2012 JEEP GRAND CHEROKEE sensor

counteracting the oversteer or understeer condition. En-
gine power may also be reduced to help the vehicle
maintain the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESC applies the brake of the appro-
priate wheel to assist in counteracting the oversteer or
understeer condition.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
•Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” lo-
cated in the instrument cluster will start to flash as soon
as the tires lose traction and the ESC system becomes
active. The “ESC Activation/Malfunction IndicatorLight” also flashes when the TCS is active. If the “ESC
Activation/Malfunction Indicator Light” begins to flash
during acceleration, ease up on the accelerator and apply
as little throttle as possible. Be sure to adapt your speed
and driving to the prevailing road conditions.
WARNING!
The Electronic Stability Control (ESC) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions. ESC cannot prevent col-
lisions, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. The capabilities of an ESC equipped
vehicle must never be exploited in a reckless or
dangerous manner which could jeopardize the user ’s
safety or the safety of others.
The ESC system has three available operating modes.
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across an axle quite similarly to a limited slip differential.
If one wheel on an axle is spinning faster than the other,
the system will apply the brake of the spinning wheel
and allow more engine torque to be applied to the wheel
that is not spinning. To improve the vehicle’s traction
when driving with tire chains, or when starting off in
deep snow, sand, or gravel, it may be desirable to switch
to the “Partial Off” mode by momentarily pressing the
“ESC Off” switch.
WARNING!
With the ESC switched OFF, the enhanced vehicle
stability offered by ESC is unavailable. In an emer-
gency evasive maneuver, the ESC system will not
engage to assist in maintaining stability. The “Full
Off” ESC mode is intended for off-highway or off-
road only.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an exces-
sively swaying trailer and will take the appropriate
actions to attempt to stop the sway. The system may
reduce engine power and apply the brake of the appro-
priate wheel(s) to counteract the sway of the trailer. TSC
will become active automatically once an excessively
swaying trailer is recognized. No driver action is re-
quired. Note that TSC cannot stop all trailers from
swaying. Always use caution when towing a trailer and
follow the trailer tongue weight recommendations. Refer
to “Trailer Towing” in “Starting and Operating” for
further information. When TSC is functioning, the “ESC
Activation/Malfunction Indicator Light” will flash, the
engine power may be reduced and you may feel the
brakes being applied to individual wheels to attempt to
stop the trailer from swaying. TSC is disabled when the
ESC system is in the “Partial Off” mode.
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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
equipment that is not of the same size, type, and/or
style. Aftermarket wheels can cause sensor dam-
age. Do not use aftermarket tire sealants or balance
beads if your vehicle is equipped with a TPMS, as
damage to the sensors may result.
(Continued)
CAUTION! (Continued)
•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.
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•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.
•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Premium System
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim-mounted electronic sensors to
monitor tire pressure levels. 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 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 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 one or more Low Pressure messages
(Left Front, Left Rear, Right Front, Right Rear) for a
minimum of five seconds, and a graphic display of the
pressure value(s) with the low tire(s) “flashing.” Refer to
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“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.
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.
432 STARTING AND OPERATING

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, theSERVICE TPM SYSTEMmessage 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 the trigger compo-
nent an incorrect sensor location fault. In this case, the
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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 theSERVICE 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 SYSTEMmes-
sage 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 sec-
onds and then remain on solid, and the EVIC will display
aSERVICE TPM SYSTEMmessage 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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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
FUEL REQUIREMENTS
6.4L Engine
The 6.4L engine is designed to meet all
emissions regulations and provide excel-
lent fuel economy and performance when
using high-quality premium unleaded
gasoline with an octane rating of 91 or
higher.
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
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