2008 JEEP GRAND CHEROKEE warning

NOTE:Your system can be set to display pressure units
in PSI, kPa, or BAR.
If the ignition key is cycled, this sequence will repeat,
providing the system fault still exists. If the system fault
no longer exists, the ªTire Pressure Monitoring Telltale
Lightº will no longer flash, the9CHECK TPM SYSTEM9text message will not be present, and a pressure value
will be displayed instead of dashes. A system fault can
occur by any of the following scenarios:
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.
In addition, the ªTire Pressure Monitoring Telltale Lightº
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
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²An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your dealer for service assistance.
²The use of fuel additives, which are now being sold as
octane enhancers, is not recommended. Most of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
²Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas, which can kill.
Never run the engine in a closed area, such as a
garage, and never sit in a parked vehicle with the
engine running for an extended period. If the vehicle is
stopped in an open area with the engine running for
more than a short period, adjust the ventilation system
to force fresh, outside air into the vehicle.
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CAUTION!
Damage to the fuel system or emission control sys-
tem could result from using an improper fuel cap
(gas cap). A poorly fitting cap could let impurities
into the fuel system. Also, a poorly fitting after-
market cap can cause the MIL (Malfunction Indicator
Light) to illuminate, due to fuel vapors escaping from
the system.
CAUTION!
A poorly fitting gas cap may cause the Malfunction
Indicator Light to turn on.
CAUTION!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
NOTE:When the fuel nozzle ªclicksº or shuts off, the
fuel tank is full.
WARNING!
²Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank filled.
²Never add fuel when the engine is running. This is
in violation of most state and federal fire regula-
tions and will cause the malfunction indicator
light to turn on.
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NOTE:Tighten the gas cap about 1/4 turn until you
hear one click. This is an indication that cap is properly
tightened.
If the gas cap is not tighten properly, the Malfunction
Indicator Light will come on. Be sure the gas cap is
tightened every time the vehicle is refueled.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
ªCHECK GASCAPº message will be displayed in the
EVIC (Electronic Vehicle Information Center). Refer to
ªElectronic Vehicle Information Centerº in Section 4 of
this manual. Tighten the fuel filler cap until a ªclickingº
sound is heard. This is an indication that the fuel filler
cap is properly tightened. Refer to ªOnboard Diagnostic
System Ð OBDIIº in Section 7 of this manual for more
information.
CAUTION!
Damage to the fuel system or emission control sys-
tem could result from using an improper fuel tank
filler cap (gas cap). A poorly fitting cap could let
impurities into the fuel system.
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WARNING!
²Never add fuel when the engine is running.
²Never have any smoking materials lit in or near
the vehicle when the fuel cap is removed or the
tank filled.
TRAILER TOWING
In this section you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer carefully re-
view this information to tow your load as efficiently and
safely as possible.
To maintain warranty coverage, follow the requirements
and recommendations in this manual concerning ve-
hicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
exceed the GVWR.
Gross Trailer Weight (GTW)
The gross trailer weight (GTW) is the weight of the trailer
plus the weight of all cargo, consumables and equipment
(permanent or temporary) loaded in or on the trailer in its
9loaded and ready for operation9condition. The recom-
mended way to measure GTW is to put your fully loaded
trailer on a vehicle scale. The entire weight of the trailer
must be supported by the scale.
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Gross Combination Weight Rating (GCWR)
The gross combination weight rating (GCWR) is the total
permissible weight of your vehicle and trailer when
weighed in combination. (Note that GCWR ratings in-
clude a 150 lbs (68 kg) allowance for the presence of a
driver).
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front and rear
axles. Distribute the load over the front and rear axles
evenly. Make sure that you do not exceed either front or
rear GAWR.
WARNING!
It is important that you do not exceed the maximum
front or rear GAWR. A dangerous driving condition
can result if either rating is exceeded. You could lose
control of the vehicle and have an accident.
Tongue Weight (TW)
The downward force exerted on the hitch ball by the
trailer. In most cases it should not be less than 10% or
more than 15% of the trailer load. You must consider this
as part of the load on your vehicle.
Frontal Area
The maximum height and maximum width of the front of
a trailer.
Trailer Sway Control
The trailer sway control is a telescoping link that can be
installed between the hitch receiver and the trailer tongue
that typically provides adjustable friction associated with
the telescoping motion to dampen any unwanted trailer
swaying motions while traveling.
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Weight-Carrying Hitch
A weight-carrying hitch supports the trailer tongue
weight, just as if it were luggage located at a hitch ball or
some other connecting point of the vehicle. These kind of
hitches are the most popular on the market today and
they're commonly used to tow small- and medium-sized
trailers.
Weight-Distributing Hitch
A weight-distributing system works by applying lever-
age through spring (load) bars. They are typically used
for heavier loads, to distribute trailer tongue weight to
the tow vehicle's front axle and the trailer axle(s). When
used in accordance with the manufacturers' directions, it
provides for a more level ride, offering more consistent
steering and brake control thereby enhancing towing
safety. The addition of a friction/hydraulic sway control
also dampens sway caused by traffic and crosswinds and
contributes positively to tow vehicle and trailer stability.
Trailer sway control and a weight distributing (loadequalizing) hitch are recommended for heavier Tongue
Weights (TW) and may be required depending on Vehicle
and Trailer configuration/loading to comply with gross
axle weight rating (GAWR) requirements.
WARNING!
An improperly adjusted Weight Distributing Hitch
system may reduce handling, stability, braking per-
formance, and could result in an accident.
Weight Distributing Systems may not be compatible
with Surge Brake Couplers. Consult with your hitch
and trailer manufacturer or a reputable Recreational
Vehicle dealer for additional information.
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CAUTION!
²Avoid towing a trailer for the first 500 miles (805
km) of vehicle operation. Doing so may damage
your vehicle.
²During the first 500 miles (805 km) of trailer
towing, limit your speed to 50 mph (80 km/h).
Perform the maintenance listed in Section 8 of this
manual. When towing a trailer, never exceed the GAWR,
or GCWR, ratings.
WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have an accident.
²When hauling cargo or towing a trailer, do not over-
load your vehicle or trailer. Overloading can cause a
loss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, chas-
sis structure or tires.
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