2017 RAM CHASSIS CAB ECO mode

gear range will improve performance and extend transmis-
sion life by reducing excessive shifting and heat buildup.
If the transmission temperature exceeds normal operating
limits, the powertrain controller will modify the transmis-
sion shift schedule and expand the range of torque con-
verter clutch engagement. This is done to prevent trans-
mission 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 sig-
nificant additional 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. During cold temperatures, transmission operation may be
modified depending on engine and transmission tempera-
ture as well as vehicle speed. This feature improves warm
up time of the engine and transmission to achieve maxi-
mum efficiency. Engagement of the torque converter clutch
is inhibited until the transmission fluid is warm (refer to
the “Note” under “Torque Converter Clutch” in this sec-
tion).
On models with 66RFE transmission, top overdrive gear is
also inhibited until the transmission fluid is warm, and
during extremely cold temperatures (-16°F [-27°C] or be-
low), operation may briefly be limited to first and direct
gears only. On trucks with AS66RC 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 re-
duced. In all cases, normal operation will resume once the
transmission temperature has risen to a suitable level. 5STARTING AND OPERATING 331

Transmission Limp Home Mode
Transmission function is monitored electronically for ab-
normal 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 fourth gear (for 66RFE transmission) or third gear (for
AS66RC transmission) regardless of which forward gear is
selected. If an AS66RC 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 damag-
ing 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 recom-
mend that you visit your authorized dealer at your earliest
possible convenience. Your authorized dealer has diagnos-
tic equipment to determine if the problem could recur.
If the transmission cannot be reset, authorized dealer
service is required.
Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control allows the
driver to limit the highest available gear when the trans-
mission is in DRIVE. For example, if you set the transmis-
sion gear limit to 4 (fourth gear), the transmission will not
shift above fourth gear, but will shift through the lower
gears normally.
You can switch between DRIVE and ERS mode at any
vehicle speed. When the gear selector is in the DRIVE
position, the transmission will operate automatically, shift-
ing between all available gears. Tapping the ERS (-) switch
will activate ERS mode, display the current gear in the332 STARTING AND OPERATING

• The transmission fluid has reached an adequate tem-
perature.
• The engine coolant has reached an adequate tempera-
ture.
• Vehicle speed is sufficiently high.
• The TOW/HAUL switch has not been activated.
• The driver is not heavily pressing the accelerator.
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 maneu-
vers. 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. TOW/HAUL Switch334 STARTING AND OPERATING

POWER TAKE OFF OPERATION — IF EQUIPPED
(CHASSIS CAB ONLY)
This vehicle when equipped with PTO Prep and the
AS66RC 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” or “mobile” mode. The vehicles will be
factory set to the “stationary” mode. To select “mobile”
mode, you will need to enter the commercial vehicle menu
on the instrument cluster screen and select mobile PTO
mode. Details of the PTO selection modes and further PTO
information is available at the Ram Truck Bodybuilders
web site. www.rambodybuilder.com
AS66RC Six-Speed Automatic Transmission Only
The PTO drive gear (part of the AS66RC) operates at torque
converter turbine speed. The turbine speed will be less
than engine speed when the torque converter clutch is not
engaged and will be same as engine speed when the torque
converter clutch is engaged. Stationary Mode
To operate the PTO in this mode the vehicle must meet the
following conditions:
• Transmission in PARK position (vehicles equipped with
automatic transmission.)
• PTO switch has been activated.
• Parking brake applied (vehicles equipped with manual
transmission).
• Brake pedal must not be applied.
• Vehicle engine must be running.
• No vehicle, brake or clutch switch faults present.
• PTO must be correctly installed using the vehicle pro-
vided circuits.
The instrument cluster will display a  PTO On  message for
five seconds if the above conditions are met. Otherwise, the
instrument cluster will display a message  To Operate PTO
Shift To Park  indicating what operator action should be
taken to engage the PTO mode.336 STARTING AND OPERATING

Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, the TCS may
apply brake pressure to the spinning wheel(s) and/or
reduce engine power to provide enhanced acceleration and
stability. A feature of the TCS, Brake Limited Differential
(BLD), functions similar to a limited slip differential and
controls the wheel spin across a driven axle. If one wheel
on a driven axle is spinning faster than the other, the
system will apply the brake of the spinning wheel. This
will allow more engine torque to be applied to the wheel
that is not spinning. BLD may remain enabled even if TCS
and ESC are in a reduced mode.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESC corrects
for oversteering or understeering of the vehicle by apply-
ing the brake of the appropriate wheel(s) to assist in
counteracting the oversteer or understeer condition. En-
gine power may also be reduced to help the vehicle
maintain the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match the intended path, ESC applies the brake of the appropriate
wheel to assist in counteracting the oversteer or understeer
condition.
• Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
• Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” located
in the instrument cluster will start to flash as soon as the ESC
system becomes active. The “ESC Activation/Malfunction
Indicator Light” also flashes when the TCS is active. If the
“ESC Activation/Malfunction Indicator Light” begins to
flash during acceleration, ease up on the accelerator and
apply as little throttle as possible. Be sure to adapt your
speed and driving to the prevailing road conditions.
WARNING!• Electronic Stability Control (ESC) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ESC cannot prevent accidents, in-
cluding those resulting from excessive speed in (Continued)358 STARTING AND OPERATING

WARNING! (Continued)turns, driving on very slippery surfaces, or hydro-
planing. ESC also cannot prevent accidents resulting
from loss of vehicle control due to inappropriate
driver input for the conditions. Only a safe, attentive,
and skillful driver can prevent accidents. The capa-
bilities of an ESC equipped vehicle must never be
exploited in a reckless or dangerous manner which
could jeopardize the user ’s safety or the safety of
others.
• Vehicle modifications, or failure to properly main-
tain your vehicle, may change the handling charac-
teristics of your vehicle, and may negatively affect
the performance of the ESC system. Changes to the
steering system, suspension, braking system, tire
type and size or wheel size may adversely affect ESC
performance. Improperly inflated and unevenly
worn tires may also degrade ESC performance. Any
vehicle modification or poor vehicle maintenance
that reduces the effectiveness of the ESC system can
increase the risk of loss of vehicle control, vehicle
rollover, personal injury and death. ESC Operating Modes
NOTE: Depending upon model and mode of operation, the
ESC system may have multiple operating modes.
ESC On
This is the normal operating mode for the ESC. Whenever
the vehicle is started, the ESC system will be in this mode.
This mode should be used for most driving conditions.
Alternate ESC modes should only be used for specific
reasons as noted in the following paragraphs.
Partial Off
The “Partial Off” mode is intended for times when a more
spirited driving experience is desired. This mode may
modify TCS and ESC thresholds for activation, which
allows for more wheel spin than normally allowed. This
mode may be useful if the vehicle becomes stuck.
To enter the “Partial Off” mode, momentarily push the
“ESC Off” switch and the “ESC Off Indicator Light” will
illuminate. To turn the ESC on again, momentarily push
the “ESC Off” switch and the “ESC Off Indicator Light”
will turn off. 5STARTING AND OPERATING 359

NOTE: For vehicles with multiple partial ESC modes a
momentary button push will toggle the ESC mode. Mul-
tiple momentary button pushed may be required to return
to ESC On.
NOTE:
• When in “Partial Off” mode, the TCS functionality of
ESC, (except for the limited slip feature described in the
TCS section), has been disabled and the “ESC Off
Indicator Light” will be illuminated. When in “Partial
Off” mode, the engine power reduction feature of TCS is
disabled, and the enhanced vehicle stability offered by
the ESC system is reduced.
• Trailer Sway control (TSC) is disabled when the ESC
system is in the “Partial Off” mode.
Full Off – If Equipped
This mode is intended for off-highway or off-road use only
and should not be used on any public roadways. In this
mode, TCS and ESC features are turned OFF. To enter the
“Full Off” mode, push and hold the “ESC Off” switch for
five seconds while the vehicle is stopped with the engine
running. After five seconds, a chime will sound, the “ESC
Off Indicator Light” will illuminate, and the “ESC OFF” message will display in the instrument cluster. To turn ESC
on again, momentarily push the “ESC Off” switch.
NOTE: System may switch from ESC “Full Off” to “Partial
Off” mode when vehicle exceeds a predetermined speed.
When the vehicle speed slows below the predetermined
speed the system will return to ESC “Full Off”.
ESC modes may also be affected by drive modes (if equipped).
WARNING!• In the ESC “Full Off” mode, the engine torque
reduction and stability features are disabled. There-
fore, enhanced vehicle stability offered by the ESC
system is unavailable. In an emergency evasive ma-
neuver, the ESC system will not engage to assist in
maintaining stability. ESC “Full Off” mode is in-
tended for off-highway or off-road use only.
• With the ESC switched off, the enhanced vehicle
stability offered by ESC is unavailable. In an emer-
gency evasive maneuver, the ESC system will not
engage to assist in maintaining stability. ESC “Full
Off” mode is only intended for off-highway or
off-road use. (Continued)360 STARTING AND OPERATING

WARNING! (Continued)• The Electronic Stability Control (ESC) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions. ESC cannot prevent all
accidents, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. ESC also cannot prevent collisions.
ESC Activation/Malfunction Indicator Light and ESC
OFF Indicator Light
The “ESC Activation/Malfunction Indicator
Light” in the instrument cluster will come on
when the ignition switch is turned to the ON
position. It should go out with the engine run-
ning. If the “ESC Activation/Malfunction Indicator Light”
comes on continuously with the engine running, a mal-
function has been detected in the ESC system. If this light
remains on after several ignition cycles, and the vehicle has
been driven several miles (kilometers) at speeds greater
than 30 mph (48 km/h), see your authorized dealer as soon
as possible to have the problem diagnosed and corrected. The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster) starts to flash as soon as the
tires lose traction and the ESC system becomes active. The
“ESC Activation/Malfunction Indicator Light” also flashes
when TCS is active. If the “ESC Activation/Malfunction
Indicator Light” begins to flash during acceleration, ease
up on the accelerator and apply as little throttle as possible.
Be sure to adapt your speed and driving to the prevailing
road conditions.
NOTE:
• The “ESC Activation/Malfunction Indicator Light” and
the “ESC OFF Indicator Light” come on momentarily
each time the ignition switch is turned ON.
• Each time the ignition is turned ON, the ESC system will
be ON even if it was turned off previously.
• The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver
that caused the ESC activation.
The “ESC OFF Indicator Light” indicates the
customer has elected to have the Electronic Sta-
bility Control (ESC) in a reduced mode. 5STARTING AND OPERATING 361