2007 JEEP GRAND CHEROKEE light

•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 high-pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter “T”
molded into the sidewall preceding the size designa-
tion. Example: 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
T= 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 un-
der specified operating conditions. (i.e. tire pressure, vehicle loading, road conditions,
and posted speed limits).
Load Identification:
....blank....= Absence of any text on sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL)= Extra Load (or Reinforced) Tire
Light Load= Light Load Tire
C,D,E= 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 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 accident result-
ing 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 Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after a vehicle has not been driven for more than
3 hours - and in outside ambient temperature.Refer to
the “Tires – General Information” in this section 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 TPM System 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 tem-
perature effects.
The TPM System 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 recom-
mended cold tire pressure. Once the low tire pressure
warning has been illuminated, the tire pressure must beincreased 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 10 minutes above
15 mph (24 km/h) to receive this information.
For example, your vehicle has a recommended cold
(parked for more than 3 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 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 Light” will still
be ON. In this situation, the “Tire Pressure Monitoring
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Telltale Light” will turn OFF only after the tires have been
inflated to the vehicle’s recommended cold tire pressure
value.
NOTE:Seasonal temperature changes will affect tire
pressure, and the TPM system will monitor the actual tire
pressure in the tire.
Base 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 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
•4 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.
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. The audible
chime will sound once every ignition cycle for each
condition that it detects. 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 tire pressure. The system
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will automatically update and the “Tire Pressure Moni-
toring Light” will extinguish once the updated tire pres-
sures have been received. The vehicle may need to be
driven for up to 10 minutes above 15 mph (24 km/h) to
receive this information. A low spare tire will not cause
the “Tire Pressure Monitoring Telltale Light” to illumi-
nate or the chime to sound.
The “Tire Pressure Monitoring Telltale Light” will flash
on and off for 60 seconds, and an audible chime will
sound when a system fault is detected. The flash cycle
will repeat every ten minutes, without an audible chime,
until the fault condition no longer exists. If the ignition
key is cycled, this sequence will repeat, providing the
system fault still exists.
NOTE:If your vehicle is equipped with a matching full
size spare tire, 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 sizespare 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 10 minutes above 15
mph (24 km/h) will turn OFF the “Tire Pressure Moni-
toring Telltale Light” as long as the spare tire or any other
road tire(s) are not below the low pressure warning
threshold.
NOTE:If your vehicle is equipped with a non-matching
full size spare tire, it does not have a tire pressure
monitoring sensor. Therefore, it will not be monitored by
the Tire Pressure Monitor System (TPMS). In the event
that the non-matching full size spare tire is swapped with
a low pressure road tire, each ignition key cycle will still
show the “Tire Pressure Monitoring Telltale Light” to be
ON, and a chime to sound. After the original road tire has
been properly repaired, and put back onto the vehicle in
place of the non-matching full size spare tire, the TPMS
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will update automatically, and the “Tire Pressure Moni-
toring Telltale Light” will be OFF as long as none of the
road tires are below the low pressure warning threshold.
The vehicle may need to be driven for up to 10 minutes
above 15 mph (24 km/h) to receive this information.
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 equip-
ment that is not of the same size, type, and/or style.
After-market 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.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the Tire Pressure Monitoring
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.
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