41°F (5°C), and 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
electronically for abnormal conditions.
If a condition is detected that could result in
transmission damage, Transmission Limp
Home Mode is activated. In this mode, the
transmission remains in THIRD gear regardless
of which forward gear is selected. If an
AS66RC/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
transmission 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 to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.

6. Shift into the desired gear range. If the
problem is no longer detected, the
transmission 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 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 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
(-) or (+) will change the top available gear.

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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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158STARTING AND OPERATING
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(four-wheel drive 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, turn the control switch back to 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. 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 two-wheel drive 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.
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.

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STARTING AND OPERATING163
POWER TAKE OFF (PTO) OPERATION — IF
EQUIPPED

This vehicle when equipped with PTO Prep and
the AS66RC/AS69RC automatic six-speed, will
allow for an aftermarket upfit with a transmission
driven PTO (power take off). The customer will
have the ability to operate the PTO in either
a “stationary”, “mobile” or “remote” mode.
The vehicles will be factory set to the “stationary”
mode. To select a different mode, or to change
any other PTO setting, you will need to enter the
commercial vehicle menu on the instrument
cluster screen. Details of the PTO selection
modes and further PTO information is available
at the Ram Truck Bodybuilders web site:
https://
www.ramtrucks.com/ram-commercial/
body-builders-guide.html
POWER STEERING
HYDRAULIC POWER STEERING
The standard power steering system will give
you good vehicle response and increased ease
of maneuverability in tight spaces. The system
will provide mechanical steering capability if
power assist is lost.

If for some reason the power assist is interrupted,
it will still be possible to steer your vehicle. Under
these conditions, you will observe a substantial
increase in steering effort, especially at very low
vehicle speeds and during parking maneuvers.

NOTE:
Increased noise levels at the end of the
steering wheel travel are considered normal
and do not indicate that there is a problem
with the power steering system.
Upon initial start-up in cold weather, the
power steering pump may make noise for a
short amount of time. This is due to the cold,
thick fluid in the steering system. This noise
should be considered normal, and it does not
in any way damage the steering system.
Power Steering Fluid Check
Checking the power steering fluid level at a
defined service interval is not required. The fluid
should only be checked if a leak is suspected,
abnormal noises are apparent, and/or the
system is not functioning as anticipated. Check
fluid level when the engine is cold and off.
Coordinate inspection efforts through an
authorized dealer.
CAUTION!
Prolonged operation of the steering system
at the end of the steering wheel travel will
increase the steering fluid temperature and it
should be avoided when possible. Damage to
the power steering pump may occur.
WARNING!
Fluid level should be checked on a level
surface and with the engine off to prevent
injury from moving parts and to ensure
accurate fluid level reading. Do not overfill.
Use only manufacturer's recommended
power steering fluid.
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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 OPERATING181
NOTE:
ParkSense will reduce the volume of the radio,
if on, when the system is sounding an audio
tone.
Front Park Assist Audible Alerts
ParkSense will turn off the Front Park Assist
audible alert (chime) after approximately three
seconds when an obstacle has been detected,
the vehicle is stationary, and brake pedal is
applied. Adjustable Chime Volume Settings
The Front and Rear chime volume settings are
programmable through the Uconnect system
Ú
page 228.
ENABLING AND DISABLING PARKSENSE
Front ParkSense can be enabled and
disabled with the Front ParkSense
switch.
Rear ParkSense can be enabled and disabled
with the Rear ParkSense switch.
When the gear selector is moved to REVERSE
and the Front or Rear system is disabled, the
instrument cluster display will show a vehicle graphic with an “Off” message overlay over the
system that is off (Front or Rear system). This
vehicle graphic will be displayed for as long as
the vehicle is in REVERSE.
The Front or Rear ParkSense switch LED will be
on when Front or Rear ParkSense is disabled or
requires service. The Front or Rear ParkSense
switch LED will be off when the Front or Rear
system is enabled. If the Front or Rear
ParkSense switch is pushed, and the system
requires service, the Front or Rear ParkSense
switch LED will blink momentarily, and then the
LED will be on.
WARNING ALERTS FOR FRONT
Front Distance
(inches/cm) Greater than 47 inches
(120 cm) 47-39 inches
(120-100 cm) 39-25 inches
(100-65 cm) 25-12 inches
(65-30 cm) Less than 12 inches
(30 cm)
Audible Alert Chime NoneNoneNone FastContinuous
Arcs-Left NoneNoneNone3rd Flashing 4th Flashing
Arcs-Center None1st Solid2nd Flashing 3rd Flashing4th Flashing
Arcs-Right NoneNoneNone3rd Flashing 4th Flashing
Radio Volume Reduced No
NoNo Yes Yes
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182STARTING AND OPERATING
SERVICE THE PARKSENSE PARK ASSIST
S
YSTEM
During vehicle start up, when the Front/Rear
ParkSense System has detected a faulted
condition, the instrument cluster display will
show the "Front/Rear ParkSense Unavailable
Service Required" or the "Front/Rear
ParkSense Unavailable Wipe Sensors"
message.
When the gear selector is moved into REVERSE,
a vehicle graphic will show in the instrument
cluster display, along with the display overlay
“Wipe Sensors.” If the system needs service,
the display overlay will read “Service.” Under
this condition, ParkSense will not operate.
If "Front/Rear ParkSense Unavailable Wipe
Sensors" appears in the instrument cluster
display make sure the outer surface and the
underside of the rear fascia/bumper is clean
and clear of snow, ice, mud, dirt or other
obstruction, and then cycle the ignition. If the
message continues to appear, see an
authorized dealer. If "Front/Rear ParkSense Unavailable Service
Required" appears in the instrument cluster
display, see an authorized dealer.CLEANING THE PARKSENSE SYSTEM
Clean the ParkSense sensors with water, car
wash soap and a soft cloth. Do not use rough or
hard cloths. Do not scratch or poke the sensors.
Otherwise, you could damage the sensors.
PARKSENSE SYSTEM USAGE
P
RECAUTIONS
NOTE:
Ensure that the front and rear bumpers are
free of snow, ice, mud, dirt and debris to keep
the ParkSense system operating properly.

Jackhammers, large trucks, and other vibrations
could affect the performance of ParkSense.
When you move the gear selector to the
REVERSE position and Front or Rear ParkSense
is turned off, the instrument cluster display will
show "Off" on the vehicle graphic arcs. This
vehicle graphic will be displayed for as long as
the vehicle is in REVERSE.

ParkSense, when on, will reduce the volume
of the radio when it is sounding a tone.
Clean the ParkSense sensors regularly,
taking care not to scratch or damage them.
The sensors must not be covered with ice,
snow, slush, mud, dirt or debris. Failure to do
so can result in the system not working prop -
erly. The ParkSense system might not detect
an obstacle behind or in front of the fascia/
bumper, or it could provide a false indication
that an obstacle is behind or in front of the
fascia/bumper.
Use the ParkSense switch to turn the Park -
Sense system off if obstacles such as bicycle
carriers, trailer hitches, etc. are placed within
18 inches (45 cm) from the rear fascia/
bumper. Failure to do so can result in the
system misinterpreting a close obstacle as a
sensor problem, causing the “Front/Rear
ParkSense Unavailable Service Required”
message to be appear in the instrument
cluster display.

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198STARTING AND OPERATING
(Continued)
NOTE:
The DEF gauge may take up to five seconds
to update after adding a gallon or more of
Diesel Exhaust Fluid (DEF) to the DEF tank.
If you have a fault related to the DEF system,
the gauge may not update to the new level.
See an authorized dealer for service.
The DEF gauge may also not immediately
update after a refill if the temperature of the
DEF fluid is below 39°F (4°C). The DEF tank
heater will possibly warm up the DEF fluid
and allow the gauge to update after a period
of run time. Under very cold conditions, it is
possible that the gauge may not reflect the
new fill level for several drives.
At 40°F (4°C) you could see some increase
in the DEF gauge due to the tank thawing.
The gauge and level sensor are working prop-
erly and is just updating with proper thawed
DEF.
Excessive overfilling of the DEF tank can
result in a MIL lamp/fault code and inaccu -
rate level readings. Refilling With Nozzles
You can fill up at any DEF distributor.
Proceed as follows:
Insert the DEF nozzle in the filler, start
refilling and stop refilling at the first shut-off
(the shut-off indicates that the DEF tank is
full). DO NOT proceed with the refilling, to
prevent spillage of DEF.
Extract the nozzle.
Refilling With Containers
Proceed as follows:
Check the expiration date.
Read the advice for use on the label before
pouring the content of the bottle into the DEF
tank.
After the indication appears on the instru -
ment panel display Ú page 90 fill the DEF
tank with no more than 6 Gallons (22 liters).
CAUTION!
To avoid DEF spillage, and possible
damage to the DEF tank from overfilling, do
not “top off” the DEF tank after filling.
DO NOT OVERFILL. DEF will freeze below
12ºF (-11ºC). The DEF system is designed
to work in temperatures below the DEF
freezing point, however, if the tank is over -
filled and freezes, the system could be
damaged.
When DEF is spilled, clean the area imme -
diately with water and use an absorbent
material to soak up the spills on the ground.
Do not attempt to start your engine if DEF is
accidentally added to the diesel fuel tank
as it can result in severe damage to your
engine, including but not limited to failure
of the fuel pump and injectors.

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MULTIMEDIA223
Seek Functions
Seek Up
Push and release the Seek Up button to tune
the radio to the next listenable station or
channel.
During a Seek Up function, if the radio
reaches the starting station after passing
through the entire band two times, the radio
will stop at the station where it began.
Seek Down
Push and release the Seek Down button to
tune the radio to the next listenable station or
channel.
During a Seek Down function, if the radio
reaches the starting station after passing
through the entire band two times, the radio will
stop at the station where it began.
SiriusXM® Satellite Radio Mode — If
Equipped
SiriusXM® Satellite Radio uses direct
satellite-to-receiver broadcasting technology
to provide clear digital sound, coast to coast.
The subscription service provider is SiriusXM®
Satellite Radio. This service offers over 130 channels of music, sports, news,
entertainment, and programming for children,
directly from its satellites and broadcasting
studios. A one-year SiriusXM® Satellite Radio
subscription is included.
Visit siriusxm.com/getallaccess or review your
SiriusXM® Radio pamphlet in your Owner’s
Manual kit for more information.

SiriusXM® and all related marks and logos are
trademarks of SiriusXM® Radio Inc. and its
subsidiaries. SiriusXM® Satellite Radio requires
a subscription, sold separately after the trial
subscription included with vehicle purchase.
Prices and programming are provided by SiriusXM®
and are subject to change. Subscriptions
governed by Terms & Conditions available at

www.siriusxm.com/customeragreement
.
SiriusXM® Radio US service is only available to
those at least 18 years of age in the 48 contiguous
United States, D.C., and PR. Service is available in
Canada; see
www.siriusxm.ca
.
No Subscription
Radios equipped with a Satellite receiver
require a subscription to the SiriusXM® Service.
When the Radio does not have the necessary
subscription, the Radio is able to receive the
Preview channel only.
Acquiring SiriusXM® Subscription
To activate the SiriusXM® Satellite Radio
subscription, US visit siriusxm.com/
getallaccess or call: 1-800-643-2112
Canada visit https://www.siriusxm.ca/ or
call: 1-888-539-7474.
Setting Presets
The Presets are available for all Radio Modes,
and are activated by pushing any of the six
Preset buttons on the faceplate.
When you are receiving a station that you wish
to commit into memory, push and hold the
desired numbered button on the faceplate for
more than two seconds or until you hear a
confirmation beep.
The Radio stores up to 18 presets in each of the
Radio modes.
5

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