engine RAM CHASSIS CAB 2019 Service Manual

160 GETTING TO KNOW YOUR INSTRUMENT PANEL
NOTE:
If you crank or start the engine, you will have to start this test
over.
2. As soon as you cycle the ignition switch to the ON posi -
tion, 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 ignition or
start the engine. This means that your vehicle's OBD II
system is not ready and you should not proceed to the I/M
station.
• The MIL will not flash at all and will remain fully illumi -
nated until you place the ignition in the off position or start
the engine. This means that your vehicle's OBD II system
is ready and you can proceed to the I/M station. If your OBD II system is not ready, you should see an autho -
rized 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 oper -
ation 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.

SAFETY 165
Towing With HSA
HSA will also provide assistance to mitigate roll back while
towing a trailer. 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 “Ucon -
nect Settings” in “Multimedia” for further information.
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.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 resuming acceleration,
manually activate the trailer brake or apply more
vehicle brake pressure prior to releasing 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 colli -
sion or serious personal injury. 4

166 SAFETY
6. Push the “ESC Off” button located in the lower switch
bank 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 addi -
tional 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 power 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 applying the
brake of the appropriate wheel(s) to assist in counteracting
the oversteer or understeer condition. Engine 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 appro -
priate for the steering wheel position.
• Understeer — when the vehicle is turning less than appro -
priate for the steering wheel position.

168 SAFETY
(Continued)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 illumi -
nate. 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. Multiple momentary
button pushed may be required to return to ESC On. 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.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 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. WARNING! (Continued)

SAFETY 169
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 igni -
tion 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 an authorized dealer as
soon as possible to have the problem diagnosed and
corrected.
The “ESC Activation/Malfunction Indicator Light” (located
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 condi -
tions.
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.WARNING!
• In the ESC “Full Off” mode, the engine torque reduc -
tion and stability features are disabled. Therefore,
enhanced vehicle stability offered by the ESC system is
unavailable. In an emergency evasive maneuver, the
ESC system will not engage to assist in maintaining
stability. ESC “Full Off” mode is intended for
off-highway or off-road use only.
• The 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 all accidents,
including those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro -
planing. ESC also cannot prevent collisions. 4

170 SAFETY
The “ESC OFF Indicator Light” indicates the
customer has elected to have the Electronic Stability
Control (ESC) in a reduced mode.
Electronic Roll Mitigation (ERM)
This system anticipates the potential for wheel lift by moni -
toring 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 maneu -
vers; 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. 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.
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 Towing” in
“Starting And Operating” for further information. 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 vehicles. 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.

SAFETY 171
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.
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 vehicle
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 acti -
vate.
• R = 0.6 mph (1 km/h)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.
4

184 SAFETY
Trailer Tire Pressure System Not Configured
A “Trailer Tire Pressure System Not Configured” message
will be displayed in the Instrument Cluster when a trailer
number is selected that does not have configuration values
entered for the (Number of Tires, Number of Axles, SET
Target Tire Pressure, trailer TPM sensor ID's).
To correct this condition the (Number of Tires, Number of
Axles, and SET Target Tire Pressure) values must be entered
in the radio for the trailer number selected. The trailer
sensors must also be paired to the trailer. Refer to the “Ucon -
nect Settings” in “Multimedia” for further information.
Trailer Sensors Detected Do Not Match Active Trailer
The “Trailer Sensors Detected Do Not Match Active Trailer”
message will be displayed in the Instrument Cluster when
the trailer sensors being received by the TTPM module do
match the trailer sensors paired to the current trailer number
selected. This message will be displayed when the sensors
being received completely match the sensors paired to
another trailer number configured in the TTPM module.
To correct this condition, the correct trailer number must be
selected in the radio. Refer to the “Uconnect Settings” in
“Multimedia” for further information. Tire Fill Alert
This feature notifies the user when the placard tire pressure
is attained while inflating or deflating the tire.
The customer may choose to disable or enable the Tire Fill
Alert feature through use of the customer settings in the
radio.
NOTE:
• Only one tire can be filled at a time when using the Tire Fill
Alert system.
• The Tire Fill Alert feature cannot be entered if an existing
TPM system fault is set to “active” or if the system is in
deactivation mode (if equipped).
The system will be activated when the TPM receiver module
detects a change in tire pressure. The ignition must be in the
RUN mode, with the transmission in PARK (P).
NOTE:
It is not required to have the engine running to enter Tire Fill
Alert mode.
The hazard lamps will come on to confirm the vehicle is in
Tire Fill Alert mode.

SAFETY 203
Air Bag Warning Light
The ORC monitors the readiness of the elec -
tronic 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 posi -
tion 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 disconnected prior to deployment.
The ORC turns on the Air Bag Warning Light in the instru -
ment 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 illuminate 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 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. 4

212 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 (If Equipped)
• Cut off battery power to the electric motor (If Equipped)
• Flash hazard lights as long as the battery has power
• Turn on the interior lights, which remain on as long as the
battery has power or for 15 minutes from the intervention
of the Enhanced Accident Response System.
• Unlock the power door locks.
Your vehicle may also be designed to perform any of these
other functions in response to the Enhanced Accident
Response System:
• Turn off the Fuel Filter Heater, Turn off the HVAC Blower
Motor, Close the HVAC Circulation Door • Cut off battery power to the:
• Engine
• Electric Motor (if equipped)
• Electric power steering
• Brake booster
• Electric park brake
• Automatic transmission gear selector
• Horn
• Front wiper
• Headlamp washer pump
NOTE:
After an accident, remember to cycle the ignition to the STOP
(OFF/LOCK) position and remove the key from the ignition
switch to avoid draining the battery. Carefully check the
vehicle for fuel leaks in the engine compartment and on the
ground near the engine compartment and fuel tank before
resetting the system and starting the engine. If there are no
fuel leaks or damage to the vehicle electrical devices (e.g.
headlights) after an accident, reset the system by following
the procedure described below. If you have any doubt,
contact an authorized dealer.