light JEEP WRANGLER UNLIMITED 2013 Repair Manual

▫ Traction Control System (TCS) ........... .457
▫ Brake Assist System (BAS) .............. .457
▫ Hill Start Assist (HSA) ................ .458
▫ Electronic Roll Mitigation (ERM) ......... .462
▫ Electronic Stability Control (ESC) ......... .463
▫ ESC Activation/Malfunction Indicator Light
And ESC OFF Indicator Light ........... .468
▫ Trailer Sway Control (TSC) ............. .469
▫ Hill Descent Control (HDC) – If Equipped . . .470
 TIRE SAFETY INFORMATION ............ .471
▫ Tire Markings ....................... .471
▫ Tire Identification Number (TIN) .......... .475
▫ Tire Terminology And Definitions ......... .476 ▫ Tire Loading And Tire Pressure .......... .477
 TIRES — GENERAL INFORMATION ........ .482
▫ Tire Pressure ....................... .482
▫ Tire Inflation Pressures ................ .483
▫ Tire Pressures For High Speed Operation . . . .485
▫ Radial Ply Tires ..................... .485
▫ All Season Tires – If Equipped ........... .485
▫ Summer Or Three Season Tires – If Equipped. .486
▫ Snow Tires ......................... .486
▫ Spare Tire Matching Original Equipped Tire
And Wheel – If Equipped ............... .487
▫ Compact Spare Tire – If Equipped ........ .487
▫ Full Size Spare – If Equipped ............ .488
5 STARTING AND OPERATING 407

STARTING PROCEDURES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
WARNING!• When leaving the vehicle, always remove the key
fob from the ignition and lock your vehicle.
• 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. Manual Transmission – If Equipped
Apply the parking brake, place the shift lever in NEU-
TRAL, and press the clutch pedal before starting the
vehicle. This vehicle is equipped with a clutch interlock-
ing ignition system. It will not start unless the clutch
pedal is pressed to the floor.
Four-Wheel Drive Models Only
In 4L mode, this vehicle will start regardless of whether
or not the clutch pedal is pressed to the floor. This feature
enhances off-road performance by allowing the vehicle to
start when in 4L without having to press the clutch pedal.
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.410 STARTING AND OPERATING

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.
Recommended Vehicle Shift Speeds
To utilize your manual transmission efficiently for both
fuel economy and performance, it should be upshifted as
listed in recommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. When heavily
loaded or pulling a trailer these recommended up-shift
speeds may not apply.
Manual Transmission Shift Speeds in MPH (KM/H)
Engine Speeds 1 to 22to
3 3to
4 4to
5 5to
6
3.6L Accel. 15 (24)24
(39) 34
(55) 47
(76) 56
(90)
Cruise 10 (16)19
(31) 27
(43) 37
(60) 41
(66)
NOTE: Vehicle speeds shown in the chart above are for
2H and 4H only, vehicle speeds in 4L would be signifi-
cantly less.
5
STARTING AND OPERATING 415
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When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) shift control (refer to “Electronic Range
Select (ERS) Operation” in this section) to select a lower
gear range. Under these conditions, using a lower gear
range will improve performance and extend transmission
life by reducing excessive shifting and heat buildup.
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 engine OFF.
4. Wait approximately 10 seconds.
5 STARTING AND OPERATING 425

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. This is accom-
plished by simply moving the shift lever to one of these
positions. 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 components.
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 only the front or rear wheels are spinning
can cause damage to the transfer case.
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.
5 STARTING AND OPERATING 429

WARNING!You or others could be injured if you leave the vehicle
unattended with the transfer case in the N (Neutral)
position without first fully engaging the parking brake.
The transfer case N (Neutral) position disengages both
the front and rear driveshaft from the powertrain, and
will allow the vehicle to move regardless of the trans-
mission position. 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
transfer case mode position, see the information below:
2H Position
This range is used for normal street and highway driving
on hard-surfaced roads. 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 same430 STARTING AND OPERATING

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).
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.
Shifting Procedure
2H to 4H or 4H to 2H
Shifting between 2H and 4H can be made 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 complet-
ing the shift. Apply a constant force when shifting the
transfer case lever. 4H to 4L or 4L to 4H
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift an
automatic transmission into NEUTRAL (N), or press the
clutch pedal on a manual transmission. While the vehicle is
coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer case
lever firmly to the desired position. Do not pause with the
transfer case in N (Neutral). Once the shift is completed,
place the automatic transmission into DRIVE or release the
clutch pedal on a manual transmission.
NOTE: Shifting into or out of 4L is possible with the
vehicle completely stopped; however, difficulty may occur
due to the mating teeth not being properly aligned. Several
attempts may be required for clutch teeth alignment and
shift completion to occur. The preferred method is with the
vehicle rolling at 2 to 3 mph (3 to 5 km/h). Avoid
attempting to engage or disengage 4L with the vehicle
moving faster than 2 to 3 mph (3 to 5 km/h).
5 STARTING AND OPERATING 431

WARNING!
Failure to engage a 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.
TRAC-LOKREAR 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.
432 STARTING AND OPERATING
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AXLE LOCK (TRU–LOK  ) — RUBICON MODELS
The AXLE LOCK switch is located on the instrument
panel (to the left of the steering column). 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.Axle Lock Switch
5 STARTING AND OPERATING 433

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).
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 Switch434 STARTING AND OPERATING