2021 RAM CHASSIS CAB display

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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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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164STARTING AND OPERATING
If necessary, add fluid to restore to the proper
indicated level. With a clean cloth, wipe any
spilled fluid from all surfaces Ú page 444.
CRUISE CONTROL SYSTEMS — IF EQUIPPED
Your vehicle may be equipped with the Cruise
Control system, or the Adaptive Cruise Control
(ACC) system:
Cruise Control for cruising at a constant
preset speed.
Adaptive Cruise Control (ACC) for maintaining
a set distance between you and the vehicle
ahead using Fixed Speed Cruise Control to
automatically adjust the preset speed.
NOTE:
In vehicles equipped with ACC, if an ACC
distance is not set, Fixed Speed Cruise Control will not detect vehicles directly ahead of you.
Always be aware of the mode selected.
CRUISE CONTROL — IF EQUIPPED
When engaged, the Cruise Control takes over
accelerator operations at speeds greater than
20 mph (32 km/h), or 25 mph (40 km/h),
depending on the powertrain equipped in the
vehicle.
The Cruise Control buttons are located on the
right side of the steering wheel.

Cruise Control Buttons
NOTE:
In order to ensure proper operation, the Cruise
Control system has been designed to shut down
if multiple speed control functions are operated
at the same time. If this occurs, the Cruise
Control system can be reactivated by pushing
the Cruise Control on/off button and resetting
the desired vehicle set speed.
To Activate
Push the on/off button to activate the Cruise
Control. The cruise indicator light in the
instrument cluster display will illuminate.
To turn the system off, push the on/off button
a second time. The cruise indicator light will turn
off. The system should be turned off when not in
use.
CAUTION!
Do not use chemical flushes in your power
steering system as the chemicals can
damage your power steering components.
Such damage is not covered by the New
Vehicle Limited Warranty.
1 — On/Off Button
2 — CANCEL
3 — RES (+)
4 — SET (-)
WARNING!
Leaving the Cruise Control system on
when not in use is dangerous. You could
accidentally set the system or cause it to go
faster than you want. You could lose control
and have an accident. Always leave the
system off when you are not using it.

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STARTING AND OPERATING165
To Set A Desired Speed
Turn the Cruise Control on. When the vehicle
has reached the desired speed, push the SET (-)
button and release. Release the accelerator
and the vehicle will operate at the selected
speed. Once a speed has been set, a message
“CRUISE CONTROL SET TO MPH (km/h)” will
appear indicating the set speed. A cruise
indicator lamp, along with set speed will also
appear and stay on in the instrument cluster
display when the speed is set.
NOTE:
The vehicle should be traveling at a steady
speed and on level ground before pushing the
SET (-) button.
To Vary The Speed Setting
To Increase Or Decrease The Set Speed
When Cruise Control is set, you can increase
the speed by pushing the RES (+) button, or
decrease speed by pushing the SET (-) button.
U.S. Speed (mph)
Pushing the RES (+) button, or SET (-) button
once will result in a 1 mph speed adjustment.
Each subsequent tap of the button results in
an adjustment of 1 mph.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
Metric Speed (km/h)
Pushing the RES (+), or SET (-) button once
will result in a 1 km/h speed adjustment.
Each subsequent tap of the button results in
an adjustment of 1 km/h.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
To Accelerate For Passing
While the Cruise Controls is set, press the
accelerator as you would normally. When the
pedal is released, the vehicle will return to the
set speed.
Using Cruise Control On Hills
The transmission may downshift on hills to
maintain the vehicle set speed.
The Cruise Control system maintains speed up
and down hills. A slight speed change on
moderate hills is normal. On steep hills, a greater speed loss or gain may occur so it may
be preferable to drive without Cruise Control.
To Resume Speed
To resume a previously set speed, push the
RES (+) button and release. Resume can be
used at any speed above 20 mph (32 km/h).
To Deactivate
A soft tap on the brake pedal, pushing the
CANCEL button, or normal brake pressure while
slowing the vehicle will deactivate the Cruise
Control without erasing the set speed from
memory.
WARNING!
Cruise Control can be dangerous where the
system cannot maintain a constant speed.
Your vehicle could go too fast for the
conditions, and you could lose control and
have an accident. Do not use Cruise Control
in heavy traffic or on roads that are winding,
icy, snow-covered or slippery.
4

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168STARTING AND OPERATING
Adaptive Cruise Control (ACC) Menu
The instrument cluster display will show the
current ACC system settings. The information it
displays depends on ACC system status.
Push the ACC on/off button until one of the
following appears in the instrument cluster
display:
Adaptive Cruise Control Off
When ACC is deactivated, the display will read
“Adaptive Cruise Control Off.”
Adaptive Cruise Control Ready
When ACC is activated, but the vehicle speed
setting has not been selected, the display will
read “Adaptive Cruise Control Ready.”
Adaptive Cruise Control Set
When the RES (+) or the SET(-) button is pushed,
the display will read “ACC SET.”
When ACC is set, the set speed will show in the
instrument cluster display.
The ACC screen may display once again if any of
the following ACC activity occurs:
System Cancel
Driver Override
System Off
ACC Proximity Warning
ACC Unavailable Warning
The instrument cluster display will return to the
last display selected after five seconds of no
ACC display activity.
Activating Adaptive Cruise Control (ACC)
The minimum set speed for the ACC system is
20 mph (32 km/h).
When the system is turned on and in the ready
state, the instrument cluster display will read
“ACC Ready.”
When the system is off, the instrument cluster
display will read “Adaptive Cruise Control (ACC)
Off.”
NOTE:
You cannot engage ACC under the following
conditions:
When in 4WD Low
When brakes are applied
When the parking brake is applied
When the automatic transmission is in PARK,
REVERSE or NEUTRAL
When the vehicle speed is below the
minimum speed range
When the brakes are overheated
When the driver’s door is open at low speeds
When the driver’s seat belt is unbuckled at
low speed
Electronic Stability Control (ESC) Full Off
mode is active
To Activate/Deactivate
Push and release the Adaptive Cruise Control
(ACC) on/off button. The ACC menu in the
instrument cluster displays “ACC Ready.”
To turn the system off, push and release the
Adaptive Cruise Control (ACC) on/off button
again. At this time, the system will turn off
and the instrument cluster display will show
“Adaptive Cruise Control (ACC) Off.”

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STARTING AND OPERATING169
To Set A Desired ACC Speed
When the vehicle reaches the speed
desired, push the SET (-) button and release.
The instrument cluster display will show the set
speed.
NOTE:
Fixed Speed Cruise Control can be used without
an ACC distance set. To change between the
different modes, push the ACC on/off button
which turns the ACC and the Fixed Speed Cruise
Control off. Pushing the Fixed Speed Cruise
Control on/off button will result in turning on
(changing to) Fixed Speed Cruise Control mode. If ACC is set when the vehicle speed is
below
20 mph (32 km/h), the set speed will default to
20 mph (20 km/h).
NOTE:
Fixed Speed Cruise Control cannot be set below
20 mph (32 km/h).
If either system is set when the vehicle speed is
above 20 mph (32 km/h), the set speed shall
be the current speed of the vehicle. NOTE:
Keeping your foot on the accelerator pedal
can cause the vehicle to continue to accel
-
erate beyond the set speed. If this occurs, the
message “ACC DRIVER OVERRIDE” will
display in the instrument cluster display.
If you continue to accelerate beyond the set
speed while an ACC distance is also set, the
system will not be controlling the distance
between your vehicle and the vehicle ahead.
The vehicle speed will only be determined by
the position of the accelerator pedal.
To Cancel
The following conditions cancel the ACC or Fixed
Speed Cruise Control systems:
The brake pedal is applied.
The CANCEL button is pushed.
An Anti-Lock Brake System (ABS) event
occurs.
WARNING!
Leaving the Adaptive Cruise Control (ACC)
system on when not in use is dangerous.
You could accidentally set the system or
cause it to go faster than you want. You could
lose control and have a collision. Always leave
the system off when you are not using it.
WARNING!
In the Fixed Speed Cruise Control mode
(no ACC distance set), the system will not
react to vehicles ahead. In addition, the
proximity warning does not activate and no
alarm will sound even if you are too close to
the vehicle ahead since neither the presence
of the vehicle ahead nor the vehicle-to-vehicle
distance is detected. Be sure to maintain a
safe distance between your vehicle and the
vehicle ahead. Always be aware which mode
is selected.
4

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170STARTING AND OPERATING
The gear selector is removed from the DRIVE
position.
The Electronic Stability Control/Traction
Control System (ESC/TCS) activates.
The vehicle parking brake is applied.
Driver seat belt is unbuckled at low speeds.
Driver door is opened at low speeds.
A Trailer Sway Control (TSC) event occurs.
The driver switches ESC to Full Off mode.
The braking temperature exceeds normal
range (overheated).
The trailer brake is applied manually
(if equipped).
The following conditions will only cancel the ACC
system:
Driver seat belt is unbuckled at low speeds
Driver door is opened at low speeds
To Turn Off
The system will turn off and clear the set speed
in memory if:
The Adaptive Cruise Control (ACC) on/off
button is pushed
The Fixed Speed Cruise Control on/off button
is pushed
The ignition is placed in the OFF position
4WD Low is engaged
To Resume
If there is a set speed in memory push the RES
(+) button and then remove your foot from the
accelerator pedal. The instrument cluster
display will display the last set speed.
Resume can be used at any speed above
20 mph (32 km/h) when only Fixed Speed
Cruise Control is being used.
Resume can be used at any speed above 0 mph
(0 km/h) when ACC is active. NOTE: 
While in ACC mode when the vehicle comes
to a complete stop longer than two seconds,
the system will cancel. The driver will have
to apply the brakes to keep the vehicle at a
standstill.
 ACC cannot be resumed if there is a
stationary vehicle in front of your vehicle in
close proximity.
WARNING!
The Resume function should only be used if
traffic and road conditions permit. Resuming
a set speed that is too high or too low for
prevailing traffic and road conditions could
cause the vehicle to accelerate or decelerate
too sharply for safe operation. Failure to
follow these warnings can result in a collision
and death or serious personal injury.

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