engine JEEP WRANGLER 2015 JK / 3.G Workshop Manual

Key Ignition Park Interlock
This vehicle is equipped with a Key Ignition Park Inter-
lock which requires the transmission to be in PARK
before the ignition switch can be turned to the LOCK/
OFF (key removal) position. The key can only be re-
moved from the ignition when the ignition is in the
LOCK/OFF position, and once removed the transmission
is locked in PARK.
NOTE:If a malfunction occurs, the system will trap the
key in the ignition switch to warn you that this safety
feature is inoperable. The engine can be started and
stopped but the key cannot be removed until you obtain
service.
Brake/Transmission Shift Interlock System
This vehicle is equipped with a Brake Transmission Shift
Interlock System (BTSI) that holds the shift lever in PARK
unless the brakes are applied. To shift the transmission
out of PARK, the ignition switch must be turned to the
ON/RUN position (engine running or not) and the brake
pedal must be pressed.
Five-Speed Automatic Transmission — If
Equipped
The transmission gear position display (located in the
instrument cluster) indicates the transmission gear range.
You must press the brake pedal to move the shift lever
out of PARK (refer to “Brake/Transmission Shift Inter-
lock System” in this section). To drive, move the shift
lever from PARK or NEUTRAL to the DRIVE position.
The electronically-controlled transmission provides a
precise shift schedule. The transmission electronics are
self-calibrating; therefore, the first few shifts on a new
vehicle may be somewhat abrupt. This is a normal
condition, and precision shifts will develop within a few
hundred miles (kilometers).
5
STARTING AND OPERATING 431

Gear Ranges
DO NOT race the engine when shifting from PARK or
NEUTRAL into another gear range.
NOTE:
•After selecting any gear range, wait a moment to allow
the selected gear to engage before accelerating. This is
especially important when the engine is cold.
•If there is a need to restart the engine, be sure to cycle
the ignition to the LOCK/OFF position before restart-
ing. Transmission gear engagement may be delayed
after restarting the engine if the ignition is not cycled
to the LOCK/OFF position first.
PARK (P)
This range supplements the parking brake by locking the
transmission. The engine can be started in this range.
Never attempt to use PARK while the vehicle is in
motion. Apply the parking brake when leaving the
vehicle in this range.
When parking on a level surface, you may shift the
transmission into PARK first, and then apply the parking
brake.
When parking on a hill, apply the parking brake before
shifting the transmission to PARK, otherwise the load on
the transmission locking mechanism may make it diffi-
cult to move the shift lever out of PARK. As an added
precaution, turn the front wheels toward the curb on a
downhill grade and away from the curb on an uphill
grade.
NOTE:On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
5
STARTING AND OPERATING 433

WARNING!
•Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake
fully when parked to guard against vehicle move-
ment and possible injury or damage.
•Your vehicle could move and injure you and others
if it is not in PARK. Check by trying to move the
shift lever out of PARK with the brake pedal
released. Make sure the transmission is in PARK
before leaving the vehicle.
(Continued)
WARNING!(Continued)
•It is dangerous to shift out of PARK or NEUTRAL
if the engine speed is higher than idle speed. If
your foot is not firmly pressing the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and your foot is
firmly pressing the brake pedal.
(Continued)
434 STARTING AND OPERATING

WARNING!(Continued)
•Unintended movement of a vehicle could injure
those in or near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, always apply the
parking brake, shift the transmission into PARK,
turn the engine OFF, and remove the ignition key.
Once the key is removed, the transmission is
locked in PARK, securing the vehicle against un-
wanted movement.
•When leaving the vehicle, always remove the igni-
tion key from the vehicle and lock the vehicle.
(Continued)
WARNING!(Continued)
•Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Children should be
warned not to touch the parking brake, brake pedal
or the shift lever.
•Do not leave the ignition key in or near the vehicle
(or in a location accessible to children). A child
could operate power windows, other controls, or
move the vehicle.
5
STARTING AND OPERATING 435

CAUTION!
•Before moving the shift lever out of PARK, you
must turn the ignition switch from the LOCK/OFF
position to the ON/RUN position, and also press
the brake pedal. Otherwise, damage to the shift
lever could result.
•DO NOT race the engine when shifting from
PARK or NEUTRAL into another gear range, as this
can damage the drivetrain.
The following indicators should be used to ensure that
you have engaged the transmission into the PARK posi-
tion:
•When shifting into PARK, firmly move the shift lever
all the way forward and to the left until it stops and is
fully seated.
•Look at the transmission gear position display and
verify that it indicates the PARK position.
•With brake pedal released, verify that the shift lever
will not move out of PARK.
REVERSE (R)
This range is for moving the vehicle backward. Shift into
REVERSE only after the vehicle has come to a complete
stop.
NEUTRAL (N)
Use this range when the vehicle is standing for prolonged
periods with the engine running. The engine may be
started in this range. Apply the parking brake and shift
the transmission into PARK if you must leave the vehicle.
436 STARTING AND OPERATING

Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal 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 the current gear until the vehicle is brought to a stop.
After the vehicle has stopped, the transmission will
remain in second gear regardless of which forward gear
is selected. PARK, REVERSE, and NEUTRAL will con-
tinue 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 transmission.
In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the LOCK/OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no
longer detected, the transmission will return to normal
operation.
NOTE:Even if the transmission can be reset, we recom-
mend that you visit your authorized dealer at your
earliest possible convenience. Your authorized dealer has
diagnostic equipment to determine if the problem could
recur. If the transmission cannot be reset, authorized
dealer service is required.
438 STARTING AND OPERATING

Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fifth gear). The transmission will
automatically shift into Overdrive if the following con-
ditions are present:
•The shift lever is in the DRIVE position.
•Vehicle speed is sufficiently high.
•The driver is not heavily pressing the accelerator.
AUTOSTICK
AutoStick is a driver-interactive transmission feature
providing manual shift control, giving you more control
of the vehicle. AutoStick allows you to maximize engine
braking, eliminate undesirable upshifts and downshifts,
and improve overall vehicle performance.
This system can also provide you with more control
during passing, city driving, cold slippery conditions,
mountain driving, trailer towing, and many other situa-
tions.
Operation
When the shift lever is in the DRIVE position, the
transmission will operate automatically, shifting between
the five available gears. To engage AutoStick, simply tap
the shift lever to the right or left (+/-) while in the DRIVE
position. Tapping (-) to enter AutoStick mode will down-
shift the transmission to the next lower gear, while using
(+) to enter AutoStick mode will retain the current gear.
When AutoStick is active, the current transmission gear is
displayed in the instrument cluster.
In AutoStick mode, the transmission will shift up or
down when (+/-) is manually selected by the driver,
unless an engine lugging or overspeed condition would
5
STARTING AND OPERATING 439

result. It will remain in the selected gear until another
upshift or downshift is chosen, except as described
below.
•The transmission will automatically upshift when nec-
essary to prevent engine over-speed.
•Heavily pressing the accelerator pedal will generate an
automatic downshift (for improved acceleration) when
reasonable.
•The transmission will automatically downshift as the
vehicle slows (to prevent engine lugging) and will
display the current gear.
•The transmission will automatically downshift to first
gear when coming to a stop. After a stop, the driver
should manually upshift (+) the transmission as the
vehicle is accelerated.
•You can start out, from a stop, in first or second gear.
Tapping (+) (at a stop) will allow starting in second
gear. Starting out in second gear can be helpful in
snowy or icy conditions.
•The system will ignore attempts to upshift at too low
of a vehicle speed.
•Avoid using speed control when AutoStick is engaged.
•Transmission shifting will be more noticeable when
AutoStick is engaged.
NOTE:When the transfer case is in the 4L (Low) range,
the transmission will shift automatically (but no higher
than the displayed gear).
To disengage AutoStick mode, hold the shift lever to the
right (+) until#D#is once again displayed in the instru-
ment cluster. You can shift in or out of the AutoStick
mode at any time without taking your foot off the
accelerator pedal.
440 STARTING AND OPERATING

WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid, causing a collision or
personal injury.
FOUR–WHEEL DRIVE OPERATION (COMMAND-
TRAC I® OR ROCK-TRAC®)
WARNING!
Failure to engage a transfer case position completely
can cause transfer case damage or loss of power and
vehicle control. You could have a collision. Do not
drive the vehicle unless the transfer case is fully
engaged.
Operating Instructions/Precautions
The transfer case provides four mode positions:
•2H (Two-wheel drive high range)
•4H (Four-wheel drive high range)
•N (Neutral)
•4L (Four-wheel drive low range)
5
STARTING AND OPERATING 441

When operating your vehicle in 4L, the engine speed will
be approximately three times (four times for Rubicon
models) that of the 2H or 4H positions at a given road
speed. Take care not to overspeed the engine.
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
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 (N) position without first fully engaging
(Continued)
WARNING!(Continued)
the parking brake. The transfer case NEUTRAL (N)
position disengages both the front and rear drive
shaft from the powertrain, and will allow the vehicle
to roll, even if the automatic transmission is in PARK
(or manual transmission is in gear). The parking
brake should always be applied when the driver is
not in the vehicle.
Shift Positions
For additional information on the appropriate use of each
4WD system mode position, see the information below:
2H Position
This range is used for normal street and highway driving
on hard-surfaced roads.
5
STARTING AND OPERATING 443