wheel size JEEP WRANGLER 2012 JK / 3.G Owners Manual

OCCUPANT RESTRAINTS
Some of the most important safety features in your
vehicle are the restraint systems:
•Three-point lap and shoulder belts for the driver and
all passengers
•Advanced Front Air Bags for driver and front passen-
ger
•Supplemental Seat-Mounted Side Air Bags (SAB) — if
equipped
•An energy-absorbing steering column and steering
wheel
•Knee bolsters/blockers for front seat occupants
•Front seat belts incorporate pretensioners that may
enhance occupant protection by managing occupant
energy during an impact event
•All seat belt systems (except the driver’s) include
Automatic Locking Retractors (ALRs), which lock the
seat belt webbing into position by extending the belt
all the way out and then adjusting the belt to the
desired length to restrain a child seat or secure a large
item in a seat — if equipped
Please pay close attention to the information in this
section. It tells you how to use your restraint system
properly, to keep you and your passengers as safe as
possible.
If you will be carrying children too small for adult-sized
seat belts, the seat belts or the Lower Anchors and Tether
for CHildren (LATCH) feature also can be used to hold
infant and child restraint systems. For more information
on LATCH, refer to Lower Anchors and Tether for
CHildren (LATCH).
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THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 43

WARNING!
Ignoring the Air Bag Warning Light in your instru-
ment panel could mean you won’t have the air bags
to protect you in a collision. If the light does not come
on as a bulb check when the ignition is first turned
on, stays on after you start the vehicle, or if it comes
on as you drive, have an authorized dealer service the
air bag system immediately.
Driver And Passenger Advanced Front Air Bag
Inflator Units
The Driver and Passenger Advanced Front Air Bag
Inflator Units are located in the center of the steering
wheel and on the right side of the instrument panel.
When the ORC detects a collision requiring the Ad-
vanced Front Air Bags, it signals the inflator units. A large
quantity of non-toxic gas is generated to inflate the
Advanced Front Air Bags. Different air bag inflation ratesare possible, based on the collision type and severity. The
steering wheel hub trim cover and the upper right side of
the instrument panel separate and fold out of the way as
the air bags inflate to their full size. The air bags fully
inflate in about 50 to 70 milliseconds. This is about half of
the time it takes to blink your eyes. The air bags then
quickly deflate while helping to restrain the driver and
front passenger.
The Advanced Front Air Bag gas is vented through the
vent holes in the sides of the air bag. In this way, the air
bags do not interfere with your control of the vehicle.Supplemental Seat-Mounted Side Air Bags (SAB)
Inflator Units — If Equipped
The Supplemental Seat-Mounted Side Air Bags Inflator
Units (if equipped) are designed to activate only in
certain side collisions.
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THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 65

tires of a different size than the size indicated on the
vehicle placard or tire inflation pressure label, you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a Tire Pressure Monitoring System
(TPMS) that illuminates a low tire pressure telltale when
one or more of your tires is significantly under-inflated.
Accordingly, when the low tire pressure telltale illumi-
nates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving
on a significantly under-inflated tire causes the tire to
overheat and can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life, and may affect
the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver ’s responsibility to
maintain correct tire pressure, even if under-inflation has
not reached the level to trigger illumination of the TPMS
low tire pressure telltale.Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will flash for
approximately one minute and then remain continuously
illuminated. This sequence will continue upon subse-
quent vehicle start-ups as long as the malfunction exists.
When the malfunction indicator is illuminated, the sys-
tem may not be able to detect or signal low tire pressure
as intended. TPMS malfunctions may occur for a variety
of reasons, including the installation of replacement or
alternate tires or wheels on the vehicle that prevent the
TPMS from functioning properly. Always check the
TPMS malfunction telltale after replacing one or more
tires or wheels on your vehicle, to ensure that the
replacement or alternate tires and wheels allow the TPMS
to continue to function properly.
276 UNDERSTANDING YOUR INSTRUMENT PANEL

CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Do not use tire sealant from a can or
balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.
24. Odometer / Trip Odometer Display Area
The odometer display shows the total distance the vehicle
has been driven. The trip odometer shows individual trip
mileage. Refer to “Odometer / Trip Odometer / ECO
(Fuel Saver Indicator) Button” for additional information.
U.S. Federal regulations require that upon transfer of
vehicle ownership, the seller certify to the purchaser the
correct mileage that the vehicle has been driven. If your
odometer needs to be repaired or serviced, the repair
technician should leave the odometer reading the same
as it was before the repair or service. If s/he cannot do so,
then the odometer must be set at zero, and a sticker must
be placed in the door jamb stating what the mileage was
before the repair or service. It is a good idea for you to
make a record of the odometer reading before the repair/
service, so that you can be sure that it is properly reset, or
that the door jamb sticker is accurate if the odometer
must be reset at zero.
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UNDERSTANDING YOUR INSTRUMENT PANEL 277

▫Brake Assist System (BAS) .............. 420
▫ Hill Start Assist (HSA) ................ 420
▫ Electronic Roll Mitigation (ERM) ......... 424
▫ Electronic Stability Control (ESC) ......... 425
▫ ESC Activation/Malfunction Indicator Light
And ESC Off Indicator Light ............ 429
▫ Trailer Sway Control (TSC) ............. 430
▫ Hill Descent Control (HDC) – If Equipped . . 431
 Tire Safety Information ................. 432
▫ Tire Markings ....................... 432
▫ Tire Identification Number (TIN) ......... 436
▫ Tire Terminology And Definitions ......... 437
▫ Tire Loading And Tire Pressure .......... 438
Tires — General Information ............. 443
▫ Tire Pressure ....................... 443
▫ Tire Inflation Pressures ................ 444
▫ Tire Pressures For High-Speed Operation . . . 445
▫ Radial-Ply Tires ..................... 446
▫ Spare Tire Matching Original Equipped Tire
And Wheel – If Equipped .............. 446
▫ Compact Spare Tire – If Equipped ........ 447
▫ Full Size Spare – If Equipped ............ 447
▫ Limited-Use Spare – If Equipped ......... 448
▫ Tire Spinning ....................... 448
▫ Tread Wear Indicators ................. 449
▫ Life Of Tire ........................ 450
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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 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 transmission 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.
392 STARTING AND OPERATING

CAUTION!
If the “Brake Warning Light” remains on with the
parking brake released, a brake system malfunction
is indicated. Have the brake system serviced by an
authorized dealer immediately.
ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type, and tires must be properly inflated to produce
accurate signals for the computer.
WARNING!
Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low speed self-
test at about 12 mph (20 km/h). If for any reason your
foot is on the brake when the vehicle reaches 12 mph
(20 km/h), this check will be delayed until 25 mph
(40 km/h).
The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation; this is normal.
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STARTING AND OPERATING 417

Enabling HDC
1. Shift the transfer case into 4WD LOW range. Refer to
“Four-Wheel Drive Operation” in “Starting and Operat-
ing” for further information.
2. Press the “Hill Descent” button. The “Hill Descent
Control Indicator Light” in the instrument cluster will
turn on solid.
NOTE:If the transfer case is not in 4WD LOW range,
the “Hill Descent Control Indicator Light” will flash for
five seconds and HDC will not be enabled.
Disabling HDC
1. Press the “Hill Descent” button or shift the transfer
case out of 4WD LOW range. The “Hill Descent Control
Indicator” light in the instrument cluster will turn off.TIRE SAFETY INFORMATION
Tire Markings
1 — U.S. DOT Safety
Standards Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and Temperature Grades
432 STARTING AND OPERATING

Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause a collision. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized dealer for radial tire repairs.
Spare Tire Matching Original Equipped Tire And
Wheel – If Equipped
Your vehicle may be equivalent with a spare tire and
wheel in look and function as the original equipment tire
and wheel found on the front or rear axle of your vehicle.
This spare tire may be used in the tire rotation for your vehicle. If your vehicle has this option refer to an
authorized tire dealer for the recommended tire rotation
pattern.
If your vehicle is not equipped with an original equip-
ment tire and wheel as a spare, a non-matching tempo-
rary emergency use spare may be equipped with your
vehicle. Temporary use spares are engineered to be used
only with your vehicle. Your vehicle may be equipped
with one of the following types of non-matching tempo-
rary use spares; compact, full size, or limited-use. Do not
install more than one non-matching temporary use spare
tire/wheel on the vehicle at any given time.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact, full size or limited-use temporary spare
installed. Damage to the vehicle may result.
446 STARTING AND OPERATING

Compact Spare Tire – If Equipped
The compact spare is for temporary emergency use only.
You can identify if your vehicle is equipped with a
compact spare by looking at the spare tire description on
the Tire and Loading Information Placard located on the
driver ’s side door opening or on the sidewall of the tire.
Compact spare tire descriptions begin with the letter “T”
or “S” preceding the size designation. Example: T145/
80D18 103M.
T, S = Temporary Spare Tire
Since this tire has limited tread life the original equip-
ment tire should be repaired (or replaced) and reinstalled
on your vehicle at the first opportunity.
Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare tire.
Do not install more than one compact spare tire and
wheel on the vehicle at any given timeWARNING!
Compact spares are for temporary emergency use
only. With these spares, do not drive more than
50 mph (80 km/h). Temporary use spares have limited
tread life. When the tread is worn to the tread wear
indicators, the temporary use spare tire needs to be
replaced. Be sure to follow the warnings, which
apply to your spare. Failure to do so could result in
spare tire failure and loss of vehicle control.
Full Size Spare – If Equipped
The full size spare is for temporary emergency use only.
This tire may look like the original equipped tire on the
front or rear axle of your vehicle, but it is not. This spare
tire may have limited tread life. When the tread is worn
to the tread wear indicators, the temporary use full size
spare tire needs to be replaced. Since it is not the same as
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