2017 Ram 2500 Ac system

gear range will improve performance and extend transmis-
sion life by reducing excessive shifting and heat buildup.
If the transmission temperature exceeds normal operating
limits, the powertrain controller will modify the transmis-
sion shift schedule and expand the range of torque con-
verter clutch engagement. This is done to prevent trans-
mission damage due to overheating.
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 sig-
nificant additional 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 operation may be
modified depending on engine and transmission tempera-
ture as well as vehicle speed. This feature improves warm
up time of the engine and transmission to achieve maxi-
mum efficiency. Engagement of both the torque converter
clutch and the top overdrive gear are inhibited until the
transmission fluid is warm (refer to the “Note” under
“Torque Converter Clutch” in this section). During ex-
tremely cold temperatures (-16°F [-27°C] or below), opera-
tion may briefly be limited to first and direct gears only.
Normal operation will resume once the transmission tem-
perature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for ab-
normal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in fourth gear regardless of which forward gear is selected.
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 trans-
mission.
5
STARTING AND OPERATING 409

If One Or More Of The Following Shift Conditions Are
Not Met:
1. The indicator light for the current position will remainON.
2. The newly selected position indicator light will continue to flash.
3. The transfer case will notshift.
NOTE: Before retrying a selection, make certain that all
the necessary requirements for selecting a new transfer
case position have been met. To retry the selection, turn the
control switch back to the current position, wait five
seconds, and retry selection. To find the shift requirements,
refer to the Shifting Procedure for your transfer case,
located in this section.
The “SVC 4WD Warning Light” monitors the electronic
shift four-wheel drive system. If this light remains on after
engine start up or illuminates during driving, it means that
the four-wheel drive system is not functioning 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.
NOTE: Do not attempt to make a shift while only the front
or rear wheels are spinning, as this can cause damage to
driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD 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.
5
STARTING AND OPERATING 419

WARNING!
You or others could be injured or killed if you leave the
vehicle unattended with the transfer case in the NEU-
TRAL position without first fully engaging the park-
ing brake. The transfer case NEUTRAL position disen-
gages both the front and rear drive shafts from the
powertrain and will allow the vehicle to roll, even if
the transmission is in PARK. The parking brake
should always be applied when the driver is not in the
vehicle.
Shifting Procedure
NOTE:
•If any of the requirements to select a new transfer case
position have not been met, the transfer case will not
shift. The position indicator light for the previous posi-
tion will remain ON and the newly selected position
indicator light will continue to flash until all the require-
ments for the selected position have been met. To retry a
shift: return the control switch back to the original
position, make certain all shift requirements have been
met, wait five seconds and try the shift again. •
If all the requirements to select a new transfer case
position have been met, the current position indicator
light will turn OFF, the selected position indicator light
will flash until the transfer case completes the shift.
When the shift is complete, the position indicator light
for the selected position will stop flashing and remain
ON.
2WD To 4WD LOCK
Rotate the 4WD control switch to the desired position.
Shifts between 2WD and 4WD LOCK can be done with the
vehicle stopped or in motion. With the vehicle in motion,
the transfer case will engage/disengage faster if you mo-
mentarily release the accelerator pedal after turning the
control switch. If the vehicle is stopped, the ignition switch
must be in the ON position with the engine either running
or off. This shift cannot be completed if the ignition switch
is in the ACC position.
NOTE: The four-wheel drive system will not allow shifts
between 2WD/4WD LOCK if the front and/or rear wheels
are spinning (no traction). In this situation, the selected
position indicator light will flash and the original position
indicator light will remain ON. At this time, reduce speed
and stop spinning the wheels to complete the shift.
420 STARTING AND OPERATING

Electronically Shifted Transfer Case (Five-Position
Switch) — If Equipped
This is an electronic shift transfer case and is operated by
the 4WD Control Switch (Transfer Case Switch), which is
located on the instrument panel.
This electronically shifted transfer case provides five mode
positions:
•Two-Wheel Drive High Range (2WD)
• Four-Wheel Drive Automatic High Range (4WD AUTO)
• Four-Wheel Drive Lock High Range (4WD LOCK) •
Four-Wheel Drive Low Range (4WD LOW)
• Neutral (NEUTRAL)
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 High Range — This range sends
power to the front wheels. The four-wheel drive system
will be automatically engaged when the vehicle senses a
loss of traction. Additional traction for varying road con-
ditions.
4WD LOCK
Four-Wheel Drive Lock High Range — This range maxi-
mizes 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.
Five-Position/On-Demand Transfer Case
422 STARTING AND OPERATING

Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights (4WD, 4LOW,
and 4WD AUTO) are located in the instrument cluster and
indicate the current and desired transfer case selection.
When you select a different transfer case position, the
indicator lights will do the following:
If All Of The Following Shift Conditions Are Met:
1. The current position indicator light will turn OFF.
2. The selected position indicator light will flash until thetransfer case completes the shift.
3. When the shift is complete, the indicator light for the selected position will stop flashing and remain ON.
If One Or More Of The Following Shift Conditions Are
Not Met:
1. The indicator light for the current position will remain ON.
2. The newly selected position indicator light will continue to flash.
3. The transfer case will notshift. NOTE:
Before retrying a selection, make certain that all the
necessary requirements for selecting a new transfer case
position have been met. To retry the selection, turn the
control switch back to the current position, wait five
seconds, and retry selection. To find the shift requirements,
refer to the Shifting Procedure for your transfer case,
located in this section.
The “SVC 4WD Warning Light” monitors the electronic
shift four-wheel drive system. If this light remains on after
engine start up or illuminates during driving, it means that
the four-wheel drive system is not functioning 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.
424 STARTING AND OPERATING

2WD To 4WD AUTO Or 4WD LOCK
Rotate the 4WD Control Switch to the desired position.
Shifts between 2WD and 4WD AUTO and 4WD LOCK can
be done with the vehicle stopped or in motion. With the
vehicle in motion, the transfer case will engage/disengage
faster if you momentarily release the accelerator pedal after
turning the control switch. If the vehicle is stopped, the
ignition switch must be in the ON position with the engine
either running or OFF. This shift cannot be completed if the
ignition switch is in the ACC position.
NOTE:The four-wheel drive system will not allow shifts
between 2WD and 4WD AUTO/4WD LOCK if the front
and/or rear wheels are spinning (no traction). In this
situation, the selected position indicator light will flash and
the original position indicator light will remain ON. At this
time, reduce speed and stop spinning the wheels to com-
plete the shift.
2WD Or 4WD AUTO Or 4WD LOCK To 4WD LOW
NOTE: When shifting into or out of 4WD LOW some gear
noise may be heard. This noise is normal and is not
detrimental to the vehicle or occupants. Shifting can be performed with the vehicle rolling 2 to
3 mph (3 to 5 km/h) or completely stopped. Use either of
the following procedures:
Preferred Procedure
1. With the engine running, slow the vehicle to 2 to 3 mph
(3 to 5 km/h).
2. Shift the transmission into NEUTRAL.
3. While still rolling, rotate the 4WD control switch to the desired position.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.
Alternate Procedure
1. Bring the vehicle to complete stop.
2. With the ignition switch in the ON position and the engine running, shift the transmission into NEUTRAL.
3. Rotate the 4WD control switch to the desired position.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.
426 STARTING AND OPERATING

Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights (4WD and
4LOW) are located in the instrument cluster and indicate
the current and desired transfer case selection. When you
select a different transfer case position, the indicator lights
will do the following:
If All Of The Following Shift Conditions Are Met:
1. The current position indicator light will turn OFF.
2. The selected position indicator light will flash until thetransfer case completes the shift.
3. When the shift is complete, the indicator light for the selected position will stop flashing and remain ON.
If One Or More Of The Following Shift Conditions Are
Not Met:
1. The indicator light for the current position will remain ON.
2. The newly selected position indicator light will continue to flash.
3. The transfer case will notshift. NOTE:
Before retrying a selection, make certain that all the
necessary requirements for selecting a new transfer case
position have been met. To retry the selection, push the
current position, wait five seconds, and retry selection. To
find the shift requirements, refer to the Shifting Procedure
for your transfer case, located in this section.
The “SVC 4WD Warning Light” monitors the electronic
shift four-wheel drive system. If this light remains on after
engine start up or illuminates during driving, it means that
the four-wheel drive system is not functioning 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.
5
STARTING AND OPERATING 429

When the shift is complete, the position indicator light
for the selected position will stop flashing and remain
ON.
2WD To 4WD LOCK
Push the desired position on the 4WD control switch to
shift the transfercase. Shifts between 2WD and 4WD LOCK
can be done with the vehicle stopped or in motion. With
the vehicle in motion, the transfer case will engage/
disengage faster if you momentarily release the accelerator
pedal after selecting the desired position on the control
switch. If the vehicle is stopped, the ignition must be in the
ON position with the engine either running or off. This
shift cannot be completed if the ignition switch is in the
ACC position.
NOTE: The four-wheel drive system will not allow shifts
between 2WD/4WD LOCK if the front and/or rear wheels
are spinning (no traction). In this situation, the selected
position indicator light will flash and the original position
indicator light will remain ON. At this time, reduce speed
and stop spinning the wheels to complete the shift. 2WD Or 4WD LOCK To 4WD LOW
NOTE:
When shifting into or out of 4WD LOW some gear
noise may be heard. This noise is normal and is not
detrimental to the vehicle or occupants.
Shifting can be performed with the vehicle rolling 2 to
3 mph (3 to 5 km/h) or completely stopped. Use either of
the following procedures:
Preferred Procedure
1. With the engine running, slow the vehicle to 2 to 3 mph (3 to 5 km/h).
2. Shift the transmission into NEUTRAL.
3. While still rolling, push the desired position on the transfer case control switch.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.
Alternate Procedure
1. Bring the vehicle to complete stop.
2. With the ignition switch in the ON position and the engine running, shift the transmission into NEUTRAL.
5
STARTING AND OPERATING 431