2015 Ram 1500 four wheel drive

after engine start up or illuminates during driving, it
means that the four-wheel drive system is not function-
ing properly and that service is required.
WARNING!
Always engage the parking brake when powering
down the vehicle if the “SVC 4WD Warning Light” is
illuminated. Not engaging the parking brake may
allow the vehicle to roll which may cause personal
injury or death.
NOTE:Do not attempt to make a shift while only the
front or rear wheels are spinning. This could cause
damage to driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD, 4WD
AUTO or 4WD LOCK positions at a given road speed.
Take care not to overspeed the engine and do not exceed
25 mph (40 km/h).
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type and circumference on each
wheel. Any difference in tire size can cause damage to the
drivetrain.
Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
WARNING!
You or others could be injured or killed if you leave
the vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
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WARNING!(Continued)
disengages both the front and rear drive shafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2WD
Rear-Wheel Drive High Range - This range is for normal
street and highway driving on dry hard surfaced roads.
4WD AUTO
Four-Wheel Drive Auto Range - This range sends power
to the rear wheels. The four–wheel drive system will be
automatically engaged when the vehicle senses a loss of
traction. Additional traction for varying road conditions.
4WD LOCK
Four-Wheel Drive Lock Range - This range maximizes
torque to the front driveshaft, forcing the front and rear
wheels to rotate at the same speed. Additional traction
for loose, slippery road surfaces only.
4WD LOW
Four-Wheel Drive Low Range - This range provides low
speed four-wheel drive. It maximizes torque to the front
driveshaft, forcing the front and rear wheels to rotate at
the same speed. This range provides additional traction
and maximum pulling power for loose, slippery road
surfaces only. Do not exceed 25 mph (40 km/h).
NEUTRAL (N)
Neutral - This range disengages both the front and rear
driveshafts from the powertrain. To be used for flat towing
behind another vehicle. Refer to “Recreational Towing” in
“Starting and Operating” for further information.
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CAUTION!
•Do not lock the front or rear axle on hard surfaced
roads. The ability to steer the vehicle is reduced
and damage to the drivetrain may occur when the
axles are locked on hard surfaced roads.
•Do not try to lock the rear axle if the vehicle is
stuck and the tires are spinning. You can damage
drivetrain components. Lock the rear axle before
attempting situations or navigating terrain, which
could possibly cause the vehicle to become stuck.
The locking axles are controlled by the axle locker switch.
The switch has three positions, AXLE UNLOCK, REAR
LOCK, and FRONT/REAR LOCK. Under normal driv-
ing conditions, the switch should be left in the AXLE
UNLOCK position. In the AXLE UNLOCK position, the
front and rear axles are unlocked. In the REAR LOCK
position, the rear axle is locked. In the FRONT/REAR
LOCK position, the front and rear axles are locked.
NOTE:Even when the axles are in the AXLE UNLOCK
position, the limited slip differential in the rear axle still
provides torque biasing capability for moderate low
traction environments.
During the command to lock the axle, the indicator light
will flash until the axle is locked. After the lock command
has been successfully executed, the light will remain on
solid.
To lock the rear axle, place the vehicle in 4LO. Refer to
“Four Wheel Drive Operation” in “Starting and Operat-
ing” for further information. Move the axle locker switch
position to REAR LOCK while traveling less than 3 mph
(5 km/h). The RR indicator light will remain on when the
rear axle is locked.
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WARNING!
Do not disconnect the stabilizer bar and drive on
hard surfaced roads or at speeds above 18 mph
(29 km/h), you may lose control of the vehicle, which
could result in serious injury or death. The front
stabilizer bar enhances vehicle stability and is nec-
essary for maintaining control of the vehicle. The
system monitors vehicle speed and will attempt to
reconnect the stabilizer bar at speeds over 18 mph
(29 km/h). This is indicated by a flashing off road
light and solid on road light. Once vehicle speed is
reduced below 14 mph (22 km/h), the system will
attempt to return to the Off-Road mode.
To disconnect the stabilizer/sway bar, shift to either 4HI
or 4LO as shown in “Four Wheel Drive Operation” and
press the right hand Off Road stabilizer/sway bar button
to obtain the Off-Road position. The amber indicator
light will flash until the stabilizer/sway bar has been
fully disconnected.
NOTE:The stabilizer/sway bar may be torque locked due
to left and right suspension height differences. This condi-
tion is due to driving surface differences or vehicle loading.
In order for the stabilizer/sway bar to disconnect/
reconnect, the right and left halves of the bar must be
aligned. This alignment may require that the vehicle be
driven onto level ground or rocked from side to side.
To return to the On-Road mode; press the left hand On
Road stabilizer/sway bar button .
WARNING!
If the stabilizer/sway bar will not return to On-Road
mode, vehicle stability is greatly reduced. Do not
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BRAKE SYSTEM
If power assist is lost for any reason (for example,
repeated brake applications with the engine off), the
brakes will still function. However, you will experience a
substantial increase in braking effort to stop the vehicle.
If either the front or rear hydraulic system loses normal
braking capability, the remaining system will still func-
tion with some loss of overall braking effectiveness. This
will be evident by increased pedal travel during applica-
tion, greater pedal force required to slow or stop, and
activation of the “Brake Warning Light” and the “ABS
Warning Light” (if equipped) during brake use.
Hydraulic Brake Assist — 2500/3500 Models Only
(Except Power Wagon)
The brake system power assist is provided by a hydro-boost
unit which shares fluid with the power steering system. You
may experience some clicking or hissing noises from the
hydro-boost system during hard braking conditions.
NOTE:Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake System
(ABS), Traction Control System (TCS), Brake Assist System
(BAS), Electronic Roll Mitigation (ERM), Hill Start Assist
(HSA), Electronic Stability Control (ESC), Trailer Sway
Control (TSC) and Hill Decent Control (HDC [Power
Wagon only]). All of the systems work together to enhance
vehicle stability and control in various driving conditions,
and are commonly referred to as ESC.
Anti-Lock Brake System (ABS)
The Four-Wheel Anti-Lock Brake System (ABS) is de-
signed to aid the driver in maintaining vehicle control
under adverse braking conditions. The system operates
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WARNING!
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 accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. ESC also cannot prevent accidents resulting
from loss of vehicle control due to inappropriate
driver input for the conditions. Only a safe, attentive,
and skillful driver can prevent accidents. The capa-
bilities of an ESC equipped vehicle must never be
exploited in a reckless or dangerous manner which
could jeopardize the user ’s safety or the safety of
others.
All Two-Wheel Drive Vehicles And Four-Wheel
Drive Vehicles In 2WD, 4WD AUTO, Or 4WD
LOCK Modes Can Choose The Following ESC
Operating Modes:
ESC On
This is the normal operating mode for ESC in 2WD/4WD
AUTO/4WD LOCK modes and in 2WD vehicles. When-
ever the vehicle is started or the transfer case (if
equipped) is shifted from 4WD LOW or Neutral, back to
4WD LOCK or 4WD AUTO, the ESC system will be in
this mode. This mode should be used for almost all
driving situations. ESC should only be turned to#ESC
Partial Off#or “ESC Full Off” for specific reasons as noted
below.
ESC Partial Off
This mode is entered by momentarily pressing the “ESC
Partial Off” switch. When in#Partial Off#mode, the TCS
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All Four-Wheel Drive Vehicles In 4WD AUTO And
4WD LOCK Modes Can Also Choose The
Following ESC Operating Mode. This Is The Only
Selectable ESC Operating Mode in 4WD LOW:
ESC Full Off
This mode is intended for off-road use when ESC stabil-
ity features could inhibit vehicle maneuverability due to
trail conditions. This mode is entered by pressing and
holding the “ESC Off” switch for five seconds when the
vehicle is stopped and the engine is running. After five
seconds, the “ESC Off Indicator Light” will illuminate.
Press and release the trip odometer button located on the
instrument cluster to clear this message.
NOTE:The “ESC OFF” message will display and the
audible chime will sound when the shift lever is placed
into the PARK position from any other position and then
moved out of the PARK position. This will occur even if
the message was previously cleared.
In this mode, ESC and TCS except for the “limited slip”
feature described in the TCS section are turned off until
the vehicle reaches a speed of 40 mph (64 km/h). At
40 mph (64 km/h) the system returns to “ESC Partial
Off” mode, described above. When the vehicle speed
drops below 35 mph (56 km/h) the ESC system reverts
back to#ESC Full Off#. ESC is off at low vehicle speeds so
that it will not interfere with off-road driving but ESC
function returns to provide the stability feature at speeds
above 40 mph (64 km/h). The “ESC Off Indicator Light”
will always be illuminated when ESC is in#ESC Partial
Off#and#ESC Full Off#. To turn ESC on again, momen-
tarily press the “ESC Off” switch. This will restore the
normal “ESC On” mode of operation.
“ESC Full Off” is the only operating mode for ESC in
4WD LOW. Whenever the vehicle is started in 4WD LOW
or the transfer case (if equipped) is shifted from 4WD
LOCK or NEUTRAL, to 4WD LOW, the ESC system will
be in this mode.
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•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Premium System
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim mounted electronic sensors to
monitor tire pressure levels. Sensors mounted to each
wheel as part of the valve stem transmit tire pressure
readings to the receiver module.
NOTE:It is particularly important for you to check the
tire pressure in all of the tires on your vehicle monthly
and to maintain the proper pressure.
The TPMS consists of the following components:
•Receiver module
•Four TPM sensors
•Various TPMS messages, which display in the Elec-
tronic Vehicle Information Center (EVIC)/Driver In-
formation Display (DID)
•TPM Telltale Light
The matching full size spare wheel and tire assembly (if
equipped) has a TPM sensor. The full size spare can be
used in place of any of the four road tires. A spare with a
pressure below the low-pressure limit will not cause the
“Tire Pressure Monitoring Telltale Light” to illuminate or
the chime to sound while it is stored in the spare tire
location.
Tire Pressure Monitoring Low Pressure Warnings
The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster and a chime
will sound when tire pressure is low in one or more of the
four active road tires. In addition, the EVIC/DID will
display a “LOW TIRE” message and a graphic showing
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