2007 JEEP GRAND CHEROKEE light

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.
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Loose Fuel Filler Cap Message
After fuel is added, the vehicle diagnostic system can
determine if the fuel filler cap is loose, improperly
installed, or damaged. A ªCHECK GASCAPº message
will be displayed in the EVIC (Refer to Section 4 of this
manual). Tighten the gas cap until a9clicking9sound is
heard. This is an indication that the gas cap is properly
tightened.
This message may be temporarily overridden by pressing
either the C/T, STEP, or MENU buttons. However, after
one minute of no customer interaction, the EVIC will
display again the ªCHECK GASCAPº message. The
message will remain displayed until the vehicle diagnos-
tic system can retest the fuel system. The test will
perform the next time the vehicle is started, if the vehicle
was keyed off above 40ÉF (4ÉC) outside temperature and
the following vehicle start is above 40ÉF (4ÉC) outside
temperature. It may be possible to have a message that
will not clear due to the test being disabled due to lowoutside temperatures. If the test is performed and the
problem is gone, the message will disappear.
If the problem persists, the message will appear the next
time the vehicle is started. This might indicate a damaged
cap. If the problem is detected twice in a row, the system
will turn on the Malfunction Indicator Light (MIL).
Resolving the problem will turn the MIL light off. See
your authorized dealer for service.
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)
302 MAINTAINING YOUR VEHICLE

Body Lubrication
Locks and all body pivot points, including such items as
seat tracks, doors, trunk and hood hinges, should be
lubricated periodically to assure quiet, easy operation
and to protect against rust and wear. Prior to the appli-
cation of any lubricant, the parts concerned should be
wiped clean to remove dust and grit; after lubricating
excess oil and grease should be removed. Particular
attention should also be given to hood latching compo-
nents to insure proper function. When performing other
underhood services, the hood latch, release mechanism
and safety catch should be cleaned and lubricated.
The external lock cylinders should be lubricated twice a
year, preferably in the fall and spring. Apply a small
amount of a high quality MopartLock Cylinder Lubri-
cant or equivalent directly into the lock cylinder.
Windshield Wiper Blades
The rubber edges of the wiper blades and the windshield
should be cleaned periodically with a sponge or soft cloth
and a mild nonabrasive cleaner. This will remove accu-
mulations of salt or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.
Avoid using the wiper blades to remove frost or ice from
the windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Windshield Washers Ð Front and Rear
On vehicles equipped with a Electronic Vehicle Informa-
tion Center (EVIC), the low washer fluid level will be
indicated. When the sensor detects a low fluid level, the
windshield will light on the vehicle graphic outline and
316 MAINTAINING YOUR VEHICLE

Insure nylon tubing in these areas has not melted or
collapsed.
Inspect all hose connections such as clamps and cou-
plings to make sure they are secure and no leaks are
present.
NOTE:Often, fluid such as oil, power steering fluid,
and brake fluid are used during assembly plant opera-
tions to facilitate the assembly of hoses to couplings.
Therefore, oil wetness at the hose-coupling area is not
necessarily an indication of leakage. Actual dripping of
hot fluid when systems are under pressure (during
vehicle operation), should be noted before a hose is
replaced based on leakage.
NOTE:Inspection of brake hoses should be performed
whenever the brake system is serviced and at every
engine oil change. Inspect hydraulic brake hoses for
surface cracking, scuffing, or worn spots. If there is any
evidence of cracking, scuffing, or worn spots, the hoseshould be replaced immediately! Eventual deterioration
of the hose can take place resulting in a possibility of a
burst failure.
WARNING!
Worn brake hoses can burst and cause brake failure.
You could have an accident. If you see any signs of
cracking, scuffing, or worn spots, have the brake
hoses replaced immediately.
Brake Fluid Level Check
The fluid level in the master cylinder should be checked
when performing underhood services, or immediately if
the brake system warning light indicates system failure.
Clean the top of the master cylinder area before removing
the cap. Add fluid to bring the level up to the top of the
ªFULLº mark on the side of the master cylinder reservoir.
MAINTAINING YOUR VEHICLE 325
7

insure adequate system lubrication to minimize the
possibility of compressor damage when the system is
started again.
REPLACEMENT BULBS
Interior Lights Bulb Type
Glove Box Light......................... 194
Grab Handle Light................L002825W5W
Overhead Console Reading Lights..........VT4976
Rear Cargo Light.......................214±2
Visor Vanity Light.....................V26377
Underpanel Courtesy Lights................. 906
Instrument Cluster (General Illumination)....... 103
Telltale/Hazard Light...................... 74
* Available only from authorized dealers.Exterior Lights Bulb Type
Backup Lights.........................3157K
Front Fog Lights........................9145
Front Park/Turn Light...................3157K
Front Side Marker.......................2825
Headlights (Low Beam)...................9006
Headlights (High Beam)...................9005
Rear License Plate Light.................... 168
Rear Stop/Tail Lights....................3157K
Rear Turn/Tail Lights (2)..................3157
NOTE:Numbers refer to commercial bulb types that
can be purchased from your authorized dealer.
If a bulb needs to be replaced, visit your authorized
dealer or refer to the applicable Service Manual.
340 MAINTAINING YOUR VEHICLE

BULB REPLACEMENT
Head Light
1. Open the hood.
2. Remove the headlamp cover.3. Turn the low or high beam bulb 1/4 turn counter
clockwise to remove from housing.
4. Disconnect the electrical connector and replace the
bulb.
MAINTAINING YOUR VEHICLE 341
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3. Turn the turn signal bulb 1/4 turn counter clockwise
to remove from housing.
4. Disconnect the electrical connector and replace the
bulb.CAUTION!
Do not touch the new bulb with your fingers. Oil
contamination will severely shorten bulb life. If the
bulb comes in contact with any oily surface, clean
the bulb with rubbing alcohol.
Front Fog Light
1. Reach behind the front fascia from under the vehicle.
2. Turn the front fog light bulb 1/4 turn counter clock-
wise to remove from housing.
3. Disconnect the electrical connector and replace bulb.
MAINTAINING YOUR VEHICLE 343
7

CAUTION!
Do not touch the new bulb with your fingers. Oil
contamination will severely shorten bulb life. If the
bulb comes in contact with any oily surface, clean
the bulb with rubbing alcohol.
Rear Tail, Stop, Turn Signal, and Back-Up Lights
1. Raise the liftgate.
2. Remove the two Torx fasteners.
344 MAINTAINING YOUR VEHICLE