service RAM CHASSIS CAB 2020 Service Manual

SAFETY151
Supplemental Restraint Systems (SRS)
Some of the safety features described in this
section may be standard equipment on some
models, or may be optional equipment on
others. If you are not sure, ask an authorized
dealer.
The air bag system must be ready to protect you
in a collision. The Occupant Restraint Controller
(ORC) monitors the internal circuits and inter -
connecting wiring associated with the electrical
Air Bag System Components. Your vehicle may
be equipped with the following Air Bag System
Components:
Air Bag System Components
Occupant Restraint Controller (ORC)
Air Bag Warning Light
Steering Wheel and Column
Instrument Panel
Knee Impact Bolsters
Driver and Front Passenger Air Bags
Seat Belt Buckle Switch
Supplemental Side Air Bags — If Equipped
Front and Side Impact Sensors — If Equipped
Seat Belt Pretensioners — If Equipped
Air Bag Warning Light
The ORC monitors the readiness of
the electronic parts of the air bag
system whenever the ignition switch
is in the START or ON/RUN position. If
the ignition switch is in the OFF position or in the
ACC position, the air bag system is not on and
the air bags will not inflate.
The ORC contains a backup power supply
system that may deploy the air bag system even
if the battery loses power or it becomes discon -
nected prior to deployment.
The ORC turns on the Air Bag Warning Light in
the instrument panel for approximately four to
eight seconds for a self-check when the ignition
switch is first in the ON/RUN position. After the
self-check, the Air Bag Warning Light will turn
off. If the ORC detects a malfunction in any part
of the system, it turns on the Air Bag Warning
Light, either momentarily or continuously. A
single chime will sound to alert you if the light
comes on again after initial startup. The ORC also includes diagnostics that will illu-
minate the instrument panel Air Bag Warning
Light if a malfunction is detected that could
affect the air bag system. The diagnostics also
record the nature of the malfunction. While the
air bag system is designed to be maintenance
free, if any of the following occurs, have an
authorized dealer service the air bag system
immediately.
The Air Bag Warning Light does not come on
during the four to eight seconds when the
ignition switch is first in the ON/RUN position.
The Air Bag Warning Light remains on after
the four to eight-second interval.
The Air Bag Warning Light comes on intermit
-
tently or remains on while driving.
NOTE:
If the speedometer, tachometer, or any engine
related gauges are not working, the Occupant
Restraint Controller (ORC) may also be
disabled. In this condition the air bags may not
be ready to inflate for your protection. Have an
authorized dealer service the air bag system
immediately.
4

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152SAFETY
(Continued)
Front Air Bags
This vehicle has front air bags and lap/shoulder
belts for both the driver and front passenger.
The front air bags are a supplement to the seat
belt restraint systems. The driver front air bag is
mounted in the center of the steering wheel.
The passenger front air bag is mounted in the
instrument panel, above the glove compart-
ment. The words “SRS AIRBAG” or “AIRBAG” are
embossed on the air bag covers.
Front Air Bag/Knee Bolster Locations

Driver And Passenger Front Air Bag Features
The Advanced Front Air Bag system has multi
-
stage driver and front passenger air bags. This
system provides output appropriate to the
severity and type of collision as determined by
the Occupant Restraint Controller (ORC), which
may receive information from the front impact
sensors (if equipped) or other system compo -
nents.
The first stage inflator is triggered immediately
during an impact that requires air bag deploy -
ment. A low energy output is used in less severe
collisions. A higher energy output is used for
more severe collisions.
WARNING!
Ignoring the Air Bag Warning Light in your
instrument panel could mean you won’t have
the air bag system to protect you in a
collision. If the light does not come on as a
bulb check when the ignition is first turned
on, stays on after you start the vehicle, or if it
comes on as you drive, have an authorized
dealer service the air bag system
immediately.
1 — Driver And Passenger Front Air Bags
2 — Driver And Passenger Knee Impact Bolsters
WARNING!
Being too close to the steering wheel or
instrument panel during front air bag
deployment could cause serious injury,
including death. Air bags need room to
inflate. Sit back, comfortably extending
your arms to reach the steering wheel or
instrument panel.
Never place a rear-facing child restraint in
front of an air bag. A deploying passenger
front air bag can cause death or serious
injury to a child 12 years or younger,
including a child in a rear-facing child
restraint.
Never install a rear-facing child restraint in
the front seat of a vehicle. Only use a
rear-facing child restraint in the rear seat. If
the vehicle does not have a rear seat, do
not transport a rear-facing child restraint in
that vehicle.
WARNING! (Continued)

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SAFETY157
Air Bag System Components
NOTE:
The Occupant Restraint Controller (ORC) moni -
tors the internal circuits and interconnecting
wiring associated with electrical Air Bag System
Components listed below:
Occupant Restraint Controller (ORC)
Air Bag Warning Light
Steering Wheel and Column
Instrument Panel
Knee Impact Bolsters
Driver and Front Passenger Air Bags
Seat Belt Buckle Switch
Supplemental Side Air Bags — If Equipped
Front and Side Impact Sensors — If Equipped
Seat Belt Pretensioners — If Equipped
If A Deployment Occurs
The front air bags are designed to deflate imme -
diately after deployment. NOTE:
Front and/or side air bags will not deploy in all
collisions. This does not mean something is
wrong with the air bag system.
If you do have a collision which deploys the air
bags, any or all of the following may occur:
The air bag material may sometimes cause
abrasions and/or skin reddening to the occu
-
pants as the air bags deploy and unfold. The
abrasions are similar to friction rope burns or
those you might get sliding along a carpet or
gymnasium floor. They are not caused by
contact with chemicals. They are not perma -
nent and normally heal quickly. However, if
you haven’t healed significantly within a few
days, or if you have any blistering, see your
doctor immediately.
As the air bags deflate, you may see some
smoke-like particles. The particles are a
normal by-product of the process that gener -
ates the non-toxic gas used for air bag infla -
tion. These airborne particles may irritate the
skin, eyes, nose, or throat. If you have skin or
eye irritation, rinse the area with cool water. For nose or throat irritation, move to fresh air.
If the irritation continues, see your doctor. If
these particles settle on your clothing, follow
the garment manufacturer’s instructions for
cleaning.
Do not drive your vehicle after the air bags have
deployed. If you are involved in another colli -
sion, the air bags will not be in place to protect
you.
NOTE:
Air bag covers may not be obvious in the inte -
rior trim, but they will open during air bag
deployment.
After any collision, the vehicle should be
taken to an authorized dealer immediately.
WARNING!
Deployed air bags and seat belt
pretensioners cannot protect you in another
collision. Have the air bags, seat belt
pretensioners, and the seat belt retractor
assemblies replaced by an authorized dealer
immediately. Also, have the Occupant
Restraint Controller System serviced as well.
4

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SAFETY159
Event Data Recorder (EDR)
This vehicle is equipped with an Event Data
Recorder (EDR). The main purpose of an EDR is
to record, in certain crash or near crash-like
situations, such as an air bag deployment or
hitting a road obstacle, data that will assist in
understanding how a vehicle’s systems
performed. The EDR is designed to record data
related to vehicle dynamics and safety systems
for a short period of time, typically 30 seconds
or less. The EDR in this vehicle is designed to
record such data as:
How various systems in your vehicle were
operating;
Whether or not the driver and passenger
safety belts were buckled/fastened;
How far (if at all) the driver was depressing
the accelerator and/or brake pedal; and,
How fast the vehicle was traveling.
These data can help provide a better under -
standing of the circumstances in which crashes
and injuries occur. NOTE:
EDR data are recorded by your vehicle only if a
non-trivial crash situation occurs; no data are
recorded by the EDR under normal driving
conditions and no personal data (e.g., name,
gender, age, and crash location) are recorded.
However, other parties, such as law enforce
-
ment, could combine the EDR data with the type
of personally identifying data routinely acquired
during a crash investigation.
To read data recorded by an EDR, special equip -
ment is required, and access to the vehicle or
the EDR is needed. In addition to the vehicle
manufacturer, other parties, such as law
enforcement, that have the special equipment,
can read the information if they have access to
the vehicle or the EDR.
It is dangerous to try to repair any part of
the air bag system yourself. Be sure to tell
anyone who works on your vehicle that it
has an air bag system.
Do not attempt to modify any part of your
air bag system. The air bag may inflate acci -
dentally or may not function properly if
modifications are made. Take your vehicle
to an authorized dealer for any air bag
system service. If your seat, including your
trim cover and cushion, needs to be
serviced in any way (including removal or
loosening/tightening of seat attachment
bolts), take the vehicle to an authorized
dealer. Only manufacturer approved seat
accessories may be used. If it is necessary
to modify the air bag system for persons
with disabilities, contact an authorized
dealer.
WARNING! (Continued)
4

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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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196STARTING AND OPERATING
NOTE:

Use of Climatized ULSD or Number 1 ULSD
Fuel results in a noticeable decrease in fuel
economy.
Climatized ULSD Fuel is a blend of Number 2
ULSD and Number 1 ULSD Fuels which
reduces the temperature at which wax crystals
form in fuel.
The fuel grade should be clearly marked on the
pump at the fuel station.
The engine requires the use of “ULSD Fuel”.
Use of incorrect fuel could result in engine and
exhaust system damage. Refer to “Fuel
Requirements” in “Technical Specifications”
for further information.
If climatized or diesel Number 1 ULSD fuel is
not available, and you are operating below
(20°F/-6°C), in sustained arctic conditions,
Mopar Premium Diesel Fuel Treatment (or
equivalent) is recommended to avoid gelling
(see Fuel Operating Range Chart).
Under some circumstances increased engine
noise may be audible in the seconds following
a cold start. This is most likely to occur when
using fuel that isnt blended for the ambient
temperature present. This may occur on an
unseasonably cold day or when a truck is fueled in a warmer climate and driven to a
colder climate. The noise can typically be
prevented by using Mopar Premium Diesel
Fuel Treatment as recommended (see Fuel
Operating Range Chart)..

Engine Oil Usage
Refer to “Dealer Service” in “Servicing And
Maintenance” for the correct engine oil
viscosity.

Winter Front Cover Usage
A winter front or cold weather cover is to be used in
ambient temperatures below 32°F (0°C), espe
-
cially during extended idle conditions. This cover is
equipped with four flaps for managing total grille
opening in varying ambient temperatures. If a
winter front or cold weather cover is to be used the
flaps should be left in the full open position to allow
air flow to the charge air cooler and automatic
transmission oil cooler. When ambient tempera -
tures drop below 0°F (-17°C) the four flaps need
to be closed. A suitable cold weather cover is avail -
able from your Mopar dealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the
battery temperature decreases to 0°F (-18°C). For
the same decrease in temperature, the engine
requires twice as much power to crank at the same RPM. The use of 120 Volts AC powered battery
blankets will greatly increase starting capability at
low temperatures. Suitable battery blankets are
available from an authorized Mopar dealer.

Engine Warm-Up
Avoid full throttle operation when the engine is
cold. When starting a cold engine, bring the
engine up to operating speed slowly to allow the
oil pressure to stabilize as the engine warms up.
NOTE:
High-speed, no-load running of a cold engine
can result in excessive white smoke and poor
engine performance. No-load engine speeds
should be kept under 1,000 RPM during the
warm-up period, especially in cold ambient
temperature conditions.
Your vehicle is equipped with an engine warm
up protection feature that may limit engine
performance after cold starting at low ambient
temperatures. The length of time engine speed
is limited is dependent upon engine coolant
temperature. Engine speed may be briefly
limited to 1,000 RPM after starting with coolant
temperature below freezing conditions, and
may be limited to 1,000 RPM for up to approxi
-
mately 2 minutes under more severe cold
conditions.

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200STARTING AND OPERATING
Operating Precautions
Avoid Overheating The Engine
The temperature of the engine coolant (anti -
freeze: a mixture of 50% ethylene-glycol and
50% water) must not exceed the normal range
of the temperature gauge 240°F (116°C) with
a 21 psi (145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze)
temperature indicated during operation will be
to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (anti -
freeze) temperature below the normal range on
the gauge 140°F (60°C) can be harmful to the
engine. Low engine coolant (antifreeze)
temperature can cause incomplete combustion
which allows carbon and varnish to form on
piston rings and injector nozzles. Also, the
unburned fuel can enter the crankcase, diluting
the lubricating oil and causing rapid wear to the
engine.
Cooling System Tips
To reduce potential for engine and transmission
overheating in high ambient temperature condi -
tions, take the following actions:
City Driving — When stopped, shift the trans -
mission into NEUTRAL and increase engine
idle speed.
Highway Driving — Reduce your speed.
Up Steep Hills — Select a lower transmission
gear.
Air Conditioning — Turn it off temporarily.
Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating
temperature, the minimum oil pressures
required are:
Do Not Operate The Engine With Failed Parts
All engine failures give some warning before the
parts fail. Be on the alert for changes in perfor -
mance, sounds, and visual evidence that the
engine requires service. Some important clues
are:
Engine misfiring or vibrating severely.
Sudden loss of power.
Unusual engine noises.
Fuel, oil or coolant leaks.
Sudden change, outside the normal oper -
ating range, in the engine operating tempera -
ture.
Excessive smoke.
Oil pressure drop.
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal
readings, shut the engine off immediately.
Failure to do so could result in immediate and
severe engine damage.

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STARTING AND OPERATING205
(Continued)
(Continued)
AUTOMATIC TRANSMISSION
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil-
dren, and do not leave a vehicle equipped
with Keyless Enter-N-Go in the ACC or ON/
RUN mode. A child could operate power
windows, other controls, or move the
vehicle.
Be sure the parking brake is fully disen
-
gaged before driving; failure to do so can
lead to brake failure and a collision.
Always fully apply the parking brake when
leaving your vehicle or it may roll and cause
damage or injury. Also, be certain to leave
the transmission in PARK. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the Brake System Warning Light remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.
WARNING! (Continued)
WARNING!
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accel -
erate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and your
foot is firmly pressing the brake pedal.
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.
Unintended movement of a vehicle could
injure those in or near the vehicle. As with
all vehicles, you should never exit a vehicle
while the engine is running. Before exiting a
vehicle, always come to a complete stop,
then apply the parking brake, shift the
transmission into PARK, turn the engine
OFF, and remove the key fob. When the
ignition is in the LOCK/OFF (key removal)
position, (or, with Keyless Enter-N-Go, when
the ignition is in the OFF mode) the trans -
mission is locked in PARK, securing the
vehicle against unwanted movement.
When leaving the vehicle, always make
sure the ignition is in the OFF mode,
remove the key fob from the vehicle, and
lock the vehicle.
Never use the PARK position as a substi -
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.
WARNING! (Continued)
5

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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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STARTING AND OPERATING211
NOTE:
Even if the transmission can be reset, we
recommend that you visit your authorized
dealer at your earliest possible convenience.
Your authorized dealer has diagnostic equip -
ment to assess the condition of your trans -
mission.
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 transmission is in DRIVE. For
example, if you set the transmission 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, 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.

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.
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.
5

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