2012 JEEP GRAND CHEROKEE light

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.
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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 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
—Rmeans radial construction
—Dmeans 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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These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes 1/16 in (2 mm). When the tread is worn to the
tread wear indicators, the tire should be replaced.
Life Of Tire
The service life of a tire is dependent upon various
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 an collision resulting
in serious injury or death.
Keep dismounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease, and gasoline.
1 — Worn Tire
2 — New Tire
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the outside temperature decreases, the tire pressure will
decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after the vehicle has not been driven for at least
three hours, or driven less than 1 mile (1.6 km) after a
three-hour period.Refer to “Tires – General Informa-
tion” in “Starting and Operating” for information on
how to properly inflate the vehicle’s tires.The tire
pressure will also increase as the vehicle is driven - this is
normal and there should be no adjustment for this
increased pressure.
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 recommendedcold tire pressure. Once the low tire pressure warning has
been illuminated, the tire pressure must be increased to
the recommended cold tire pressure in order for the Tire
Pressure Monitoring Telltale Light to be turned off. The
system will automatically update and the Tire Pressure
Monitoring Telltale Light will extinguish once the up-
dated 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 has a recommended cold
(parked for more than three hours) tire pressure of 33 psi
(227 kPa). If the ambient temperature is 68°F (20°C) and
the measured tire pressure is 28 psi (193 kPa), a tempera-
ture drop to 20°F (-7°C) will decrease the tire pressure to
approximately 24 psi (165 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 28 psi (193 kPa),
but the Tire Pressure Monitoring Telltale Light will still
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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 recommended cold tire pressure
value.
CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement
equipment that is not of the same size, type, and/or
style. Aftermarket wheels can cause sensor dam-
age. Do not use aftermarket tire sealants or balance
beads if your vehicle is equipped with a TPMS, as
damage to the sensors may result.
(Continued)
CAUTION! (Continued)
•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, or 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.
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•The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire gauge, even
if under-inflation has not reached the level to trigger
illumination of the Tire Pressure Monitoring Telltale
Light.
•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Premium 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 regularly
check the tire pressure in all of your tires and to maintain
the proper pressure.The Tire Pressure Monitor System (TPMS) consists of the
following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Various Tire Pressure Monitoring System Messages,
which display in the Electronic Vehicle Information
Center (EVIC), and a graphic displaying tire pressures
•Tire Pressure Monitoring Telltale Light
Tire Pressure Monitoring Low Pressure Warnings
The Tire Pressure Monitoring Telltale Light will
illuminate in the instrument cluster, and an au-
dible chime will be activated, when one or more of
the four active road tire pressures are low. In addition, the
EVIC will display one or more Low Pressure messages
(Left Front, Left Rear, Right Front, Right Rear) for a
minimum of five seconds, and a graphic display of the
pressure value(s) with the low tire(s) “flashing.” Refer to
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“Electronic Vehicle Information Center (EVIC)” in “Un-
derstanding Your Instrument Panel” for further informa-
tion.
NOTE:Your system can be set to display pressure units
in PSI, kPa, or BAR.
Should a low tire condition occur on any of the four
active road tire(s), you should stop as soon as possible,and inflate the low tire(s) that is “flashing” on the graphic
display to the vehicle’s recommended cold tire pressure.
The system will automatically update, the graphic dis-
play of the pressure value(s) will stop “flashing,” and the
Tire Pressure Monitoring Telltale Light will extinguish
once the updated tire pressure(s) 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.
SERVICE TPM SYSTEM Warning
The Tire Pressure Monitoring Telltale Light will flash on
and off for 75 seconds, and remain on solid when a
system fault is detected. The system fault will also sound
a chime. The EVIC will display a “SERVICE TPM SYS-
TEM” message for a minimum of five seconds. This
message is then followed by a graphic display, with “- -“
in place of the pressure value(s), indicating which Tire
Pressure Monitoring Sensor(s) is not being received.
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