tire pressure JEEP PATRIOT 2008 1.G Owner's Manual

The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
check tire pressure. DO NOT make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under-inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure.” Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least three hours, or driven less than 1
mi (1.6 km) after a three hour period. The cold tire
inflation pressure must not exceed the maximum infla-
tion pressure molded into the tire sidewall.
Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire Placard Location
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Tire pressures change by approximately 1 psi (7 kPa) per
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicleloading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
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DO NOT install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare.
DO NOT install more than one compact spare tire/wheel
on the vehicle at any given time.
CAUTION!
Because of the reduced ground clearance, DO NOT
take your vehicle through an automatic car wash with
the compact spare installed. Damage to the vehicle
may result.
Limited-Use Spare — If Equipped
The limited-use spare tire is for temporary emergency
use on your vehicle. This tire is identified by a limited-
use spare tire warning label located on the limited-use
spare tire and wheel assembly. This tire may look like theoriginal equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited-use spare
tire affects vehicle handling. Since it is not the same tire,
replace (or repair) the original tire and reinstall on the
vehicle at the first opportunity.
WARNING!
The limited-use spare tires are for emergency use
only. Installation of this limited-use spare tire affects
vehicle handling. With this tire, DO NOT drive more
than 50 mph (80 km/h). Keep inflated to the cold tire
inflation pressure listed on either your tire placard or
limited-use spare tire and wheel assembly. Replace
(or repair) the original tire at the first opportunity
and reinstall it on your vehicle. Failure to do so could
result in loss of vehicle control.
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Many states have laws requiring tire replacement at this
point.
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 an accident 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.
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 service description and load identification will be
found on the original equipment tire. Failure to use
equivalent replacement tires may adversely affect the
safety, handling, and ride of your vehicle. We recommend
that you contact your original equipment or an autho-
rized tire dealer with any questions you may have on tire
specifications or capability.
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type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels and contribute to
a smooth, quiet ride.
Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible, if desired. The reason(s) for any rapid or unusual
wear should be corrected before rotating. The suggested
rotation method is the “forward-cross” shown in the
diagram below.TIRE PRESSURE MONITORING SYSTEM (TPMS)
— IF EQUIPPED
•
The Tire Pressure Monitor System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold placard pressure.
•The tire pressure will vary with temperature by about
1 psi (6.9 kPa) for every 12°F (6.5°C). This means that
when the outside temperature decreases, the tire pres-
sure 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 mi
(1 km) after a three hour period. The cold tire inflation
pressure must not exceed the maximum inflation
pressure molded into the tire sidewall. Refer to “Tires
– General Information” in this section for information
on how to properly inflate the vehicle’s tires. The tire
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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 warn-
ing limit 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 the
recommended cold placard pressure. Once the low tire
pressure warning (Tire Pressure Monitoring Telltale
Light) illuminates, you must increase the tire pressure
to the recommended cold placard pressure in order for
the Tire Pressure Monitoring Telltale Light to turn off.
The system will automatically update and the Tire
Pressure Monitoring Telltale Light will turn off once
the system receives the updated tire pressures. Thevehicle may need to be driven for up to 10 minutes
above 15 mph (25 km/h) in order for the TPMS to
receive this information.
For example, your vehicle may have a recom-
mended cold (parked for more than three hours)
placard pressure of 30 psi (207 kPa). If the ambient
temperature is 68°F (20°C) and the measured tire
pressure is 27 psi (186 kPa), a temperature drop to
20°F (-7°C) will decrease the tire pressure to ap-
proximately 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 27
psi (186 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 are inflated to the vehicle’s
recommended cold placard pressure value.
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CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warnings have been established for the tire size
equipped on your vehicle. Undesirable system
operation or sensor damage may result when us-
ing replacement 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 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.
•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.
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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 — If Equipped
This is the TPMS warning indicator located in the
instrument cluster.
The TPMS uses wireless technology with wheel rim
mounted electronic sensors to monitor tire pressure lev-
els. 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 the tires on your vehicle regularly
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
The Tire Pressure Monitoring Telltale Light will illumi-
nate in the instrument cluster, 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 Monitor-
ing 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 (25 km/h) to receive
this information.
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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. If the ignition key 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
with 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. 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:Your vehicle is equipped with a compact spare
wheel and tire assembly.
1. The compact spare tire does not have a tire pressure
monitoring sensor. Therefore, the TPMS will not monitor
the tire pressure in the compact spare tire.
2. If you install the compact spare tire in place of a road
tire that has a pressure below the low-pressure warning
limit, upon the next ignition key cycle, a chime will
sound and the Tire Pressure Monitoring Telltale Light
will still turn ON due to the low tire.
3. However, after driving the vehicle for up to 10 min-
utes above 15 mph (25 km/h), the Tire Pressure Moni-
toring Telltale Light will flash on and off for 75 seconds
and then remain on solid.
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4. For each subsequent ignition key cycle, a chime will
sound and the Tire Pressure Monitoring Telltale Light
will flash on and off for 75 seconds and then remain on
solid.
5. Once you repair or replace the original road tire and
reinstall it on the vehicle in place of the compact 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 10 minutes above 15 mph (25
km/h) in order for the TPMS to receive this information.
Premium System — If Equipped
The TPMS uses wireless technology with wheel rim
mounted electronic sensors to monitor tire pressure lev-
els. 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 TPMS consists of the following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Three Trigger Modules (mounted in three of the four
wheel wells)
•Various Tire Pressure Monitoring System Messages,
which display in the Electronic Vehicle Information
Center (EVIC)
•Yellow Tire Pressure Monitoring Telltale Light
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