2007 JEEP GRAND CHEROKEE warning light

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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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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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. The audible
chime will sound once every ignition cycle for each
condition that it detects. In addition, the Electronic
Vehicle Information Center (EVIC) will display one or
more Low Pressure messages (Left Front, Left Rear, Right
Front, Right Rear) for 3 seconds, and a graphic display of
the pressure value(s) with the low tire(s) flashing. Refer
to “Electronic Vehicle Information Center (EVIC)” in
Section 4 of this manual.
NOTE:If your vehicle is equipped with a matching full
size spare tire, a low matching full size spare tire will set
the “SPARE LOW PRESSURE” text message, but it will
not cause the “Tire Pressure Monitoring Telltale Light” to
illuminate or the chime to sound.NOTE:If your vehicle is equipped with a non-matching
full size spare tire, a low non-matching full size spare tire
will not display any text messages, or cause the “Tire
Pressure Monitoring Telltale Light” to illuminate or the
chime to sound.
NOTE:Your system can be set to display pressure units
in PSI, kPa, or BAR.
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If the ignition key 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, theSERVICE TIRE PRESS.
SYSTEMtext message will no longer display, and a
pressure value will be displayed instead of dashes.
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 size
spare 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, a chime to sound, a
Low Pressure message to appear in the EVIC, and the
graphic display will still show the low tire pressure value
flashing. Driving the vehicle for up to 10 minutes above
15 mph (24 km/h) will turn OFF the “Tire Pressure
Monitoring Telltale Light” as long as the matching full
size spare tire or any other road tire(s) are not below thelow pressure warning threshold. The EVIC will display a
“Spare Low Pressure” text message, and the graphic
display will show a new tire pressure value in place of
the flashing low tire pressure value.
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, every ignition key cycle will still
show the “Tire Pressure Monitoring Telltale Light” to be
ON, a chime to sound, a Low Pressure message to appear
in the EVIC, and the graphic display will still show the
low tire pressure value flashing. 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 will update the graphic display on the EVIC
with a new tire pressure value instead of the flashing low
tire pressure value, and the “Tire Pressure Monitoring
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Telltale Light” will be OFF as long as no road tire(s) 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, nor 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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CAUTION!
Damage to the fuel system or emission control
system could result from using an improper fuel cap
(gas cap). A poorly fitting cap could let impurities
into the fuel system. Also, a poorly fitting after-
market cap can cause the MIL (Malfunction Indica-
tor Light) to illuminate, due to fuel vapors escaping
from the system.
CAUTION!
A poorly fitting gas cap may cause the Malfunction
Indicator Light to turn on.
CAUTION!
To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.
NOTE:When the fuel nozzle “clicks” or shuts off, the
fuel tank is full.
WARNING!
•Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank filled.
•Never add fuel when the engine is running. This
is in violation of most state and federal fire
regulations and will cause the malfunction indi-
cator light to turn on.
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NOTE:Tighten the gas cap about 1/4 turn until you
hear one click. This is an indication that cap is properly
tightened.
If the gas cap is not tighten properly, the Malfunction
Indicator Light will come on. Be sure the gas cap is
tightened every time the vehicle is refueled.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
“CHECK GASCAP” message will be displayed in theEVIC (Electronic Vehicle Information Center). Refer to
“Electronic Vehicle Information Center” in Section 4 of
this manual. Tighten the fuel filler cap until a “clicking”
sound is heard. This is an indication that the fuel filler
cap is properly tightened. Refer to “Onboard Diagnostic
System — OBDII” in Section 7 of this manual for more
information.
CAUTION!
Damage to the fuel system or emission control
system could result from using an improper fuel
tank filler cap (gas cap). A poorly fitting cap could let
impurities into the fuel system.
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