2014 JEEP GRAND CHEROKEE tires

The tire pressure will vary with temperature by about
1 psi (7 kPa) for every 12°F (6.5°C). This means that when
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 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
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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
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 equip-
ment that is not of the same size, type, and/or style.
(Continued)
CAUTION! (Continued)
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 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.
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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 LightTire 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 a LOW TIRE message in the tire
graphic display screen with the pressure value(s) and the
low tire(s) “flashing.” or in a different color. An Inflate to
XXX message will also be displayed. Refer to “Electronic
Vehicle Information Center (EVIC)” in “Understanding
Your Instrument Panel” for further information.
NOTE: Your system can be set to display pressure units
in PSI, kPa, or BAR.
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NOTE:Your system can be set to display pressure units
in PSI, kPa, or BAR.
If the ignition switch is cycled, this sequence will repeat,
providing the system fault still exists. If the system fault
no longer exists, the Tire Pressure Monitoring Telltale
Light will no longer flash, the SERVICE TPM SYSTEM
message will not be present, and a pressure value will be
displayed instead of dashes. 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.
The EVIC will also display a SERVICE TPM SYSTEM
message for a minimum of five seconds when a system
fault is detected possibly related an incorrect sensor
location fault. In this case, the SERVICE TPM SYSTEM
message is then followed by a graphic display, with
pressure values still shown. This indicates the pressure
values are still being received from the TPM Sensors but
they may not be located in the correct vehicle position.
However, the system still needs to be serviced as long as
the SERVICE TPM SYSTEM message exists.
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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 warn-
ing limit, upon the next ignition switch cycle, the Tire
Pressure Monitoring Telltale Light will remain ON, a
chime will sound, and the EVIC will still display a
“flashing” or different color pressure value in the
graphic display. An Inflate to XXXmessage will still
be displayed.
• 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 for 75 seconds and
then remain on solid. In addition, the EVIC will
display a “SERVICE TPM SYSTEM message for three
seconds and then display dashes (- -) in place of the pressure value. For each subsequent ignition switch
cycle, a chime will sound, the Tire Pressure Monitoring
Telltale Light will flash on and off for 75 seconds and
then remain on solid, and the EVIC will display a
SERVICE TPM SYSTEM
message for three seconds
and then display dashes (- -) in place of the pressure
value. 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.
In addition, the Tire Pressure Monitoring Telltale Light
will turn OFF and the graphic in the EVIC will display a
new pressure value instead of dashes (- -), 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.
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Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo.
The label also specifies maximum capacities of front and
rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle’s GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents
the actual tire size on your vehicle. Replacement tires
must be equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
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CAUTION!(Continued)
•Then, during the first 500 miles (805 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.
Perform the maintenance listed in the “Maintenance
Schedule.” Refer to “Maintenance Schedule” for the
proper maintenance intervals. When towing a trailer,
never exceed the GAWR or GCWR ratings.
WARNING!
Improper towing can lead to a collision. Follow these
guidelines to make your trailer towing as safe as
possible:
• Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have a collision.
• When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or dam-
age to brakes, axle, engine, transmission, steering,
suspension, chassis structure or tires.
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Towing Requirements — Trailer Brakes
WARNING!
•Do not connect trailer brakes to your vehicle’s hy-
draulic brake lines. It can overload your brake sys-
tem and cause it to fail. You might not have brakes
when you need them and could have an accident.
•Towing any trailer will increase your stopping dis-
tance. When towing you should allow for additional
space between your vehicle and the vehicle in front
of you. Failure to do so could result in an accident.
CAUTION!
If the trailer weighs more than 1,000 lbs (454 kg)
loaded, it should have its own brakes and they
should be of adequate capacity. Failure to do this
could lead to accelerated brake lining wear, higher
brake pedal effort, and longer stopping distances. •
Do not interconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
• An electronically actuated trailer brake controller is
required when towing a trailer with electronically
actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required.
• Trailer brakes are recommended for trailers over
1,000 lbs (454 kg) and required for trailers in excess of
1,653 lbs (750 kg).Towing Requirements — Tires
• Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
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