2004 JEEP GRAND CHEROKEE light

MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not his/her gasoline contains MMT.
It is even more important to look for gasoline without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasoline.
Sulfur In Gasoline
If you live in the northeast United States, your vehicle
may have been designed to meet California low emission
standards with clean burning, low sulfur, California
gasoline. Gasoline sold outside of California is permitted
to have higher sulfur levels which may affect the perfor-
mance of the vehicle's catalytic converter. This may cause
the ªMalfunction Indicator Lightº to illuminate.
Illumination of this light while operating on high sulfur
gasoline does not necessarily mean your emission control
system is malfunctioning. The manufacturer recom-
mends that you try a different brand of unleaded gaso-
line having lower sulfur to determine if the problem is
fuel related prior to returning your vehicle to an autho-
rized dealer for service.
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CAUTION!
If the ªMalfunction Indicator Lightº is flashing,
immediate service is required. See ªOnboard Diag-
nostic Systemº in Section 7 of this manual.
Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions.
FUEL TANK FILLER CAP (GAS CAP)
WARNING!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
The gas cap is located behind the fuel filler door, on the
left side of the vehicle. If the gas cap is lost or damaged,
be sure the replacement cap has been designed for use
with this vehicle. When the gas cap is removed for
refueling, it can be placed in the fuel filler door while
filling the fuel tank.
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TRAILER TOWING
In this section you will find information on limits to the
type of towing you can reasonably do with your vehicle.
And you will find safety tips. Before towing a trailer
carefully review this information to tow your load as
efficiently and safely as possible.
The factory-installed Class III and Class IV Trailer Tow
Packages include a frame mounted receptacle and the
above required equipment. They also include some nec-
essary provisions for connecting an aftermarket electric
brake controller. It is a light blue wire, identified with a
tag, located under the instrument panel behind the brake
pedal. Other equipment, such as trailer sway controls
and braking equipment, trailer equalizing (leveling)
equipment and low profile mirrors, may also be required
or strongly recommended.To maintain warranty coverage, follow the requirements
and recommendations in this manual concerning ve-
hicles used for trailer towing.
Perform maintenance services as prescribed in the appro-
priate ªMaintenance Schedule.º Refer to Section 8 of this
manual. When your vehicle is used for trailer towing,
never exceed the gross axle weight rating (GAWR) by the
addition of:
²The tongue weight of the trailer.
²The weight of any other type of cargo or equipment
put in or on your vehicle.
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WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
²Be sure a trailer is loaded heavier in front, about 10%
to 15% of gross trailer weight. Loads balanced over the
wheels or heavier in the rear cause the trailer to sway
severelyside to side which will cause loss of control of
the vehicle and trailer. Failure to load trailers heavier
in front is the cause of many trailer related accidents.
²Donotinterconnect the hydraulic brake system of
your vehicle with that of the trailer. This could cause
inadequate braking and possible personal injury.
²Trailer brakes are required for trailers in excess of
2,000 lbs (907 kg).
²Donotconnect a trailer lighting system directly to the
lighting system of your vehicle. Use an approved
trailer wiring harness. Failure to do so could damage
the vehicle electrical system and/or result in personal
injury.
²When hauling cargo or towing a trailer,do notover-
load your vehicle or trailer. Overloading can cause a
loss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, body
structure or tires.
²Make certain that the load is secured in the trailer and
will not shift during travel.
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²It is recommended thatanyhitches installed on your
vehicle be factory installed, or installed by a dealer
using factory approved parts. Factory approved parts
are specifically engineered with your vehicle's perfor-
mance in mind, including the possibility that it will be
involved in an accident. Other hitches may not have
been so engineered. Vehicle performance, including
vehicle damage in an accident situation, may therefore
be different.
²If trailer towing is required and your vehicle is not
equipped with a trailer tow package, the Mopart
accessory towing harnesses are the only approved
method to provide for trailer lights. These harnesses
are designed to provide current to the trailer lights but
bypass the module designed to monitor tail lights.
Refer to the package instructions for details.
Trailer and Tongue Weight
Gross Trailer Weight (GTW) means the weight of the
trailer plus the weight of all cargo, consumables and
equipment loaded on the trailer when in actual underway
towing condition. The best 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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NOTE:If you tow a trailer frequently, especially in hilly
country or when the outdoor temperature is high, we
recommend that you change the transmission fluid at
30,000 mile (48 000 km) intervals.
CAUTION!
When pulling a heavy load or driving a fully loaded
vehicle use a premium unleaded fuel to help prevent
spark knock. If spark knock persists, lighten the
load. Otherwise, engine piston damage may result.
Other restrictions apply concerning trailer type, trailer
frontal area and tongue weight. Carefully review the
ªMinimum Vehicle Requirementsº chart in this section
before towing a trailer.
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.)
CAUTION!
Internal damage to the transfer case will occur if a
front or rear wheel lift is used when recreational
towing.
NOTE:The transfer case must be in the N (Neutral)
position, and the transmission must be in the P (Park)
position for recreational towing.(Recreational towing is
not available on Quadra-Trac I equipped vehicles.)
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5. Raise the vehicle by turning the jack handle clockwise
until the tire clears the ground.
WARNING!
Raising the vehicle higher than necessary can make
the vehicle less stable and cause an accident. It could
slip off the jack and hurt someone near it. Raise the
vehicle only enough to remove the tire.
6. Remove the lug nuts and wheel.
7. Position the spare wheel/tire on the vehicle and install
the lug nuts with the cone-shaped end toward the wheel.
Lightly tighten the nuts until they are equally snug, using
a crisscross pattern. To avoid the risk of forcing the
vehicle off the jack, do not tighten the nuts fully until the
vehicle has been lowered.
8. Lower the vehicle and remove the jack and wheel
blocks.
Rear Jacking Location
244 WHAT TO DO IN EMERGENCIES

²Do not let anyone sit in the vehicle when it is on a jack.
²Do not get under the vehicle when it is on a jack.
²Only use the jack in the positions indicated.
²If working on or near a roadway, be extremely careful
of motor traffic.
JUMP STARTING PROCEDURE
NOTE:Check the charge indicator on top of the battery.
If the indicator is light or yellow, replace the battery.
1. Wear eye protection and remove any metal jewelry
such as watch bands or bracelets that might make an
unintended electrical contact.
2. When boost is provided by a battery in another
vehicle, park that vehicle within booster cable reach but
without letting the vehicles touch. Set the parking brake,
place the transmission in P (Park), and turn the ignition
to OFF for both vehicles.3. Turn off the heater, radio and all unnecessary electrical
loads.
4. Connect one end of a jumper cable to the positive
terminal of the discharged battery. Connect the other end
of the same cable to the positive terminal of the booster
battery.
5. Connect the other cable, first to the negative terminal
of the booster battery and then connect the other end to
a non-paint metal surface on the engine of the vehicle
with the discharged battery. Make sure you have a good
contact on the engine.
6. Start the engine in the vehicle which has the booster
battery, let the engine idle a few minutes, then start the
engine in the vehicle with the discharged battery.
7. When removing the jumper cables, reverse the above
sequence exactly. Be careful of the moving belts and fan.
246 WHAT TO DO IN EMERGENCIES