2020 Ram 4500 Chassis Cab clutch

122SAFETY
Hill Start Assist (HSA)
The Hill Start Assist (HSA) system is designed to
mitigate roll back from a complete stop while on
an incline. If the driver releases the brake while
stopped on an incline, HSA will continue to hold
the brake pressure for a short period. If the
driver does not apply the throttle before this
time expires, the system will release brake pres -
sure and the vehicle will roll down the hill as
normal. The following conditions must be met in order
for HSA to activate:
The feature must be enabled.
The vehicle must be stopped.
The park brake must be off.
The driver door must be closed.
The vehicle must be on a sufficient grade.
The gear selection must match vehicle uphill
direction (i.e., vehicle facing uphill is in
forward gear; vehicle backing uphill is in
REVERSE gear).
HSA will work in REVERSE gear and all
forward gears. The system will not activate if
the transmission is in PARK or NEUTRAL. For
vehicles equipped with a manual transmis
-
sion, if the clutch is pressed, HSA will remain
active.
WARNING!
The Brake Assist System (BAS) cannot
prevent the natural laws of physics from
acting on the vehicle, nor can it increase the
traction afforded by prevailing road
conditions. BAS cannot prevent collisions,
including those resulting from excessive
speed in turns, driving on very slippery
surfaces, or hydroplaning. The capabilities of
a BAS-equipped vehicle must never be
exploited in a reckless or dangerous manner,
which could jeopardize the user's safety or
the safety of others.
WARNING!
There may be situations where the Hill Start
Assist (HSA) will not activate and slight rolling
may occur, such as on minor hills or with a
loaded vehicle, or while pulling a trailer. HSA
is not a substitute for active driving
involvement. It is always the driver’s
responsibility to be attentive to distance to
other vehicles, people, and objects, and most
importantly brake operation 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 or serious
personal injury.

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SAFETY181
(Continued)
(Continued)
Air Bag Warning Light
The Air Bag warning light will turn on for four
to eight seconds as a bulb check when the igni
-
tion switch is first placed in ON/RUN. If the light
is either not on during starting, stays on, or
turns on while driving, have the system
inspected at an authorized dealer as soon as
possible. After the bulb check, this light will illu -
minate with a single chime when a fault with the
Air Bag System has been detected. It will stay on
until the fault is removed. If the light comes on
intermittently or remains on while driving, have
an authorized dealer service the vehicle imme -
diately.
Refer to “Occupant Restraint Systems” in
“Safety” for further information.
Defroster
Check operation by selecting the defrost mode
and place the blower control on high speed. You
should be able to feel the air directed against
the windshield. See an authorized dealer for
service if your defroster is inoperable.
Floor Mat Safety Information
Always use floor mats designed to fit your
vehicle. Only use a floor mat that does not inter -
fere with the operation of the accelerator, brake
or clutch pedals. Only use a floor mat that is
securely attached using the floor mat fasteners
so it cannot slip out of position and interfere
with the accelerator, brake or clutch pedals or
impair safe operation of your vehicle in other
ways.
WARNING!
An improperly attached, damaged, folded, or
stacked floor mat, or damaged floor mat
fasteners may cause your floor mat to
interfere with the accelerator, brake, or clutch
pedals and cause a loss of vehicle control. To
prevent SERIOUS INJURY or DEATH:
ALWAYS securely attach your floor mat
using the floor mat fasteners. DO NOT
install your floor mat upside down or turn
your floor mat over. Lightly pull to confirm
mat is secured using the floor mat
fasteners on a regular basis.
ALWAYS REMOVE THE EXISTING FLOOR
MAT FROM THE VEHICLE before
installing any other floor mat. NEVER install
or stack an additional floor mat on top of an
existing floor mat.
ONLY install floor mats designed to fit your
vehicle. NEVER install a floor mat that
cannot be properly attached and secured to
your vehicle. If a floor mat needs to be
replaced, only use a FCA approved floor
mat for the specific make, model, and year
of your vehicle.
ONLY use the driver’s side floor mat on the
driver’s side floor area. To check for inter -
ference, with the vehicle properly parked
with the engine off, fully depress the accel -
erator, the brake, and the clutch pedal (if
present) to check for interference. If your
floor mat interferes with the operation of
any pedal, or is not secure to the floor,
remove the floor mat from the vehicle and
place the floor mat in your trunk.
ONLY use the passenger’s side floor mat on
the passenger’s side floor area.
WARNING! (Continued)
4

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182SAFETY
Periodic Safety Checks You Should Make
Outside The Vehicle
Tires
Examine tires for excessive tread wear and
uneven wear patterns. Check for stones, nails,
glass, or other objects lodged in the tread or
sidewall. Inspect the tread for cuts and cracks.
Inspect sidewalls for cuts, cracks, and bulges.
Check the wheel bolts for tightness. Check the
tires (including spare) for proper cold inflation
pressure.
Lights
Have someone observe the operation of brake
lights and exterior lights while you work the
controls. Check turn signal and high beam indi -
cator lights on the instrument panel.
Door Latches
Check for proper closing, latching, and locking.
Fluid Leaks
Check area under the vehicle after overnight
parking for fuel, coolant, oil, or other fluid leaks.
Also, if gasoline fumes are detected or if fuel, or
brake fluid leaks are suspected, the cause
should be located and corrected immediately.
ALWAYS make sure objects cannot fall or
slide into the driver’s side floor area when
the vehicle is moving. Objects can become
trapped under accelerator, brake, or clutch
pedals and could cause a loss of vehicle
control.
NEVER place any objects under the floor
mat (e.g., towels, keys, etc.). These objects
could change the position of the floor mat
and may cause interference with the accel -
erator, brake, or clutch pedals.
If the vehicle carpet has been removed and
re-installed, always properly attach carpet
to the floor and check the floor mat
fasteners are secure to the vehicle carpet.
Fully depress each pedal to check for inter -
ference with the accelerator, brake, or
clutch pedals then re-install the floor mats.
It is recommended to only use mild soap
and water to clean your floor mats. After
cleaning, always check your floor mat has
been properly installed and is secured to
your vehicle using the floor mat fasteners
by lightly pulling mat.
WARNING! (Continued)

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210STARTING AND OPERATING
If the transmission temperature exceeds
normal operating limits, the powertrain
controller will modify the transmission shift
schedule and expand the range of torque
converter clutch engagement. This is done to
prevent transmission damage due to over -
heating.
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 significant addi -
tional 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 opera
-
tion may be modified depending on engine and
transmission temperature as well as vehicle
speed. This feature improves warm up time of
the engine and transmission to achieve
maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmis -
sion fluid is warm (refer to the “Note” under
“Torque Converter Clutch” in this section).
On trucks with AS66RC or AS69RC transmis -
sion, 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 electroni -
cally for abnormal conditions. If a condition is
detected that could result in transmission
damage, Transmission Limp Home Mode is acti -
vated. In this mode, the transmission remains
in third gear (for AS66RC/AS69RC transmis -
sion) 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 trans
-
mission 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 trans -
mission will return to normal operation.

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212STARTING AND OPERATING
Overdrive Operation
The automatic transmission includes an elec -
tronically 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 transmis -
sion 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 auto
-
matically 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.
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 trans -
mission 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 down -
shift (for engine braking) when the throttle is
closed and/or during steady braking maneu -
vers.

TOW/HAUL Switch

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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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310IN CASE OF EMERGENCY
F56 –15 Amp Blue Additional Diesel Content - If Equipped (DS 1500 Only)
F56 –10 Amp Red Fuel Vapor Blocker Valve - If Equipped (HD Only)
F57 –20 Amp Yellow TCM/PCM / Solenoid Trans Pressure SW (RFE Trans Only)
– If Equipped (HD Only)
Transmission (DS 1500 Only)
F58 –10 Amp Red Bed Lighting (LED) – If Equipped (HD Only)
F60 –15 Amp Blue Underhood Lamp / TCM – If Equipped (DS 1500 Only)
F61 –10 Amp RedUREA Sensor / PM Sensor – If Equipped (DS 1500 LD
Diesel & Cummins Diesel)
F62 –10 Amp Red Air Conditioning Clutch
F63 –20 Amp Yellow Ignition Coils (Gas), Ignition Coils Capacitors (Gas) / Short
Runner Valve Actuator / Urea Heater Control Unit (DS
1500 LD Diesel) / RLY Coil Feed-SCR (DS 1500 LD Diesel)
F64 –25 Amp ClearFuel Injectors / Powertrain Control Module / SRV – If
Equipped
F65 –10 Amp RedMOD Inverter (Wake Up) / Power Port / USB IP / WCPM –
If Equipped (HD Only)
Spare (DS 1500 Only)
F66 –10 Amp RedSunroof / Light and Rain Sensor Module / Inside Rearview
Mirror / Passenger Window SW / USB Port Rear / Feed for
R/A RLY #2 Coil – If Equipped
F67 –10 Amp RedCD / DVD / UCI Port – If Equipped (HD Only)
Bluetooth Hands-Free Module / CD – If Equipped (DS
1500 Only)
Cavity
Cartridge Fuse Micro Fuse Description

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IN CASE OF EMERGENCY311
F68 –10 Amp Red AEB RACAM HTR – If Equipped (HD Only)
F69 –15 Amp Blue SCR Module – If Equipped (HD Only)
F70 –30 Amp GreenFuel Pump Motor / K09 RLY Coil Feed (Cummins Diesel) –
If Equipped
F71 –25 Amp ClearAmplifier / Active Noise Cancelation – If Equipped (HD
Only)
F72 –10 Amp RedPCM / DC/DC Converter Voltage– If Equipped (DS 1500
Only)
F73 –20 Amp Yellow Fuel Transfer Pump (Rear Tank) – If Equipped (HD Only)
F74 –20 Amp Yellow Brake Vacuum Pump Gas/Diesel – If Equipped (DS 1500
Only)
F74 –10 Amp Red Backup Alarm – If Equipped (HD Only)
F75 –10 Amp RedATMM / Coil-SCR Module RLY– If Equipped (HD Only)
Coolant Temperature Valve – If Equipped (DS 1500 Only)
F76 –10 Amp RedElectronic Stability Control (HD Only)
Brake System Module / Stop Lamp Switch / Electric Park
Brake / Clutch Pedal Switch (DS 1500 Only)
F77 –10 Amp Red
Drivetrain Control Module / Front Axle Disconnect Module /
TCM/ STOM (HD Only)

Drivetrain Control Module / ELSD / Front Axle Disconnect
Module / Transmission Control Relay / RDM / Power Take
Off Unit – If Equipped (DS 1500 Only)
Cavity
Cartridge Fuse Micro Fuse Description
6

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