2014 JEEP CHEROKEE OBD

WARNING!
A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. You may want to call an authorized dealer
for service if your vehicle overheats. If you decide to
look under the hood yourself, see “Maintaining Your
Vehicle”. Follow the warnings under the Cooling
System Pressure Cap paragraph.
16. Air Bag Warning Light This light will turn on for four to eight seconds
as a bulb check when the ignition switch is first
turned to the ON/RUN position. If the light is
either not on during starting, stays on, or turns
on while driving, have the system inspected at an autho-
rized dealer as soon as possible. Refer to “Occupant
Restraints” in “Things To Know Before Starting Your
Vehicle” for further information. 17. Malfunction Indicator Light (MIL)
The Malfunction Indicator Light (MIL) is part of
an Onboard Diagnostic system called OBD II that
monitors engine and automatic transmission con-
trol systems. The light will illuminate when the key is in
the ON/RUN position before engine start. If the bulb
does not come on when turning the key from OFF to
ON/RUN, have the condition checked promptly.
Certain conditions, such as a loose or missing gas cap,
poor fuel quality, etc., may illuminate the light after
engine start. The vehicle should be serviced if the light
stays on through several of your typical driving cycles. In
most situations, the vehicle will drive normally and will
not require towing.
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UNDERSTANDING YOUR INSTRUMENT PANEL 333

E-85 Usage In Non-Flex Fuel Vehicles
Non-Flex Fuel Vehicles (FFV) are compatible with gaso-
line containing 10% ethanol (E10). Gasoline with higher
ethanol content may void the New Vehicle Limited
Warranty.
If a Non-FFV vehicle is inadvertently fueled with E-85
fuel, the engine will have some or all of these symptoms:
•Operate in a lean mode.
• OBD II “Malfunction Indicator Light” on.
• Poor engine performance.
• Poor cold start and cold drivability.
• Increased risk for fuel system component corrosion. To fix a Non-FFV vehicle inadvertently fueled once with
E-85 perform the following:
•
Drain the fuel tank (see your authorized dealer).
• Change the engine oil and oil filter.
• Disconnect and reconnect the battery to reset the
engine controller memory.
More extensive repairs will be required for prolonged
exposure to E-85 fuel.
MMT In Gasoline
Methylcyclopentadienyl Manganese Tricarbonyl (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
522 STARTING AND OPERATING

MAINTAINING YOUR VEHICLE
CONTENTS
ENGINE COMPARTMENT — 2.4L ..........593
 ENGINE COMPARTMENT — 3.2L ..........594

ONBOARD DIAGNOSTIC SYSTEM — OBD II . . .595
▫ Loose Fuel Filler Cap Message ............596
 EMISSIONS INSPECTION AND
MAINTENANCE PROGRAMS .............596
 REPLACEMENT PARTS ..................598
 DEALER SERVICE ..................... .598
 MAINTENANCE PROCEDURES ...........598
▫ Engine Oil ......................... .600▫
Engine Oil Filter ..................... .603
▫ Engine Air Cleaner Filter ................603
▫ Maintenance-Free Battery ...............604
▫ Air Conditioner Maintenance .............605
▫ A/C Air Filter — If Equipped ............607
▫ Body Lubrication .....................607
▫ Windshield Wiper Blades ...............607
▫ Adding Washer Fluid ..................609
▫ Exhaust System ..................... .610
▫ Cooling System ..................... .612
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ONBOARD DIAGNOSTIC SYSTEM — 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 “Malfunction Indicator Light (MIL).” 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 authorized dealer for service as
soon as possible.
CAUTION!
•Prolonged driving with the MIL 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 performed.
• If the MIL is flashing while the engine is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
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MAINTAINING YOUR VEHICLE 595

Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
“gASCAP” message will display in the odometer or a
“CHECK gASCAP” message will be displayed in the
Electronic Vehicle Information Center (EVIC) or Driver
Information Display (DID). Refer to “Electronic Vehicle
Information Center (EVIC) or Driver Information Display
(DID)” in “Understanding Your Instrument Panel” for
further information. Tighten the gas cap until aclicking
sound is heard. This is an indication that the gas cap is
properly tightened.
Press the odometer reset button to turn the message off.
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 MIL. Resolving the problem will turn the
MIL light off.
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 that require an Inspection and Mainte-
nance (I/M), this check verifies the “Malfunction
Indicator Light (MIL)” is functioning and is not
on when the engine is running, and that the OBD II
system is ready for testing.
Normally, the OBD II system will be ready. The OBD II
system may notbe ready if your vehicle was recently
serviced, recently had a dead battery or a battery replace-
ment. If the OBD II system should be determined not
ready for the I/M test, your vehicle may fail the test.
596 MAINTAINING YOUR VEHICLE

Your vehicle has a simple ignition actuated test, which
you can use prior to going to the test station. To check if
your vehicle’s OBD II system is ready, you must do the
following:
1. Cycle the ignition switch to the ON position, but donot crank or start the engine.
NOTE: If you crank or start the engine, you will have to
start this test over.
2. As soon as you cycle the ignition switch to the ON position, you will see the MIL symbol come on as part
of a normal bulb check.
3. Approximately 15 seconds later, one of two things will happen:
• The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn OFF
the ignition or start the engine. This means that your
vehicle’s OBD II system is not readyand you should
not proceed to the I/M station. •
The MIL will not flash at all and will remain fully
illuminated until you turn OFF the ignition or start the
engine. This means that your vehicle’s OBD II system
is ready and you can proceed to the I/M station.
If your OBD II system is not 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 II
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 II system is
ready or not, if the MIL 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 is on with the engine
running.
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MAINTAINING YOUR VEHICLE 597