2012 JEEP GRAND CHEROKEE light

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
—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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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.
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. (Refer to the paragraph on
“Tread Wear Indicators”). Refer to the “Tire and Loading
Information” 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
Information 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.
It is recommended you contact your original equipment
or an authorized tire dealer with any questions you may
have on tire specifications or capability. Failure to use
equivalent replacement tires may adversely affect the
safety, handling, and ride of your vehicle.
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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 recommended cold tire placard 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 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 has a recommended cold
(parked for more than three hours) tire placard 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 temperature 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
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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 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.
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 regularly
check the tire pressure in all of your tires, and to maintain
the proper pressure. The TPMS consists of the following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A low spare tire will not cause the Tire Pressure Moni-
toring Telltale Light to illuminate, a warning message to
appear, 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 instru-
ment cluster for 5 seconds, 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
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will automatically update and the Tire Pressure Monitor-
ing 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.
The Tire Pressure Monitoring Telltale Light will flash on
and off for 75 seconds, and remain on solid when a
system fault is detected. In addition, a “SERVICE TPM
SYSTEM” message may be displayed for approximately
5 seconds when a system fault is detected, and a chime
will sound. If the ignition switch is cycled, this sequence
will repeat, providing the system fault still exists. The
Tire Pressure Monitoring Telltale Light will turn off when
the fault condition no longer exists. A system fault can
occur by any of the following:
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:
There is no tire pressure monitoring sensor in
the spare tire. The TPMS will not be able to monitor the
tire pressure. If you install the spare tire, in place of a
road tire, that has a pressure below the low-pressure
warning limit, upon the next ignition switch cycle, a
chime will sound, a “LOW TIRE PRESSURE” message
will be displayed in the instrument cluster for a mini-
mum of five seconds, and the Tire Pressure Monitoring
Telltale Light will turn ON. After driving the vehicle for
up to 20 minutes above 15 mph (24 km/h), the Tire
Pressure Monitoring Telltale Light will flash on and off
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for 75 seconds and then remain on solid. In addition, a
“SERVICE TPM SYSTEM” message will be displayed for
a minimum of five seconds. For each subsequent ignition
switch cycle, a chime will sound, a “SERVICE TPM
SYSTEM” message will be displayed for a minimum of
five seconds, and the Tire Pressure Monitoring Telltale
Light will flash on and off for 75 seconds and then remain
on solid. Once you repair or replace the original road tire,
and reinstall it on the vehicle in place of the spare tire, the
TPMS will update automatically and the Tire Pressure
Monitoring Telltale Light will turn OFF, as long as no tire
pressure is below the low-pressure warning limit in any
of the four active road tires. The vehicle may need to be
driven for up to 20 minutes above 15 mph (24 km/h) in
order for the TPMS to receive this information.Premium System – If Equipped
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
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