engine Ram 3500 Chassis Cab 2018 Service Manual

2. As soon as you cycle the ignition switch to the ONposition, you will see the “Malfunction Indicator Light
(MIL)” symbol come on as part of a normal bulb check.
3. Approximately 15 seconds later, one of two things will happen:
• The MIL will flash for about ten seconds and then return
to being fully illuminated until you turn OFF the igni-
tion or start the engine. This means that your vehicle’s
OBD II system is not readyand you should notproceed
to the I/M station.
• The MIL will not flash at all and will remain fully
illuminated until you place the ignition in the off posi-
tion or start the engine. This means that your vehicle’s
OBD II system is readyand you can proceed to the I/M
station. If your OBD II system is
not ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive your vehicle
as you normally would in order for your OBD II system to
update. A recheck with the above test routine may then
indicate that the system is now ready.
Regardless of whether your vehicle’s OBD II system is
ready or not, if the MIL is illuminated during normal
vehicle operation you should have your vehicle serviced
before going to the I/M station. The I/M station can fail
your vehicle because the MIL is on with the engine
running.
158 GETTING TO KNOW YOUR INSTRUMENT PANEL

Towing With HSA
HSA will also provide assistance to mitigate roll back while
towing a trailer.
WARNING!
•If you use a trailer brake controller with your trailer,
the trailer brakes may be activated and deactivated
with the brake switch. If so, there may not be enough
brake pressure to hold both the vehicle and the
trailer on a hill when the brake pedal is released. In
order to avoid rolling down an incline while resum-
ing acceleration, manually activate the trailer brake
or apply more vehicle brake pressure prior to releas-
ing the brake pedal.
• HSA is not a parking brake. Always apply the
parking brake fully when exiting your vehicle. Also,
be certain to place the transmission in PARK.
• Failure to follow these warnings can result in a
collision or serious personal injury.
Disabling And Enabling HSA
This feature can be turned on or turned off. To change the
current setting, proceed as follows:
• If disabling HSA using your instrument cluster display,
refer to “Instrument Cluster Display” in “Getting To
Know Your Instrument Panel” for further information.
• If disabling HSA using Uconnect Settings, refer to
“Uconnect Settings” in “Multimedia” for further infor-
mation.
For vehicles not equipped with an instrument cluster
display, perform the following steps:
1. Center the steering wheel (front wheels pointing straight forward).
2. Shift the transmission into PARK.
3. Apply the parking brake.
4. Start the engine.
5. Rotate the steering wheel slightly more than one-half turn to the left.
164 SAFETY

6. Push the “ESC Off” button located in the lower switchbank below the climate control four times within 20
seconds. The “ESC Off Indicator Light” should turn on
and turn off two times.
7. Rotate the steering wheel back to center and then an additional slightly more than one-half turn to the right.
8. Turn the ignition to the OFF mode and then back to ON. If the sequence was completed properly, the “ESC Off
Indicator Light” will blink several times to confirm HSA
is disabled.
9. Repeat these steps if you want to return this feature to its previous setting.
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.
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SAFETY 165

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.
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.
WARNING!
• 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
(Continued)
WARNING! (Continued)
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 so
equipped.
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SAFETY 167

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.
• 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.
(Continued)
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 is turned to the ON mode. It
should go out with the engine running. If the
“ESC Activation/Malfunction Indicator Light” comes on
continuously with the engine running, a malfunction 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.
168 SAFETY

NOTE:
•The “ESC Activation/Malfunction Indicator Light” and
the “ESC OFF Indicator Light” come on momentarily
each time the ignition 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.
Electronic Roll Mitigation (ERM)
This system anticipates the potential for wheel lift by
monitoring the driver ’s steering wheel input and the speed
of the vehicle. When ERM determines that the rate of
change of the steering wheel angle and vehicle’s speed are
sufficient to potentially cause wheel lift, it then applies the
appropriate brake and may also reduce engine power to
lessen the chance that wheel lift will occur. ERM can only
reduce the chance of wheel lift occurring during severe or evasive driving maneuvers; it cannot prevent wheel lift
due to other factors, such as road conditions, leaving the
roadway, or striking objects or other vehicles.
NOTE:
ERM is disabled anytime the ESC is in “Full Off”
mode (if equipped). Refer to “Electronic Stability Control
(ESC)” in this section for a complete explanation of the
available ESC modes.
WARNING!
Many factors, such as vehicle loading, road conditions
and driving conditions, influence the chance that
wheel lift or rollover may occur. ERM cannot prevent
all wheel lift or roll overs, especially those that involve
leaving the roadway or striking objects or other ve-
hicles. The capabilities of an ERM-equipped vehicle
must never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety or the
safety of others.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an excessively
swaying trailer and will take the appropriate actions to
attempt to stop the sway. TSC will become active automati-
cally once an excessively swaying trailer is recognized.
5
SAFETY 169

NOTE:TSC cannot stop all trailers from swaying. Always
use caution when towing a trailer and follow the trailer
tongue weight recommendations. Refer to “Trailer Tow-
ing” in “Starting And Operating” for further information.
When TSC is functioning, the “ESC Activation/
Malfunction Indicator Light” will flash, the engine power
may be reduced and you may feel the brakes being applied
to individual wheels to attempt to stop the trailer from
swaying. TSC is disabled when the ESC system is in the
“Partial Off” or “Full Off” modes.
WARNING!
If TSC activates while driving, slow the vehicle down,
stop at the nearest safe location, and adjust the trailer
load to eliminate trailer sway.
Hill Descent Control (HDC) — If Equipped
HDC is intended for low speed off road driving while in
4WD Low Range. HDC maintains vehicle speed while
descending hills during various driving situations. HDC
controls vehicle speed by actively controlling the brakes.
HDC has three states:
1. Off (feature is not enabled and will not activate). 2. Enabled (feature is enabled and ready but activation
conditions are not met, or driver is actively overriding
with brake or throttle application).
3. Active (feature is enabled and actively controlling ve- hicle speed).
Enabling HDC
HDC is enabled by pushing the HDC switch, but the
following conditions must also be met to enable HDC:
• Driveline is in 4WD Low Range
• Vehicle speed is below 5 mph (8 km/h).
• Parking brake is released.
• Driver door is closed.
Activating HDC
Once HDC is enabled it will activate automatically if
driven down a grade of sufficient magnitude. The set speed
for HDC is selectable by the driver, and can be adjusted by
using the gear shift +/-. The following summarizes the
HDC set speeds:
HDC Target Set Speeds
• P = No set speed. HDC may be enabled but will not
activate
170 SAFETY

The ORC also includes diagnostics that will illuminate the
instrument panel Air Bag Warning Light if a malfunction is
detected that could affect the air bag system. The diagnos-
tics 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 intermittently 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.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.
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 compartment. The words “SRS
AIRBAG” or “AIRBAG” are embossed on the air bag
covers.
194 SAFETY

Enhanced Accident Response System
In the event of an impact, if the communication network
remains intact, and the power remains intact, depending
on the nature of the event, the ORC will determine whether
to have the Enhanced Accident Response System perform
the following functions:
•Cut off fuel to the engine.
• Flash hazard lights as long as the battery has power or
until the hazard light button is pressed. The hazard
lights can be deactivated by pressing the hazard light
button.
• Turn on the interior lights, which remain on as long as
the battery has power.
• Unlock the power door locks.
Enhanced Accident Response System Reset
Procedure
In order to reset the Enhanced Accident Response System
functions after an event, the ignition switch must be
changed from ignition START or ON/RUN to ignition OFF.
Carefully check the vehicle for fuel leaks in the engine
compartment and on the ground near the engine compart-
ment and fuel tank before resetting the system and starting
the engine.
Maintaining Your Air Bag System
WARNING!
•Modifications to any part of the air bag system could
cause it to fail when you need it. You could be
injured if the air bag system is not there to protect
you. Do not modify the components or wiring, in-
cluding adding any kind of badges or stickers to the
steering wheel hub trim cover or the upper right side
of the instrument panel. Do not modify the front
bumper, vehicle body structure, or add aftermarket
side steps or running boards.
• 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 accidentally 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 your authorized
(Continued)
5
SAFETY 203

SAFETY TIPS
Transporting Passengers
NEVER TRANSPORT PASSENGERS IN THE CARGO
AREA.
WARNING!
•Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build-up may
cause serious injury or death.
• It is extremely dangerous to ride in a cargo area,
inside or outside of a vehicle. In a collision, people
riding in these areas are more likely to be seriously
injured or killed.
• Do not allow people to ride in any area of your
vehicle that is not equipped with seats and seat belts.
• Be sure everyone in your vehicle is in a seat and
using a seat belt properly.
Exhaust Gas
WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO), which is colorless and odorless.
Breathing it can make you unconscious and can even-
tually poison you. To avoid breathing (CO), follow
these safety tips:
• Do not run the engine in a closed garage or in
confined areas any longer than needed to move your
vehicle in or out of the area.
• If you are required to drive with the trunk/liftgate/
rear doors open, make sure that all windows are
closed and the climate control BLOWER switch is set
at high speed. DO NOT use the recirculation mode.
• If it is necessary to sit in a parked vehicle with the
engine running, adjust your heating or cooling con-
trols to force outside air into the vehicle. Set the
blower at high speed.
The best protection against carbon monoxide entry into the
vehicle body is a properly maintained engine exhaust
system.
5
SAFETY 231