2008 JEEP GRAND CHEROKEE TPMS

12. Tire Pressure Monitoring Telltale Light
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommended
by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. (If your vehicle
has tires of a different size than the size indicated on the
vehicle placard or tire inflation pressure label, you should
determine the proper tire inflation pressure for those
tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one or
more of your tires are significantly under-inflated. Ac-
cordingly, when the low tire pressure telltale illuminates,
you should stop and check your tires as soon as possible,
and inflate them to the proper pressure. Driving on a
significantly under-inflated tire causes the tire to over-
heat and can lead to tire failure. Under-inflation alsoreduces 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
approximately one minute and then remain continuously
illuminated. This sequence will continue upon subse-
quent vehicle start-ups as long as the malfunction exists.
When the malfunction indicator is illuminated, the sys-
tem may not be able to detect or signal low tire pressure
as intended. TPMS malfunctions may occur for a variety
UNDERSTANDING YOUR INSTRUMENT PANEL 177
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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 replace-
ment 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 opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. After-market 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.
13. Temperature Gauge
The temperature gauge shows engine coolant tempera-
ture. Any reading within the normal range indicates that
the engine cooling system is operating satisfactorily.
178 UNDERSTANDING YOUR INSTRUMENT PANEL

mTire Safety Information...................259
NTire Markings........................259
NTire Identification Number (TIN)..........262
NTire Loading And Tire Pressure...........263
mTires Ð General Information...............267
NRun Flat Tires........................267
NTire Pressure.........................267
NTire Inflation Pressures.................269
NTire Pressures For High Speed Operation....270
NRadial-Ply Tires......................271
NTire Spinning........................271
NTread Wear Indicators..................272
NLife Of Tire.........................272NReplacement Tires.....................273
NAlignment And Balance.................274
mTire Rotation Recommendations............275
mTire Pressure Monitor System (TPMS)........275
NPremium System......................275
NGeneral Information...................278
mFuel Requirements......................278
N6.1L Engine.........................278
NReformulated Gasoline.................279
NGasoline/Oxygenate Blends..............279
NMMT In Gasoline.....................280
NMaterials Added To Fuel................280
NFuel System Cautions..................280
240 STARTING AND OPERATING

Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
TIRE ROTATION RECOMMENDATIONS
Do not rotate the tires as the wider rear tires will not fit
on the front of the vehicle.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
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 check the
tire pressure in all of your tires regularly and to maintain
the proper pressure.The Tire Pressure Monitor System (TPMS) consists of the
following components:
²Receiver Module
²4 Tire Pressure Monitoring Sensors
²3 Trigger Modules (mounted in three of the four wheel
wells)
²Various Tire Pressure Monitoring System Messages,
which display in the Electronic Vehicle Information
Center (EVIC), and a graphic displaying tire pressures
²Tire Pressure Monitoring Telltale Light
Tire Pressure Monitoring Low Pressure Warnings
The ªTire Pressure Monitoring Telltale Lightº 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
Electronic Vehicle Information Center (EVIC) will display
STARTING AND OPERATING 275
5

any of the four active road tires. The vehicle may need to
be driven for up to 10 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:
²This device may not cause harmful interference.
²This device must accept any interference received,
including interference that may cause undesired op-
eration.
The tire pressure sensors are covered under one of the
following licenses:
United States.....................KR5S120123
Canada........................2671-S120123
FUEL REQUIREMENTS
6.1L Engine
The 6.1L 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.
278 STARTING AND OPERATING

Cargo .............................. 162
Center Mounted Stop................... 351
Cruise.............................. 180
Daytime Running...................... 123
Dimmer Switch, Headlight............. 119,124
Electronic Stability Program (ESP)
Indicator.......................141,176,180
Electronic Throttle Control Warning......... 181
Fog ..........................123,181,350
Fuses............................... 338
Hazard Warning Flasher................. 298
Headlight Switch...................... 120
Headlights........................... 347
Headlights On With Wipers............... 121
High Beam Indicator.................... 174
Illuminated Entry....................... 19
Instrument Cluster..................120,122
Interior..........................122,125
Lights On Reminder.................... 123Low Fuel............................ 181
LowTire ............................ 177
Malfunction Indicator (Check Engine)........ 174
Map Reading......................... 125
Oil Pressure.......................... 176
Passing............................. 124
Reading..........................125,148
Rear Servicing........................ 350
Rear Tail............................ 350
Seat Belt Reminder..................... 180
Security Alarm (Theft Alarm).............. 176
Service.............................. 347
Service Engine Soon (Malfunction Indicator) . . . 174
Side Marker.......................... 350
SmartBeams.......................... 121
Tire Pressure Monitoring (TPMS)........... 177
Traction Control....................141,176
Turn Signal.................. 119,124,349,350
Vanity Mirror.......................... 77
394 INDEX

Tire Markings.......................... 259
Tire Safety Information.................... 259
Tires ............................68,267,382
Air Pressure.......................... 269
Alignment and Balance.................. 274
General Information.................... 267
High Speed.......................... 270
Inflation Pressures..................... 269
Life of Tires.......................... 272
Load Capacity.....................263,264
Pressure Monitor System (TPMS)........... 275
Pressure Warning Light.................. 177
Quality Grading....................... 382
Radial.............................. 271
Replacement......................... 273
Rotation............................. 275
Safety............................68,259
Sizes............................... 260
Spinning............................ 271Tread Wear Indicators................... 272
Tongue Weight/Trailer Weight.............. 290
Towing............................... 285
Behind a Motor Home.................. 296
Guide.............................. 290
Recreational.......................... 296
Weight.............................. 290
Towing Vehicle Behind a Motor Home......... 296
Traction Control......................... 135
Traction Control Light.................... 176
Trailer Sway Control (TSC)................. 140
Trailer Towing.......................... 285
Cooling System Tips.................... 296
Hitches............................. 289
Minimum Requirements................. 291
Trailer and Tongue Weight................ 290
Trailer Towing Guide..................... 290
Trailer Weight.......................... 290
Transmission........................... 333
INDEX 401
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