2019 Ram 4500 Chassis Cab brake

SAFETY 163
Electronic Brake Force Distribution (EBD)
This function manages the distribution of the braking torque
between the front and rear axles by limiting braking pressure
to the rear axle. This is done to prevent overslip of the rear
wheels to avoid vehicle instability, and to prevent the rear
axle from entering ABS before the front axle.
Brake System Warning Light
The red “Brake System Warning Light” will turn on when
the ignition is turned to the ON/RUN mode and may stay on
for as long as four seconds.
If the “Brake System Warning Light” remains on or comes on
while driving, it indicates that the brake system is not func-
tioning properly and that immediate service is required. If
the “Brake System Warning Light” does not come on when
the ignition is turned to the ON/RUN mode, have the light
repaired as soon as possible. Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking capa
-
bility during emergency braking maneuvers. The system
detects an emergency braking situation by sensing the rate
and amount of brake application and then applies optimum
pressure to the brakes. This can help reduce braking
distances. The BAS complements the anti-lock brake system
(ABS). Applying the brakes very quickly results in the best
BAS assistance. To receive the benefit of the system, you
must apply continuous braking pressure during the stop -
ping sequence, (do not “pump” the brakes). Do not reduce
brake pedal pressure unless braking is no longer desired.
Once the brake pedal is released, the BAS is deactivated.
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.
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164 SAFETY
Hill Start Assist (HSA)
The 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 pressure 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.
• Park brake must be off.
• 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 trans -
mission, if the clutch is pressed, HSA will remain active.
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.

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.
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166 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 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.

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 activationconditions 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.
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172 SAFETY
• N = 1.2 mph (2 km/h)
• D = 0.6 mph (1 km/h)
• 1st = 0.6 mph (1 km/h)
• 2nd = 1.2 mph (2 km/h)
• 3rd = 1.8 mph (3 km/h)
• 4th = 2.5 mph (4 km/h)
• 5th = 3.1 mph (5 km/h)
• 6th = 3.7 mph (6 km/h)
• 7th = 4.3 mph (7 km/h)
• 8th = 5.0 mph (8 km/h)
• 9th = 5.6 mph (9 km/h) – If Equipped
NOTE:
During HDC the +/- shifter input is used for HDC target
speed selection, but will not affect the gear chosen by the
transmission. When actively controlling HDC the transmis-
sion will shift appropriately for the driver-selected set speed
and corresponding driving conditions. Driver Override
The driver may override HDC activation with throttle or
brake application at anytime.
Deactivating HDC
HDC will be deactivated but remain available if any of the
following conditions occur:
• Driver overrides HDC set speed with throttle or brake
application.
• Vehicle speed exceeds 20 mph (32 km/h) but remains below 40 mph (64 km/h).
• Vehicle is on a downhill grade of insufficient magnitude, is on level ground, or is on an uphill grade.
• Vehicle is shifted to park.

SAFETY 173
Disabling HDC
HDC will be deactivated and disabled if any of the following
conditions occur:
• The driver pushes the HDC switch.
• The driveline is shifted out of 4WD Low Range.
• The parking brake is applied.
• Driver door opens.
• The vehicle is driven greater than 20 mph (32 km/h) forgreater than 70 seconds.
• The vehicle is driven greater than 40 mph (64 km/h) (HDC exits immediately).
• HDC detects excessive brake temperature. Feedback To The Driver
The instrument cluster has an HDC icon and the HDC switch
has an LED icon, which offers feedback to the driver about
the state HDC is in.
• The cluster icon and switch lamp will illuminate and
remain on solid when HDC is enabled or activated. This is
the normal operating condition for HDC.
• The cluster icon and switch lamp will flash for several seconds then extinguish when the driver pushes the HDC
switch but enable conditions are not met.
• The cluster icon and switch lamp will flash for several seconds then extinguish when HDC disables due to excess
speed.
• The cluster icon and switch lamp will flash when HDC deactivates due to overheated brakes. The flashing will
stop and HDC will activate again once the brakes have
cooled sufficiently.
WARNING!
HDC is only intended to assist the driver in controlling
vehicle speed when descending hills. The driver must
remain attentive to the driving conditions and is
responsible for maintaining a safe vehicle speed.
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