2012 JEEP GRAND CHEROKEE fuel pressure

Periodic Safety Checks You Should
Make Outside The Vehicle
Tires
Examine tires for excessive tread wear and
uneven wear patterns. Check for stones, nails,
glass, or other objects lodged in the tread or
sidewall. Inspect the tread for cuts and cracks.
Inspect sidewalls for cuts, cracks and bulges.
Check the wheel nuts for tightness. Check the
tires (including spare) for proper cold inflation
pressure.Lights
Have someone observe the operation of exte-
rior lights while you work the controls. Check
turn signal and high beam indicator lights on
the instrument panel.
Door Latches
Check for positive closing, latching, and lock-
ing.
Fluid Leaks
Check area under vehicle after overnight park-
ing for fuel, engine coolant, oil, or other fluid
leaks. Also, if gasoline fumes are detected or if
fuel, power steering fluid, or brake fluid leaks
are suspected, the cause should be located
and corrected immediately.
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As an added safety feature, your vehicle has
been equipped with a Tire Pressure Monitoring
System (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires is
significantly under-inflated. Accordingly, when
the low tire pressure telltale illuminates, you
should stop and check your tires as soon as
possible, and inflate them to the proper pres-
sure. 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.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure,
even if under-inflation has not reached the level
to trigger illumination of the TPMS low tire
pressure telltale.Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The TPMS
malfunction indicator is combined with the low
tire pressure telltale. When the system detects
a malfunction, the telltale will flash for approxi-
mately one minute and then remain continu-
ously illuminated. This sequence will continue
upon subsequent vehicle start-ups as long as
the malfunction exists. When the malfunction
indicator is illuminated, the system may not be
able to detect or signal low tire pressure as
intended. TPMS malfunctions may occur for a
variety of reasons, including the installation of
replacement or alternate tires or wheels on the
vehicle that prevent the TPMS from functioning
properly. Always check the TPMS malfunction
telltale after replacing one or more tires or
wheels on your vehicle, to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures
and warning have been established for the tire
size equipped on your vehicle. Undesirable
system operation or sensor damage may re-
sult when using replacement equipment that
is not of the same size, type, and/or style.
Aftermarket wheels can cause sensor dam-
age. 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.
12. Park/Headlight ON Indicator — If
Equipped This indicator will illuminate when
the park lights or headlights are
turned on.
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•TIRES — GENERAL INFORMATION ............... 252
• Tire Pressure .......................... 252
• Tire Inflation Pressures .................... 253
• High Speed Operation ..................... 253
• Radial-Ply Tires ......................... 253
• Limited-Use Spare – If Equipped ............... 253
• Tire Spinning .......................... 253
• Tire Chains ............................ 254
• Treadwear Indicators ...................... 254
• Life Of Tire ............................ 255
• Replacement Tires ....................... 255
• Directional Tread Pattern Tires – If Equipped ........ 256
• TIRE ROTATION RECOMMENDATIONS ............. 256
• Non-Directional Tires Only .................. 256
• TIRE PRESSURE MONITOR SYSTEM (TPMS) .......... 257
• Base System ........................... 258
• Premium System – If Equipped ................ 259
• TPMS Deactivation ....................... 261
• General Information ...................... 262
• FUEL REQUIREMENTS — GASOLINE ENGINE ......... 262
• 3.6L Engine ........................... 262
• 5.7L Engine ........................... 262
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LOCK position, wait 10 to 15 seconds, then
repeat the “Normal Starting” procedure.
CAUTION!
To prevent damage to the starter, wait 10 to
15 seconds before trying again.
After StartingThe idle speed is controlled automatically and it
will decrease as the engine warms up.
Normal Starting – Diesel EngineObserve the following when the engine is op-
erating.
•All message center lights are off.
• Malfunction Indicator Light (MIL) is off.
• Low Oil Pressure Light is off.
Cold Weather Precautions
Operation in ambient temperature below 32°F
(0°C) may require special considerations. The
following chart suggests these options. *No. 1 Ultra Low Sulfur Diesel Fuel (ULSD)
should only be used where extended arctic
conditions (-10°F/-23°C) exist.
NOTE:
•
Use of Climatized ULSD Diesel Fuel or
Number 1 ULSD Diesel Fuel results in a
noticeable decrease in fuel economy.
• Climatized ULSD Diesel Fuel is a blend of
Number 2 ULSD and Number 1 ULSD
Diesel Fuels, which reduces the tempera-
ture at which wax crystals form in fuel.
NOTE:
This engine requires the use of “Ultra Low
Sulfur Diesel Fuel.” Use of incorrect fuel
could result in exhaust system damage. Re- fer to “Fuel Requirements – Diesel Engine”
in “Starting and Operating” for further infor-
mation.
Battery Blanket Usage
A battery loses 60% of its cranking power as
the battery temperature decreases to 0°F
(-18°C). For the same decrease in temperature,
the engine requires twice as much power to
crank at the same RPM. The use of battery
blankets will greatly increase starting capability
at low temperatures. Suitable battery blankets
are available from your authorized MOPAR
dealer.
Engine Starting Procedure
WARNING!
Never pour fuel or other flammable liquid into
the air inlet opening in an attempt to start the
vehicle. This could result in a flash fire causing
serious personal injury.
1. The shift lever must be in the NEUTRAL or
PARK position before you can start the engine.
2. With your foot on the brake pedal, press the
ENGINE START/STOP button.
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3. Watch the “Wait To Start Light” in the instru-
ment cluster. Refer to “Instrument Cluster” in
“Understanding Your Instrument Panel” for fur-
ther information. It may glow for up to three
seconds, depending on engine temperature.
4. When the “Wait To Start Light” goes out, the
engine will automatically start.
5. After the engine starts, allow it to idle for
approximately 30 seconds before driving. This
allows oil to circulate and lubricate the turbo-
charger.
Avoid prolonged idling in ambient tempera-
tures below 0°F (-18°C). Long periods of idling
may be harmful to your engine because com-
bustion chamber temperatures can drop so low
that the fuel may not burn completely. Incom-
plete combustion allows carbon and varnish to
form on piston rings and injector nozzles. Also,
the unburned fuel can enter the crankcase,
diluting the oil and causing rapid wear to the
engine.Engine Warm Up
Avoid full throttle operation when the engine is
cold. When starting a cold engine, bring the
engine up to operating speed slowly to allow
the oil pressure to stabilize as the engine
warms up.
NOTE:
High-speed, no-load running of a cold en-
gine can result in excessive white smoke
and poor engine performance. No-load en-
gine speeds should be kept under 1,200
RPM during the warm-up period, especially
in cold ambient temperature conditions.
If temperatures are below 32°F (0°C), operate
the engine at moderate speeds for five minutes
before full loads are applied.
Engine Idling – In Cold Weather
Avoid prolonged idling in ambient tempera-
tures below 0°F (-18°C). Long periods of idling
may be harmful to your engine because com-
bustion chamber temperatures can drop so low
that the fuel may not burn completely. Incom-
plete combustion allows carbon and varnish to
form on piston rings and injector nozzles. Also,the unburned fuel can enter the crankcase,
diluting the oil and causing rapid wear to the
engine.
Stopping The Engine
Before turning off your turbo diesel engine,
always allow the engine to return to normal idle
speed and run for several seconds. This as-
sures proper lubrication of the turbocharger.
This is particularly necessary after any period
of hard driving.
Idle the engine a few minutes before routine
shutdown. After full load operation, idle the
engine three to five minutes before shutting it
down. This idle period will allow the lubricating
oil and coolant to carry excess heat away from
the combustion chamber, bearings, internal
components, and turbocharger. This is espe-
cially important for turbocharged, charge air
cooled engines.
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•Each time the ignition is turned ON, the
ESC system will be ON even if it was
turned off previously.
• The ESC system will make buzzing or
clicking sounds when it is active. This is
normal; the sounds will stop when ESC
becomes inactive following the maneuver
that caused the ESC activation.
The “ESC OFF Indicator Light” in-
dicates the Electronic Stability
Control (ESC) is off.
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the
safe and satisfactory operation of your vehicle.
Three primary areas are affected by improper
tire pressure: Safety
WARNING!
•
Improperly inflated tires are dangerous and
can cause accidents.
• Under-inflation increases tire flexing and
can result in tire failure.
• Over-inflation reduces a tire’s ability to
cushion shock. Objects on the road and
chuck holes can cause damage that results
in tire failure.
• Unequal tire pressures can cause steering
problems. You could lose control of your
vehicle.
• Over-inflated or under-inflated tires can af-
fect vehicle handling and can fail suddenly,
resulting in loss of vehicle control.
Always drive with each tire inflated to the
recommended pressure. Economy
Improper inflation pressures can cause uneven
wear patterns to develop across the tire tread.
These abnormal wear patterns will reduce
tread life resulting in a need for earlier tire
replacement. Under-inflation also increases tire
rolling resistance and results in higher fuel
consumption.
Ride Comfort and Vehicle Stability
Proper tire inflation contributes to a comfortable
ride. Over-inflation produces a jarring and un-
comfortable ride. Both under-inflation and over-
inflation affect the stability of the vehicle and
can produce a feeling of sluggish response or
over responsiveness in the steering.
Unequal tire pressures can cause erratic and
unpredictable steering response.
Unequal tire pressure from side to side may
cause the vehicle to drift left or right.
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CAUTION!(Continued)
• After inspecting or adjusting the tire pres-
sure always reinstall the valve stem cap.
This will prevent moisture and dirt from
entering the valve stem, which could dam-
age the Tire Pressure Monitoring Sensor.
NOTE:
• The TPMS is not intended to replace nor-
mal tire care and maintenance, or to pro-
vide 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 maintenance, 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 the display of the “TPM
Telltale Light” and the “TIRE LOW PRES-
SURE” message.
• Seasonal temperature changes will affect
tire pressure, and the TPMS will monitor
the actual tire pressure in the tire.
Base SystemThe Tire Pressure Monitor System (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 regu-
larly check the tire pressure in all of your
tires, and to maintain the proper pressure.
The TPMS consists of the following compo-
nents:
•Receiver Module
• Four Tire Pressure Monitoring Sensors
• Tire Pressure Monitoring Telltale Light A low spare tire will not cause the “Tire Pressure
Monitoring Telltale Light” to illuminate, a warn-
ing message to appear, or the chime to sound.
The “Tire Pressure Monitoring Telltale
Light” will illuminate in the instrument
cluster, a “TIRE LOW PRESSURE”
message will display in the instrument
cluster for 5 seconds, 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 Monitoring Telltale Light” will
extinguish, once the updated 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.
The “Tire Pressure Monitoring Telltale Light” will
flash on and off for 75 seconds, and remain on
solid when a system fault is detected. In addi-
tion, a “SERVICE TPM SYSTEM” message may
be displayed for approximately 5 seconds
when a system fault is detected, and a chime
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Telltale Lightwill flash on and off for 75 sec-
onds and then turn off, and the Electronic
Vehicle Information Center (EVIC) will display
the “SERVICE TPM SYSTEM” message. The
EVIC will also display pressure values in place
of the dashes. On the next ignition switch cycle
the SERVICE TPM SYSTEM message will no
longer be displayed as long as no system fault
exists.
General InformationTransmitter and receivers operate on a carrier
frequency of 433.92 MHz as required by EEC
regulations. These devices must be certified to
conform to specific regulations in each indi-
vidual country. Two sets of regulations are
involved: ETS (European Telecommunication
Standard) 300–220, which most countries use,
and German BZT federal regulation 225Z125,
which is based on ETC 300–220 but has addi-
tional unique requirements. Other defined re-
quirements are noted in ANNEX VI of COMMIS-
SION DIRECTIVE 95/56/EC. Operation is
subject to the following conditions:
• This device may not cause harmful interfer-
ence. •
This device must accept any interference
received, including interference that may
cause undesired operation.
FUEL REQUIREMENTS —
GASOLINE ENGINE
3.6L Engine
These engines are designed to meet all emis-
sions regulations and provide excellent fuel
economy and performance when using high-
quality unleaded gasoline with a minimum re-
search octane rating of 91. The use of premium
gasoline is not recommended, as it will not
provide any benefit over regular gasoline in
these engines.
5.7L EngineTheses engines are designed to meet all emis-
sions regulations and provide satisfactory fuel
economy and performance when using high-
quality unleaded gasoline having an octane
range of 91 to 95. The manufacturer recom-
mends the use of 95 octane for optimum per-
formance. 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
experience 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 Worldwide Fuel Charter,
WWFC) which define fuel properties necessary
to deliver enhanced emissions, performance,
and durability for your vehicle. The manufac-
turer recommends the use of gasoline that
meets the WWFC specifications if they are
available.
Besides using unleaded gasoline with the
proper octane rating, gasolines that contain
detergents, corrosion and stability additives
are recommended. Using gasolines that have
these additives may help improve fuel
economy, reduce emissions, and maintain ve-
hicle performance.
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