light JEEP WRANGLER 2015 JK / 3.G Repair Manual
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!BRAKE SYSTEM.......................468
!ELECTRONIC BRAKE CONTROL SYSTEM . . . .469
▫Anti-Lock Brake System (ABS)............469
▫Traction Control System (TCS)............471
▫Brake Assist System (BAS)...............471
▫Hill Start Assist (HSA).................472
▫Electronic Roll Mitigation (ERM)..........476
▫Electronic Stability Control (ESC)..........477
▫ESC Activation/Malfunction Indicator Light And
ESC OFF Indicator Light................483
▫Trailer Sway Control (TSC)..............484
▫Hill Descent Control (HDC) — If Equipped . . .485
!TIRE SAFETY INFORMATION.............487
▫Tire Markings........................487
▫Tire Identification Number (TIN)...........490
▫Tire Terminology And Definitions..........492
▫Tire Loading And Tire Pressure...........493
!TIRES — GENERAL INFORMATION........498
▫Tire Pressure........................498
▫Tire Inflation Pressures.................500
▫Tire Pressures For High Speed Operation . . . .501
▫Radial Ply Tires......................501
▫Tire Types...........................502
▫Run Flat Tires — If Equipped.............504
▫Spare Tires — If Equipped...............504
▫Tire Spinning........................507
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The “4WD Indicator Light” will illuminate when the
transfer case has been shifted into this mode.
Automatic Transmission — If Equipped
Start the vehicle with the shift lever in the PARK position
(vehicle can also be started in NEUTRAL). Apply the
brake before shifting to any driving range.
Normal Starting
NOTE:Normal starting of either a cold or a warm engine
is obtained without pumping or pressing the accelerator
pedal.
Cycle the ignition switch to the START position and
release when the engine starts. If the engine fails to start
within 10 seconds, cycle the ignition switch to the
LOCK/OFF position, wait 10 to 15 seconds, then repeat
the “Normal Starting” procedure.
Tip Start Feature — Automatic Transmission Only
Turn the ignition switch to the START position and
release it as soon as the starter engages. The starter motor
will continue to run, but will automatically disengage
itself when the engine is running. If the engine fails to
start, the starter will disengage automatically in 10 sec-
onds. If this occurs, turn the ignition switch to the LOCK
position, wait 10 to 15 seconds, then repeat the “Normal
Starting” procedure.
Extreme Cold Weather (Below –20°F Or−29°C)
To ensure reliable starting at these temperatures, use of
an externally powered electric engine block heater (avail-
able from your authorized dealer) is recommended.
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CAUTION!
Never drive with your foot resting on the clutch
pedal, or attempt to hold the vehicle on a hill with the
clutch pedal partially engaged, as this will cause
abnormal wear on the clutch.
NOTE:During cold weather, you may experience in-
creased effort in shifting until the transmission fluid
warms up. This is normal.
Shifting
Fully press the clutch pedal before shifting gears. As you
release the clutch pedal, lightly press the accelerator
pedal.
You should always use first gear when starting from a
standing position.
Shift Pattern
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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.
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The transfer case is intended to be driven in the 2H
position for normal street and highway conditions such
as hard-surfaced roads.
In the event that additional traction is required, the
transfer case 4H and 4L positions can be used to lock the
front and rear driveshafts together, forcing the front and
rear wheels to rotate at the same speed. The 4H and 4L
positions are intended for loose, slippery road surfaces
only and not intended for normal driving. Driving in the
4H and 4L positions on hard-surfaced roads will cause
increased tire wear and damage to the driveline compo-
nents. Refer to “Shifting Procedures” in this section for
further information on shifting into 4H or 4L.
The “4WD Indicator Light” (located in the instrument
cluster) alerts the driver that the vehicle is in four-wheel
drive, and the front and rear driveshafts are locked
together. The light will illuminate when the transfer case
is shifted into the 4H position.
NOTE:Do not attempt to shift when only the front or
rear wheels are spinning. The transfer case is not
equipped with a synchronizer, and the front and rear
driveshaft speeds must be equal for a shift to take place.
Shifting while the front or rear wheels are spinning at
different speeds can cause damage to the transfer case.
Four-Wheel Drive Shift Controls
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4H Position
This range locks the front and rear driveshafts together,
forcing the front and rear wheels to rotate at the same
speed. This range (4H) provides additional traction for
loose, slippery road surfaces and should not be used on
dry pavement.
The “4WD Indicator Light” (located in the instrument
cluster) will illuminate when the transfer case is shifted
into the 4H position.
N (Neutral) Position
This range disengages the front and rear driveshafts from
the powertrain. It is to be used for flat towing behind
another vehicle. Refer to “Recreational Towing” in “Start-
ing and Operating” for further information.
4L Position
This range locks the front and rear driveshafts together,
forcing the front and rear wheels to rotate at the same
speed. This range (4L) provides additional traction and
maximum pulling power for loose, slippery road surfaces
only. Do not exceed 25 mph (40 km/h).
CAUTION!
Exceeding 25 mph (40 km/h) while the transfer case is
engaged in 4L may result in an engine overspeed
condition and engine damage.
The “4WD Indicator Light” (located in the instrument
cluster) will illuminate when the transfer case is shifted
into the 4L position.
NOTE:When in 4WD, the “ESC Off Indicator Light” will
display in the instrument cluster.
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TRAC-LOK® REAR AXLE — IF EQUIPPED
The Trac-Lok® rear axle provides a constant driving force
to both rear wheels and reduces wheel spin caused by the
loss of traction at one driving wheel. If traction differs
between the two rear wheels, the differential automati-
cally proportions the usable torque by providing more
torque to the wheel that has traction.
Trac-Lok® is especially helpful during slippery driving
conditions. With both rear wheels on a slippery surface, a
slight application of the accelerator will supply maxi-
mum traction.
WARNING!
On vehicles equipped with a limited-slip differen-
tial, never run the engine with one rear wheel off the
ground. The vehicle may drive through the rear
wheel remaining on the ground and cause you to lose
control of your vehicle.
AXLE LOCK (TRU–LOK®) — RUBICON MODELS
The AXLE LOCK switch is located on the instrument
panel (to the left of the steering column).
Axle Lock Switch
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This feature will only activate when the following con-
ditions are met:
•Key in ignition, vehicle in 4L (Low) range.
•Vehicle speed should be 10 mph (16 km/h) or less.
To activate the system, press the bottom of the AXLE
LOCK switch once to lock the rear axle only (the “Rear
Axle Lock Indicator Light” will illuminate), press the
bottom of the switch again to lock the front axle (the
“Front Axle Lock Indicator Light” will illuminate). When
the rear axle is locked, pressing the switch again will lock
or unlock the front axle.
NOTE:The indicator lights will flash until the axles are
fully locked or unlocked.
To unlock the axles, press the top of the AXLE LOCK
switch.
Axle lock will disengage if the vehicle is taken out of 4L
(Low) range, or the ignition switch is turned to the OFF
position.
ELECTRONIC SWAY BAR DISCONNECT — IF
EQUIPPED
Your vehicle may be equipped with an electronic discon-
necting stabilizer/sway bar. This system allows greater
front suspension travel in off-road situations.
This system is controlled by the SWAY BAR switch
located on the instrument panel (to the left of the steering
column).
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Press the SWAY BAR switch to activate the system. Press
the switch again to deactivate the system. The “Sway Bar
Indicator Light” (located in the instrument cluster) will
illuminate when the bar is disconnected. The “Sway Bar
Indicator Light” will flash during activation transition, or
when activation conditions are not met. The stabilizer/
sway bar should remain in on-road mode during normal
driving conditions.
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. The front stabilizer bar
enhances vehicle stability and is necessary for main-
taining 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 or solid “Sway Bar Indicator
Light.” Once vehicle speed is reduced below 14 mph
(22 km/h), the system will once again attempt to
return to off-road mode.
Sway Bar Switch
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To disconnect the stabilizer/sway bar, shift to either 4H
or 4L and press the SWAY BAR switch to obtain the
off-road position. Refer to “Four-Wheel Drive Operation”
in “Starting and Operating” for further information. The
“Sway Bar 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
condition 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 on-road mode, press the SWAY BAR switch
again.
WARNING!
If the stabilizer/sway bar will not return to on-road
mode, the “Sway Bar Indicator Light” will flash in
the instrument cluster and vehicle stability is greatly
reduced. Do not attempt to drive the vehicle over
18 mph (29 km/h). Driving faster than 18 mph
(29 km/h) may cause loss of control of the vehicle,
which could result in serious injury. Contact your
local authorized dealer for assistance.
ON-ROAD DRIVING TIPS
Utility vehicles have higher ground clearance and a
narrower track to make them capable of performing in a
wide variety of off-road applications. Specific design
characteristics give them a higher center of gravity than
ordinary cars.
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