2012 JEEP GRAND CHEROKEE flat tire

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.
430 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 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
5
STARTING AND OPERATING 431

“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

Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options, trailer
tongue weight, and cargo. The label also specifies maxi-
mum capacities of front and rear axle systems (GAWR).
Total load must be limited, so GVWR, and front and rear
GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck or any given vehicle can carry, including
the weight of the driver, all passengers, options and
cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle’s GAWR is determined by the components in
the system with the lowest load carrying capacity (axle,springs, tires, or wheels). Heavier axles or suspension
components, sometimes specified by purchasers for in-
creased durability, does not necessarily increase the ve-
hicle’s GVWR.
Tire Size
The tire size on the label represents the actual tire size on
your vehicle. Replacement tires must be equal to the load
capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
444 STARTING AND OPERATING

Towing Requirements – Tires

Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
Check the trailer tires for proper tire inflation pres-
sures before trailer usage.
Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires – General
Information” in “Starting and Operating” for proper
inspection procedure.
When replacing tires, refer to “Tires – General Infor-
mation” in “Starting and Operating” for proper tire
replacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
Towing Requirements – Trailer Brakes

Donotinterconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
An electronically actuated trailer brake controller is
required when towing a trailer with electronically
actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers over
1,000 lbs (454 kg) and required for trailers in excess of
2,000 lbs (907 kg).
454 STARTING AND OPERATING

WHAT TO DO IN EMERGENCIES
CONTENTS
Hazard Warning Flashers................ 460
If Your Engine Overheats................ 460
Jacking And Tire Changing............... 461
▫RunFlatTires ....................... 461
Jump-Starting........................ 462▫Preparations For Jump-Start............. 462
▫Jump-Starting Procedure............... 464
Emergency Tow Hooks — If Equipped...... 466
Shift Lever Override................... 467
Towing A Disabled Vehicle............... 468
6

to high. This allows the heater core to act as a
supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads HOT
(H), pull over and stop the vehicle. Idle the vehicle
with the air conditioner turned off until the pointer
drops back into the normal range. If the pointer
remains on HOT (H), and you hear continuous
chimes, turn the engine off immediately and call for
service.
WARNING!
You or others can be badly burned by hot engine
coolant (antifreeze) or steam from your radiator. If
you see or hear steam coming from under the hood,
do not open the hood until the radiator has had time
to cool. Never try to open a cooling system pressure
cap when the radiator or coolant bottle is hot.
JACKING AND TIRE CHANGING
Run Flat Tires
This vehicle is equipped with run flat tires. Although the
tires are designed with a “run flat” feature that allows the
vehicle to be driven approximately 50 miles (80 km) at
55 mph (88 km/h). immediate service should be ob-
tained.6
WHAT TO DO IN EMERGENCIES 461

WARNING!
Do not exceed 50 mph (80 km/h) if the “Tire Pressure
Monitoring Telltale Light” is illuminated. Vehicle
handling and braking may be reduced. You could
have a collision and be severely or fatally injured.
NOTE:The “run flat” feature eliminates the need for a
spare tire and jack. This vehicle is not equipped with
either a spare tire or jack.
JUMP-STARTING
If your vehicle has a discharged battery it can be jump-
started using a set of jumper cables and a battery in
another vehicle or by using a portable battery booster
pack. Jump-starting can be dangerous if done improperly
so please follow the procedures in this section carefully.NOTE:When using a portable battery booster pack
follow the manufacturer’s operating instructions and
precautions.
CAUTION!
Do not use a portable battery booster pack or any
other booster source with a system voltage greater
than 12 Volts or damage to the battery, starter motor,
alternator or electrical system may occur.
WARNING!
Do not attempt jump-starting if the battery is frozen.
It could rupture or explode and cause personal injury.
Preparations For Jump-Start
The battery in your vehicle is located under the passen-
ger’s front seat. There are remote locations located under
the hood to assist in jump-starting.
462 WHAT TO DO IN EMERGENCIES