light JEEP WRANGLER 2012 JK / 3.G 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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Life Of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and the spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have a collision resulting
in serious injury or death.
Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the “Tire and Loading Infor-
mation” placard for the size designation of your tire. The
Load Index and Speed Symbol for your tire will be found
on the original equipment tire sidewall. See the Tire
Sizing Chart example found in the Tire Safety Informa-
tion section of this manual for more information relating
to the Load Index and Speed Symbol of a tire.
It is recommended to replace the two front tires or two
rear tires as a pair. Replacing just one tire can seriously
affect your vehicle’s handling. If you ever replace a
wheel, make sure that the wheel’s specifications match
those of the original wheels.
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The TPMS will warn the driver of a low tire pressure if
the tire pressure falls below the low pressure warning
threshold for any reason, including low temperature
effects, or natural pressure loss through the tire.
The TPMS will continue to warn the driver of low tire
pressure as long as the condition exists, and will not turn
off until the tire pressure is at or above recommended
cold placard pressure. Once the “Tire Pressure Monitor-
ing Telltale Light” has been illuminated, the tire pressure
must be increased to the recommended cold placard
pressure in order for the “Tire Pressure Monitoring
Telltale Light” to be turned OFF. The system will auto-
matically update and the “Tire Pressure Monitoring
Telltale Light” will extinguish once the updated tire
pressures have been received. The vehicle may need to be
driven for up to 20 minutes above 15 mph (24 km/h) to
receive this information.For example, your vehicle may have a recommended
cold (parked for more than three hours) air pressure of
35 psi (241 kPa). If the ambient temperature is 68°F (20°C)
and the measured tire pressure is 30 psi (207 kPa), a
temperature drop to 20°F (-7°C) will decrease the tire
pressure to approximately 26 psi (179 kPa). This tire
pressure is sufficiently low enough to turn ON the “Tire
Pressure Monitoring Telltale Light.” Driving the vehicle
may cause the tire pressure to rise to approximately
30 psi (207 kPa), but the “Tire Pressure Monitoring
Telltale Light” will still be ON. In this situation, the “Tire
Pressure Monitoring Telltale Light” will turn OFF only
after the tires have been inflated to the vehicle’s recom-
mended cold placard pressure value.
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CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. The TPMS pressures
have been established for the tire size equipped
on your vehicle. Undesirable system operation or
sensor damage may result when using replace-
ment equipment that is not of the same size, type,
and/or style. Aftermarket wheels can cause sensor
damage. Do not use aftermarket tire sealants or
balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.
•After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the valve
stem, which could damage the Tire Pressure Moni-
toring Sensor.NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire 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.
•The TPMS is not a substitute for proper tire mainte-
nance, 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 “Tire
Pressure Monitoring Telltale Light.”
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•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Base System
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim-mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.
NOTE:It is particularly important for you to check the
tire pressure in all of your tires regularly and to maintain
the proper pressure.
The Tire Pressure Monitor System (TPMS) consists of the
following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in the spare
wheel if the vehicle is equipped with a matching full size
spare wheel and tire assembly. The matching full size
spare tire can be used in place of any of the four road
tires. A low spare tire will not cause the “Tire Pressure
Monitoring Telltale Light” to illuminate or the chime to
sound. The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster,, a “LOW TIRE
PRESSURE” message will display in the EVIC, and
an audible chime will be activated when one or more of
the four active road tire pressures are low. Should this
occur, you should stop as soon as possible, check the
inflation pressure of each tire on your vehicle, and inflate
each tire to the vehicle’s recommended cold placard
pressure value. The system will automatically update
and the “Tire Pressure Monitoring Telltale Light” will
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extinguish once the updated tire pressures have been
received. The vehicle may need to be driven for up to
20 minutes above 15 mph (24 km/h) to receive this
information.
The “Tire Pressure Monitoring Telltale Light” will flash
on and off for 75 seconds, and will remain on solid when
a system fault is detected. The system fault will also
sound a chime. If the ignition key is cycled, this sequence
will repeat, providing the system fault still exists. A
system fault can occur by any of the following scenarios:
1. Jamming due to electronic devices or driving next to
facilities emitting the same Radio Frequencies as the TPM
sensors.
2. Installing some form of aftermarket window tinting
that affects radio wave signals.
3. Lots of snow or ice around the wheels or wheel
housings.4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors.
NOTE:
•If your vehicle is equipped with a matching full-size
spare wheel and tire assembly, it has a tire pressure
monitoring sensor, and can be monitored by the Tire
Pressure Monitoring System (TPMS). In the event that
the matching full-size spare tire is swapped with a low
pressure road tire, the next ignition key cycle will still
show the “Tire Pressure Monitoring Telltale Light” to
be ON, and a chime to sound. Driving the vehicle for
up to 20 minutes above 15 mph (24 km/h) will turn
OFF the “Tire Pressure Monitoring Telltale Light” as
long as none of the road tires are below the low
pressure warning threshold.
•If your vehicle is not equipped with a matching
full-size spare wheel and tire assembly, it does not
have a tire pressure monitoring sensor in the spare tire.
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