2012 JEEP GRAND CHEROKEE light

•Tire Pressure Monitoring Telltale Light
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. In addition, the
EVIC will display a “LOW TIRE PRESSURE” message for
a minimum of five seconds, and a graphic display of the
pressure value(s) with the low tire(s) “flashing.” Refer to
“Electronic Vehicle Information Center (EVIC)” in “Un-
derstanding Your Instrument Panel” for further informa-
tion.
NOTE: Your system can be set to display pressure units
in PSI, kPa, or BAR.
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Should a low tire condition occur on any of the four
active road tire(s), you should stop as soon as possible,
and inflate the low tire(s) that is “flashing” on the graphic
display to the vehicle’s recommended cold tire pressure.
The system will automatically update, the graphic dis-
play of the pressure value(s) will stop “flashing,” and the
Tire Pressure Monitoring Telltale Light will extinguish
once the updated tire pressure(s) 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.
SERVICE TPM SYSTEM Warning
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. The EVIC will display a “SERVICE TPM SYS-
TEM” message for a minimum of five seconds. This
message is then followed by a graphic display, with “- -“
in place of the pressure value(s), indicating which Tire
Pressure Monitoring Sensor(s) is not being received.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
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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 aSERVICE TPM SYSTEM
message for a minimum of five seconds when a system
fault is detected possibly related to an incorrect sensor
location fault. In this case, the SERVICE TPM SYSTEMmessage 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.
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, the Tire Pres-
sure Monitoring Telltale Light will remain ON, a chime
will sound, and the EVIC will still display a “flashing”
pressure value in the graphic display. 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 mes-
sage for five seconds and then display dashes (- -) in
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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 sec-
onds and then remain on solid, and the EVIC will display
aSERVICE TPM SYSTEM message for five 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.General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
•This device may not cause harmful interference.
•This device must accept any interference received,
including interference that may cause undesired
operation.
The tire pressure sensors are covered under one of the
following licenses:
United States ................... MRXC4W4MA4
Canada ..................... 2546A-C4W4MA4
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FUEL REQUIREMENTS
3.6L Engine
This engine is designed to meet all emis-
sions regulations and provide excellent
fuel economy and performance when us-
ing high-quality unleaded “regular” gaso-
line having an octane rating of 87. The use
of premium gasoline is not recommended,
as it will not provide any benefit over regular gasoline in
these engines.
5.7L Engine
This engine is designed to meet all emis-
sions regulations and provide satisfactory
fuel economy and performance when us-
ing high-quality unleaded gasoline having
an octane range of 87 to 89. The manufac-
turer recommends the use of 89 octane for optimum performance. The use of premium gasoline is
not recommended, as it will not provide any benefit over
regular gasoline in these engines.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required. Poor quality gasoline can cause problems such
as hard starting, stalling, and hesitations. If you experi-
ence these symptoms, try another brand of gasoline
before considering service for the vehicle.
Over 40 auto manufacturers worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) which define fuel properties
necessary to deliver enhanced emissions, performance,
and durability for your vehicle. The manufacturer recom-
mends the use of gasolines that meet the WWFC speci-
fications if they are available.
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Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline.”
Reformulated gasoline contains oxygenates and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer supports the use of reformulated gaso-
line. Properly blended reformulated gasoline will pro-
vide excellent performance and durability of engine and
fuel system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as Ethanol. Fuels blended with oxygenates
may be used in your vehicle.
CAUTION!
DO NOT use gasoline containing Methanol or gaso-
line containing more than 10% Ethanol. Use of these
blends may result in starting and driveability prob-
lems, damage critical fuel system components, cause
emissions to exceed the applicable standard, and/or
cause the “Malfunction Indicator Light” to illumi-
nate. Pump labels should clearly communicate if a
fuel contains greater than 10% Ethanol.
Problems that result from using gasoline containing
Methanol or gasoline containing more than 10% Ethanol
are not the responsibility of the manufacturer and may
not be covered under warranty.
E-85 Usage In Non-Flex Fuel Vehicles
Non-FFV vehicles are compatible with gasoline contain-
ing 10% ethanol (E10). Gasoline with higher ethanol
content may void the vehicle’s warranty.
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If a Non-FFV vehicle is inadvertently fueled with E-85
fuel, the engine will have some or all of these symptoms:
•operate in a lean mode
•OBD II “Malfunction Indicator Light” on
•poor engine performance
•poor cold start and cold driveability
•increased risk for fuel system component corrosion
To fix a Non-FFV vehicle inadvertently fueled once with
E-85 perform the following:
•change the engine oil and oil filter
•disconnect and reconnect the battery
•drain the fuel tank (see your authorized dealer)
More extensive repairs will be required for prolonged
exposure to E-85 fuel.
MMT In Gasoline
MMT is a manganese-containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emissions system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
the gasoline contains MMT. It is even more important to
look for gasoline without MMT in Canada, because MMT
can be used at levels higher than those allowed in the
United States. MMT is prohibited in Federal and Califor-
nia reformulated gasoline.
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Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions and they would result in additional cost.
Therefore, you should not have to add anything to the
fuel.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine perfor-
mance and damage the emissions control system.(Continued)
CAUTION! (Continued)
•An out-of-tune engine or certain fuel or ignition
malfunctions can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune
or malfunctioning and may require immediate
service. Contact your authorized dealer for service
assistance.
•The use of fuel additives, which are now being
sold as octane enhancers, is not recommended.
Most of these products contain high concentra-
tions of methanol. Fuel system damage or vehicle
performance problems resulting from the use of
such fuels or additives is not the responsibility of
the manufacturer.
NOTE: Intentional tampering with the emissions con-
trol system can result in civil penalties being assessed
against you.
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