2015 JEEP CHEROKEE catalytic converter

WARNING!(Continued)
Vehicle”. Follow the warnings under the Cooling
System Pressure Cap paragraph.
18. 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.
CAUTION!
Prolonged driving with the Malfunction Indicator
Light (MIL) on could cause damage to the engine
control system. It also could affect fuel economy and
driveability. If the MIL is flashing, severe catalytic
converter damage and power loss will soon occur.
Immediate service is required.
WARNING!
A malfunctioning catalytic converter, as referenced
above, can reach higher temperatures than in normal
operating conditions. This can cause a fire if you
drive slowly or park over flammable substances such
as dry plants, wood, cardboard, etc. This could result
in death or serious injury to the driver, occupants or
others.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 339

CAUTION!
To prevent damage to the starter, do not continuously
crank the engine for more than 10 seconds at a time.
Wait 10 to 15 seconds before trying again.
If Engine Fails To Start
WARNING!
•Never pour fuel or other flammable liquid into the
throttle body air inlet opening in an attempt to start
the vehicle. This could result in flash fire causing
serious personal injury.
(Continued)
WARNING!(Continued)
•Do not attempt to push or tow your vehicle to get it
started. Vehicles equipped with an automatic trans-
mission cannot be started this way. Unburned fuel
could enter the catalytic converter and once the
engine has started, ignite and damage the converter
and vehicle.
•If the vehicle has a discharged battery, booster
cables may be used to obtain a start from a booster
battery or the battery in another vehicle. This type
of start can be dangerous if done improperly. Refer
to “Jump Starting” in “What To Do In Emergen-
cies” for further information.
474 STARTING AND OPERATING

Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine perfor-
mance and damage the emissions control system.
•An 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 ser-
vice. Contact your authorized dealer for service
assistance.
(Continued)
CAUTION!(Continued)
•The 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 perfor-
mance problems resulting from the use of such
fuels or additives is not the responsibility of the
manufacturer.
NOTE:Intentional tampering with the emissions control
system can result in civil penalties being assessed against
you.
5
STARTING AND OPERATING 583

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.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
“CHECK GASCAP” message will be displayed in the
Electronic Vehicle Information Center (EVIC) or Driver
Information Display (DID). Refer to “Electronic Vehicle
Information (EVIC) or#Driver Information Display
(DID)” in “Understanding Your Instrument Panel” for
7
MAINTAINING YOUR VEHICLE 657

WARNING!(Continued)
•A hot exhaust system can start a fire if you park
over materials that can burn. Such materials might
be grass or leaves coming into contact with your
exhaust system. Do not park or operate your ve-
hicle in areas where your exhaust system can con-
tact anything that can burn.
CAUTION!
•The catalytic converter requires the use of un-
leaded fuel only. Leaded gasoline will destroy the
effectiveness of the catalyst as an emissions control
device and may seriously reduce engine perfor-
mance and cause serious damage to the engine.
(Continued)
CAUTION!(Continued)
•Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition.
In the event of engine malfunction, particularly
involving engine misfire or other apparent loss of
performance, have your vehicle serviced promptly.
Continued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
7
MAINTAINING YOUR VEHICLE 685

NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune-up to manufacturer’s specifica-
tions, should be obtained immediately.
To minimize the possibility of catalytic converter dam-
age:
•Do not shut off the engine or interrupt the ignition,
when the transmission is in gear and the vehicle is in
motion.
•Do not try to start the engine by pushing or towing the
vehicle.
•Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough
idle or malfunctioning operating conditions.
Cooling System
WARNING!
You or others can be badly burned by hot engine
coolant (antifreeze) or steam from your radiator. If
you see or hear steam coming from under the hood,
do not open the hood until the radiator has had time
to cool. Never try to open a cooling system pressure
cap when the radiator or coolant bottle is hot.
686 MAINTAINING YOUR VEHICLE