2012 JEEP WRANGLER Owners Manual

Hill Descent Control (HDC) – If Equipped
HDC is only intended for low speed off-road driving.
HDC maintains vehicle speed while descending hills in
off-road driving conditions by applying the brakes when
necessary.The symbol indicates the status of the Hill
Descent Control (HDC) feature. The lamp will
be on solid when HDC is armed. HDC can only
be armed when the transfer case is in the “4WD
LOW” position and the vehicle speed is less then 30 mph
(48 km/h). If these conditions are not met while attempt-
ing to use the HDC feature, the HDC indicator light will
flash on/off.
When enabled, HDC senses the terrain and activates
when the vehicle is descending a hill. HDC speed may be
adjusted by the driver to suit the driving conditions. The
speed corresponds to the transmission gear selected.Gear Approximate HDC Set
Speed
1st 1 mph (1.5 km/h)
2nd 2.5 mph (4 km/h)
3rd 4 mph (6.5 km/h)
4th 5.5 mph (9 km/h)
DRIVE 7.5 mph (12 km/h)
REVERSE 1 mph (1.5 km/h)
However, the driver can override HDC operation by
applying the brake to slow the vehicle down below the
HDC control speed. If more speed is desired during HDC
control, the accelerator pedal will increase vehicle speed
in the usual manner. When either the brake or the
accelerator is released, HDC will control the vehicle at the
original set speed.
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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
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NOTE:
•P (Passenger) - Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
•European-Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letterPis absent from this tire
size designation. Example: 215/65R15 96H.
•LT (Light Truck) - Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
•Temporary spare tires are spares designed for tempo-
rary emergency use only. Temporary high pressure
compact spare tires have the letter “T” or “S” molded
into the sidewall preceding the size designation. Ex-
ample: T145/80D18 103M.
•High flotation tire sizing is based on U.S. design
standards, and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.5
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Tire Sizing Chart
EXAMPLE:
Size Designation:
P= Passenger Car tire size based on U.S. design standards
....blank.... = Passenger Car tire based on European design standards
LT = Light Truck tire based on U.S. design standards
TorS= Temporary compact spare tire
31 = Overall diameter in inches (in)
215 = Section width in millimeters (mm)
65 = Aspect ratio in percent (%)
— Ratio of section height to section width of tire
10.5 = Section width in inches (in)
R = Construction code
—R means radial construction
— D means diagonal or bias construction
15 = Rim diameter in inches (in)
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EXAMPLE:
Service Description: 95= Load Index
— A numerical code associated with the maximum load a tire can carry
H = Speed Symbol
— A symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions
— The maximum speed corresponding to the speed symbol should only be achieved under
specified operating conditions (i.e., tire pressure, vehicle loading, road conditions, and
posted speed limits)
Load Identification: ....blank.... = Absence of any text on the sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL) = Extra load (or reinforced) tire
Light Load (LL) = Light load tire
C, D, E, F, G = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load — Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure — Maximum pressure indicates the maximum permissible cold tire inflation pressure for
this tire
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Tire Identification Number (TIN)
The TIN may be found on one or both sides of the tire,
however, the date code may only be on one side. Tires
with white sidewalls will have the full TIN, including the
date code, located on the white sidewall side of the tire.Look for the TIN on the outboard side of black sidewall
tires as mounted on the vehicle. If the TIN is not found on
the outboard side, then you will find it on the inboard
side of the tire.
EXAMPLE:
DOT MA L9 ABCD 0301
DOT = Department of Transportation
— This symbol certifies that the tire is in compliance with the U.S. Department of Transportation tire
safety standards, and is approved for highway use
MA = Code representing the tire manufacturing location (two digits)
L9 = Code representing the tire size (two digits)
ABCD = Code used by the tire manufacturer (one to four digits)
03 = Number representing the week in which the tire was manufactured (two digits)
—03 means the 3rd week.
01 = Number representing the year in which the tire was manufactured (two digits)
—01 means the year 2001
— Prior to July 2000, tire manufacturers were only required to have one number to represent the
year in which the tire was manufactured. Example: 031 could represent the 3rd week of 1981 or 1991
436 STARTING AND OPERATING

Tire Terminology And Definitions
TermDefinition
B-Pillar The vehicle B-Pillar is the structural member of the body located
behind the front door.
Cold Tire Inflation Pressure Cold tire inflation pressure is defined as the tire pressure after the
vehicle has not been driven for at least 3 hours, or driven less
than 1 mile (1.6 km) after sitting for a three hour period. Inflation
pressure is measured in units of PSI (pounds per square inch) or
kPa (kilopascals).
Maximum Inflation Pressure The maximum inflation pressure is the maximum permissible cold
tire inflation pressure for this tire. The maximum inflation pres-
sure is molded into the sidewall.
Recommended Cold Tire Inflation
Pressure Vehicle manufacturer’s recommended cold tire inflation pressure
as shown on the tire placard.
Tire Placard A paper label permanently attached to the vehicle describing the
vehicle’s loading capacity, the original equipment tire sizes and
the recommended cold tire inflation pressures.
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Tire Loading And Tire Pressure
Tire Placard Location
Tire Placard Location (Two-Door Models)
Tire Placard Location (Four-Door Models)
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