2008 JEEP WRANGLER TPMS

•Airbag deployment level (if applicable)
•Impact acceleration and angle
•Seat belt status
•Brake status (service and parking brakes)
•Accelerator status (including vehicle speed)
•Engine control status (including engine speed)
•Transmission gear selection
•Cruise control status
•Traction/stability control status
•Tire pressure monitoring system (TPMS) status
Child Restraint
Everyone in your vehicle needs to be buckled up at all
times — babies and children, too. Every state in the
United States and all Canadian provinces require that
small children ride in proper restraint systems. This is the
law, and you can be prosecuted for ignoring it.
Children 12 years and under should ride properly buck-
led up in a rear seat, if available. According to crash
statistics, children are safer when properly restrained in
the rear seats, rather than in the front.
There are different sizes and types of restraints for
children from newborn size to the child almost large
enough for an adult safety belt. Always check the child
seat owner’s manual to ensure you have the correct seat
for your child. Use the restraint that is correct for your
child.
62 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

21. Odometer/Trip Odometer Reset Button
Press this button to change the display from odometer to
either of two trip odometer settings. Trip A or Trip B will
appear when in the trip odometer mode. Press and hold
the button for two seconds to reset the trip odometer to 0
miles or kilometers. The odometer must be in trip mode
to reset.
22. Transmission Range Indicator
This display indicator shows the automatic transmission
gear selection.
23. Tire Pressure Monitoring Telltale LightEach 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 is significantly under-inflated. Accord-
ingly, 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 signifi-
cantly 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.
210 UNDERSTANDING YOUR INSTRUMENT PANEL

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
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.
24. Odometer/Trip Odometer
The odometer shows the total distance the vehicle has
been driven.
UNDERSTANDING YOUR INSTRUMENT PANEL 211
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▫Tire Identification Number (TIN) ..........316
▫ Tire Loading And Tire Pressure ...........317
 Tires — General Information ...............321
▫ Tire Pressure .........................321
▫ Tire Inflation Pressures .................322
▫ Tire Pressures For High-Speed Operation ....324
▫ Radial-Ply Tires ......................325
▫ Tire Spinning ........................325
▫ Tread Wear Indicators ..................326
▫ Life Of Tire .........................326
▫ Replacement Tires .....................327
▫ Alignment And Balance .................328
 Tire Chains ...........................329 
Tire Rotation Recommendations ............329
 Tire Pressure Monitor System (TPMS) ........330
▫ Base System .........................333
▫ General Information ...................335
 Fuel Requirements ......................336
▫ Reformulated Gasoline .................336
▫ Gasoline/Oxygenate Blends ..............337
▫ MMT In Gasoline .....................337
▫ Materials Added To Fuel ................338
▫ Fuel System Cautions ..................338
▫ Carbon Monoxide Warnings ..............339
 Adding Fuel ..........................340
▫ Fuel Filler Cap (Gas Cap) ...............340
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Follow the recommended tire rotation frequency for your
type of driving. Refer to the “Maintenance Schedule” in
Section 8 of this manual. More frequent rotation is
permissible if desired. The reasons for any rapid or
unusual wear should be corrected prior to rotation being
performed.
The suggested rotation method is the “forward-cross”
shown in the following diagram.TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold placard pressure.
The tire pressure will vary with temperature by about 1
psi (6.9 kPa) for every 12°F (6.5°C). This means that when
the outside temperature decreases, the tire pressure will
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
three hours, or driven less than 1 mi (1 km) after a three
hour period.Refer to the “Tires — General Informa-
tion” 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.
330 STARTING AND OPERATING

The TPMS 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 temperature
effects, or natural pressure loss through the tire.
The TPMS 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 recommended
cold placard pressure. Once the Tire Pressure Monitoring
Telltale Light has been illuminated, the tire pressure must
be increased to the recommended cold placard 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 extin-
guish once the updated tire pressures have been received.
The vehicle may need to be driven for up to 10 minutes
above 15 mph (25 km/h) to receive this information.For example, your vehicle may have a recommended
cold (parked for more than three hours) air pressure of 35
psi (241 kPa). If the ambient temperature is 68°F (20°C)
and the measured tire pressure is 30 psi (207 kPa), a
temperature drop to 20°F (-7°C) will decrease the tire
pressure to approximately 26 psi (179 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 30
psi (207 kPa), but the Tire Pressure Monitoring Telltale
Light will still 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 placard pressure value.
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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.
Aftermarket 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.
CAUTION!
After inspecting or adjusting the tire pressure always
reinstall the valve stem cap. This will prevent mois-
ture 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.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
332 STARTING AND OPERATING

•The TPMS is not a substitute for proper tire mainte-
nance, 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 Tire
Pressure Monitoring Telltale Light.
•Seasonal temperature changes will affect tire pressure,
and the TPM System will monitor the actual tire
pressure in the tire.
Base 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:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in the spare
wheel if the vehicle is equipped with a matching full size
spare wheel and tire assembly. The matching full size
spare tire can be used in place of any of the four road
tires. A low spare tire will not cause the Tire Pressure
Monitoring Telltale Light to illuminate or the chime to
sound. 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. Should this
occur, you should stop as soon as possible, check the
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