2004 JEEP WRANGLER service

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.
Locking Fuel Filler Cap (Gas Cap) Ð If Equipped
²
Turn the engine off.
²Insert the ignition key into the fuel cap, and turn the
key to the right to unlock the fuel cap. Rotate the fuel
cap to the left to remove.
²To replace the cap, insert it into the filler neck and
tighten the cap about 1/4 turn until you hear one click.
This is an indication that the cap is properly tightened.
²Make sure that the fuel cap tether strap is not caught
under the fuel cap.
²Be sure to remove the key.
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.
TRAILER TOWING
In this section you will find information on limits to the
type of towing you can reasonably do with your vehicle.
Before towing a trailer, carefully review 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.
Perform maintenance services as prescribed in the
ªMaintenance Schedulesº section. 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.
202 STARTING AND OPERATING

HAZARD WARNING FLASHER
The flasher switch is on top of the steering column, just
behind the steering wheel. Depress the switch and both
cluster indicators and all front and rear directional sig-
nals will flash. Depress the switch again to turn Hazard
Warning Flashers off.Do not use this emergency warning system when the
vehicle is in motion. Use it when your vehicle is disabled
and is creating a safety hazard for other motorists.
If it is necessary to leave the vehicle to go for service, the
flasher system will continue to operate with the ignition
key removed and the vehicle locked.
NOTE:With extended use, the flasher may wear down
your battery.
IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
²On the highways Ð Slow down.
²In city traffic Ð While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
removes this heat. You can also turn the Temperature
210 WHAT TO DO IN EMERGENCIES

Control to maximum heat, the Mode Control to floor, and
the Fan Control 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 ªHº,
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
the ªHº, and you hear continuous chimes, turn the
engine off immediately, and call for service.
CHANGING A FLAT TIRE
Tool Kit Location
The jack handle driver and jack extension are located in a
kit that is stored on the floor board to the right of the
front passenger seat. On some models, this tool kit is
under the carpeting in the same location.
Jack Location
The jack and lug wrench are stored under the front
passenger seat.
WHAT TO DO IN EMERGENCIES 211
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To remove the jack from its stowage position, carefully
release the rubber strap from the bracket. Turn the thumb
screw counterclockwise to loosen jack and then remove it
from the bracket.
WARNING!
Always store the jack, lug wrench, jack handle
driver, jack extension, and spare, flat or damaged tire
securely in the proper place. Never leave them loose
in the vehicle where they could become dangerous
projectiles during a quick stop or collision.
WARNING!
The jack is designed to use as a tool for changing
tires only. The jack should not be used to lift the
vehicle for service purposes, unless suitable sup-
ports are placed under the vehicle as a safety mea-
sure. The vehicle should be jacked on a firm level
surface only. Avoid ice or slippery areas.
CAUTION!
Never use your vehicle jack on the bumpers, sills or
underbody of your vehicle. Damage may result.
Place your vehicle jack only under an axle and in the
positions shown for ªTire Changing Procedures.º
212 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLE
CONTENTS
m2.4L Engine..........................223
m4.0L Engine..........................224
mOnboard Diagnostic System Ð OBD II......225
mEmissions Inspection And
Maintenance Programs
..................226
mReplacement Parts.....................227
mDealer Service........................227
mMaintenance Procedures.................228
NEngine Oil..........................228
NDrive Belts Ð Check Condition And Tension . . 231
NSpark Plugs.........................232
NCatalytic Converter....................232NEngine Timing Belt Ð 2.4L Engine.........233
NIgnition Wiring System Ð 2.4L Engine......233
NCrankcase Emission Control System........234
NFuel Filter..........................234
NEngine Air Cleaner Filter................234
NMaintenance-Free Battery................234
NAir Conditioner Maintenance.............235
NPower Steering Fluid Check..............236
NDriveline And Steering Component
Lubrication..........................237
NBody Lubrication.....................237
NWindshield Wiper Blades................237
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ONBOARD DIAGNOSTIC SYSTEM Ð OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the ªMalfunction Indicator Light.º It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
²Prolonged driving with the ªMalfunction Indica-
tor Lightº on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per-
formed.
²If the ªMalfunction Indicator Lightº is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur.
Immediate service is required.
MAINTAINING YOUR VEHICLE 225
7

EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle's OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn off
the ignition key or start the engine. This means that
your vehicle's OBD system isnot readyand you
shouldnotproceed to the I/M station.
b. The MIL will not flash at all and will remain fully
illuminated until you turn off the ignition key or
start the engine. This means that your vehicle's OBD
system isreadyand you can proceed to the I/M
station.
226 MAINTAINING YOUR VEHICLE

If your OBD system isnot ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive your
vehicle as you normally would in order for your OBD
system to update. A recheck with the above test routine
may then indicate that the system is now ready.
Regardless of whether your vehicle's OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have your
vehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.REPLACEMENT PARTS
Use of genuine Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Mopartparts for maintenance
and repairs will not be covered by the manufacturer's
warranty.
DEALER SERVICE
Your dealer has the qualified service personnel, special
tools and equipment to perform all service operations in
an expert manner. Service Manuals are available which
include detailed service information for your vehicle.
Refer to these manuals before attempting any procedure
yourself.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
MAINTAINING YOUR VEHICLE 227
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