stop start RAM CHASSIS CAB 2020 Service Manual

STARTING AND OPERATING221
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 circum -
ference 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
current position indicator light will turn off,
the selected position indicator light will flash
until the transfer case completes the shift.
When the shift is complete, the position indi -
cator light for the selected position will stop
flashing and remain on. 2WD To 4WD HIGH
Push the desired position on the 4WD control
switch to shift the transfercase. Shifts between
2WD and 4WD HIGH can be done with the
vehicle stopped or in motion. With the vehicle in
motion, the transfer case will engage/disen
-
gage faster if you momentarily release the
accelerator pedal after turning the control
switch. If the vehicle is stopped, the ignition
switch must be in the ON position with the
engine either running or off. This shift cannot be
completed if the ignition switch is in the ACC
position.
NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD HIGH if the front and/or
rear wheels are spinning (no traction). In this
situation, the selected position indicator light
will flash and the original position indicator light
will remain on. At this time, reduce speed and
stop spinning the wheels to complete the shift.
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 or death.
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222STARTING AND OPERATING
2WD Or 4WD HIGH To 4WD LOW
NOTE:
When shifting into or out of 4WD LOW some
gear noise may be heard. This noise is normal
and is not detrimental to the vehicle or occu -
pants.
Shifting can be performed with the vehicle
rolling 2 to 3 mph (3 to 5 km/h) or completely
stopped. You can use either of the following
procedures:
Preferred Procedure

1. With the engine running, slow the vehicle to 2 to 3 mph (3 to 5 km/h).

2. Shift the transmission into NEUTRAL.
3. While still rolling, 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. 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 transmis -
sion 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.
Electronically Shifted Transfer Case (Six
Speed Transmisson) — If Equipped
The electronic shift transfer case is operated by
the 4WD Control Switch (Transfer Case Switch),
which is located on the instrument panel.

Four-Position/On-Demand 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)

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224STARTING AND OPERATING
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 illumi
-
nates during driving, it means that the
four-wheel drive system is not functioning prop -
erly 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). Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and circum
-
ference 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. To retry a shift: return the
control switch back to the original position,
make certain all shift requirements have
been met, wait five seconds and try the shift
again.
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 OPERATING225
If all the requirements to select a new
transfer case position have been met, the
current position indicator light will turn OFF,
the selected position indicator light will flash
until the transfer case completes the shift.
When the shift is complete, the position indi -
cator light for the selected position will stop
flashing and remain ON.
2WD To 4WD HIGH
Push the desired position on the 4WD control
switch to shift the transfercase. Shifts between
2WD and 4WD HIGH can be done with the
vehicle stopped or in motion. With the vehicle in
motion, the transfer case will engage/disen -
gage faster if you momentarily release the
accelerator pedal after turning the control
switch. If the vehicle is stopped, the ignition
switch must be in the ON position with the
engine either running or off. This shift cannot be
completed if the ignition switch is in the ACC
position.
NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD HIGH if the front and/or
rear wheels are spinning (no traction). In this
situation, the selected position indicator light will flash and the original position indicator light
will remain on. At this time, reduce speed and
stop spinning the wheels to complete the shift.
2WD Or 4WD HIGH To 4WD LOW
NOTE:
When shifting into or out of 4WD LOW some
gear noise may be heard. This noise is normal
and is not detrimental to the vehicle or occu
-
pants.
Shifting can be performed with the vehicle
rolling 2 to 3 mph (3 to 5 km/h) or completely
stopped. You can use either of the following
procedures:
Preferred Procedure

1. With the engine running, slow the vehicle to 2 to 3 mph (3 to 5 km/h).

2. Shift the transmission into NEUTRAL.
3. While still rolling, 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. 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 transmis -
sion 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.
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STARTING AND OPERATING227
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)
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).
Shifting Procedure — Manually Shifted
Transfer Case
2H To 4H
Shifting between 2H and 4H can be made with
the vehicle stopped or in motion. If the vehicle
is in motion, shifts can be made up to 55 mph
(88 km/h). With the vehicle in motion, the
transfer case will engage/disengage faster if
you momentarily release the accelerator pedal
after completing the shift. Apply a constant
force when shifting the transfer case lever.
2H Or 4H To 4L
NOTE:
When shifting into or out of 4L some gear noise
may be heard. This noise is normal and is not
detrimental to the vehicle or occupants.
With the vehicle rolling at 2 to 3 mph
(3 to 5 km/h), shift the transmission into
NEUTRAL. While the vehicle is coasting at
2 to 3 mph (3 to 5 km/h), shift the transfer case
lever firmly to the desired position. Do not
pause in transfer case Neutral.
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.
CAUTION!
Do not use 4L (Low) range when operating
the vehicle on dry pavement. Driveline
hardware damage can result.
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228STARTING AND OPERATING
NOTE:
Pausing in transfer case Neutral in vehicles
equipped with an automatic transmission
may require shutting the engine OFF to avoid
gear clash while completing the shift. If diffi -
culty occurs, shift the transmission into
Neutral, hold your foot on the brake, and turn
the engine OFF. Complete the range shift to
the desired mode.
Shifting into or out of 4L is possible with the
vehicle completely stopped, however diffi -
culty may occur due to the mating clutch
teeth not being properly aligned. Several
attempts may be required for clutch teeth
alignment and shift completion to occur. The
preferred method is with the vehicle rolling 2
to 3 mph (3 to 5 km/h). Avoid attempting to engage or disengage 4L with the vehicle
moving faster than 2 to 3 mph (3 to 5 km/h).
Do not attempt to shift into or out of 4L while
the transmission is in gear.
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in
the instrument cluster is used to alert the driver
that the front axle is fully engaged and all four
wheels are driving.
LIMITED-SLIP DIFFERENTIAL
The limited-slip differential provides additional
traction on snow, ice, mud, sand and gravel,
particularly when there is a difference between
the traction characteristics of the surface under
the right and left rear wheels. During normal
driving and cornering, the limited-slip unit
performs similarly to a conventional differential.
On slippery surfaces, however, the differential
delivers more of the driving effort to the rear
wheel having the better traction.
The limited-slip differential is especially helpful
during slippery driving conditions. With both
rear wheels on a slippery surface, a slight appli -
cation of the accelerator will supply maximum
traction. When starting with only one rear wheel
on an excessively slippery surface, slight
momentary application of the parking brake
may be necessary to gain maximum traction. Care should be taken to avoid sudden accelera-
tions when both rear wheels are on a slippery
surface. This could cause both rear wheels to
spin, and allow the vehicle to slide sideways on
the crowned surface of a road or in a turn.
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 transmis
-
sion 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-commerical/
body-builders-guide.html
WARNING!
On vehicles equipped with a limited-slip
differential never run the engine with one rear
wheel off the ground since the vehicle may
drive through the rear wheel remaining on the
ground. You could lose control of the vehicle.

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232STARTING AND OPERATING
(Continued)
ADAPTIVE CRUISE CONTROL (ACC) — IF
EQUIPPED
Adaptive Cruise Control (ACC) increases the
driving convenience provided by cruise control
while traveling on highways and major road-
ways. However, it is not a safety system and not
designed to prevent collisions. Speed Control
function performs differently. Please refer to
the proper section within this chapter.
ACC will allow you to keep cruise control
engaged in light to moderate traffic conditions
without the constant need to reset your cruise
control. ACC utilizes a radar sensor and a
forward facing camera designed to detect a
vehicle directly ahead of you.
NOTE:
If the sensor does not detect a vehicle ahead
of you, ACC will maintain a fixed set speed.
If the ACC sensor detects a vehicle ahead,
ACC will apply limited braking or accelerate
(not to exceed the original set speed) auto -
matically to maintain a preset following
distance, while matching the speed of the
vehicle ahead. The Cruise Control system has two control
modes:
Adaptive Cruise Control mode for main
-
taining an appropriate distance between
vehicles.
Normal (Fixed Speed) Cruise Control mode
for cruising at a constant preset speed. For
additional information, refer to “Normal
(Fixed Speed) Cruise Control Mode” in this
section.
NOTE:
Normal (Fixed Speed) Cruise Control will not
react to preceding vehicles. Always be aware of
the mode selected.
You can change the mode by using the Cruise
Control buttons. The two control modes func -
tion differently. Always confirm which mode is
selected.
WARNING!
Adaptive Cruise Control (ACC) is a conve -
nience system. It is not a substitute for
active driving involvement. It is always the
driver’s responsibility to be attentive of
road, traffic, and weather conditions,
vehicle speed, distance to the vehicle
ahead; and, most importantly, brake opera -
tion to ensure safe operation of the vehicle
under all road conditions. Your complete
attention is always required while driving to
maintain safe control of your vehicle.
Failure to follow these warnings can result
in a collision and death or serious personal
injury.
The ACC system:
Does not react to pedestrians,
oncoming vehicles, and stationary
objects (e.g., a stopped vehicle in a
traffic jam or a disabled vehicle).
Cannot take street, traffic, and weather conditions into account, and may be
limited upon adverse sight distance
conditions.

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STARTING AND OPERATING233
(Continued)
Adaptive Cruise Control (ACC) Operation
The speed control buttons (located on the right
side of the steering wheel) operate the ACC
system.
Adaptive Cruise Control Buttons

NOTE:
Any chassis/suspension or tire size modifica -
tions to the vehicle will affect the performance
of the Adaptive Cruise Control and Forward
Collision Warning System.
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 — Distance Button
3 — RES (+)
4 — SET (-)
5 — CANCEL
6 — Normal (Fixed Speed) Cruise Control On/Off
Button
5

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STARTING AND OPERATING237
Metric Speed (km/h)
Pushing the SET (-) button once will result in
a 1 km/h decrease in set speed. Each subse -
quent tap of the button results in a decrease
of 1 km/h.
If the button is continually pushed, the set
speed will continue to decrease in 10 km/h
decrements until the button is released. The
decrease in set speed is reflected in the
instrument cluster display.
NOTE:
When you override and push the RES (+)
button or SET (-) button, the new set speed
will be the current speed of the vehicle.
When you use the SET (-) button to decel -
erate, if the engine’s braking power does not
slow the vehicle sufficiently to reach the set
speed, the brake system will automatically
slow the vehicle.
The ACC system decelerates the vehicle to a
full stop when following a target vehicle. If an
ACC host vehicle follows a target vehicle to a
standstill, after two seconds the driver will either have to push the RES (+) button, or
apply the accelerator pedal to reengage the
ACC to the existing set speed.
The ACC system maintains set speed when
driving uphill and downhill. However, a slight
speed change on moderate hills is normal. In
addition, downshifting may occur while
climbing uphill or descending downhill. This
is normal operation and necessary to main
-
tain set speed. When driving uphill and down -
hill, the ACC system will cancel if the braking
temperature exceeds normal range (over -
heated).
Setting The Following Distance In ACC
The specified following distance for ACC can be
set by varying the distance setting between four
bars (longest), three bars (long), two bars
(medium) and one bar (short). Using this
distance setting and the vehicle speed, ACC
calculates and sets the distance to the vehicle
ahead. This distance setting displays in the
instrument cluster display.
Distance Setting 4 Bars (Longest)
Distance Setting 3 Bars (Long)

5

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STARTING AND OPERATING239
Trailer Detect — If Equipped
When a trailer is detected, the ACC system auto -
matically defaults to the longest setting (four
bars). The setting can be overridden by pushing
the Distance Button on the steering wheel.
Overtake Aid
When driving with ACC engaged and following a
vehicle, the system will provide an additional
acceleration up to the ACC set speed to assist in
passing the vehicle. This additional acceleration
is triggered when the driver utilizes the left turn
signal and will only be active when passing on
the left hand side.
ACC Operation At Stop
In the event that the ACC system brings your
vehicle to a standstill while following a target
vehicle, if the target vehicle starts moving within
two seconds of your vehicle coming to a stand -
still, your vehicle will resume motion without the
need for any driver action. If the target vehicle does not start moving within
two seconds of your vehicle coming to a stand
-
still, then ACC will cancel and the driver must
take over braking. When the target vehicle
drives off, ACC can be resumed by releasing the
brake and pushing the RES (+) button.
NOTE:
After the ACC system holds your vehicle at a
standstill for approximately two seconds, a
chime will sound and an “ACC may cancel soon”
warning will display. The brakes will release
when ACC is cancelled and the driver must take
over braking.

While ACC is holding your vehicle at a
standstill, if the driver seatbelt is unbuckled or
the driver door is opened, the ACC system will
cancel and the brakes will release. Driver
intervention will be required at this moment.

Adaptive Cruise Control (ACC) Menu
The instrument cluster display will show the
current ACC system settings. The instrument
cluster display is located in the center of the
instrument cluster. The information it displays
depends on ACC system status.
Push the Adaptive Cruise Control (ACC) on/off
button (located on the steering wheel) 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.”
WARNING!
When the ACC system is resumed, the driver
must ensure that there are no pedestrians,
vehicles or objects in the path of the vehicle.
Failure to follow these warnings can result in
a collision and death or serious personal
injury.
5

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