catalytic converter JEEP GRAND CHEROKEE 2012 WK2 / 4.G Owners Manual

INSTRUMENT CLUSTER DESCRIPTIONS
1. Tachometer
Indicates the engine speed in revolutions per minute
(RPM x 1000).
2. Air Bag Warning LightThis 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.
3. 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 MIL on could cause
damage to the engine control system. It also could
affect fuel economy and drivability. If the MIL is
flashing, severe catalytic converter damage and
power loss will soon occur. Immediate service is
required.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 285

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. Electronic Stability Control (ESC) Activation/
Malfunction Indicator Light — If Equipped The “ESC Activation/Malfunction Indicator
Light” in the instrument cluster will come on
when the ignition switch is turned to the
ON/RUN position. It should go out with the
engine running. If the “ESC Activation/Malfunction In-
dicator Light” comes on continuously with the engine
running, a malfunction has been detected in the ESC system. If this light remains on after several ignition
cycles, and the vehicle has been driven several miles
(kilometers) at speeds greater than 30 mph (48 km/h), see
your authorized dealer as soon as possible to have the
problem diagnosed and corrected.
NOTE:
•The “ESC Off Indicator Light” and the “ESC
Activation/Malfunction Indicator Light” come on mo-
mentarily each time the ignition switch is turned to
ON/RUN.
•Each time the ignition is turned to ON/RUN, the ESC
system will be ON, even if it was turned off previously.
•The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver
that caused the ESC activation.
286 UNDERSTANDING YOUR INSTRUMENT PANEL

•Press the ENGINE START/STOP button a second time
to change the ignition switch to the RUN position
(EVIC displays “IGNITION MODE RUN”),
•Press the ENGINE START/STOP button a third time
to return the ignition switch to the OFF position (EVIC
displays “IGNITION MODE OFF”).
Extreme Cold Weather (Below –20°F Or29°C)
To ensure reliable starting at these temperatures, use of
an externally powered electric engine block heater (avail-
able from your authorized dealer) is recommended.
If Engine Fails To Start
WARNING!
•Never pour fuel or other flammable liquids into
the throttle body air inlet opening in an attempt to
start the vehicle. This could result in a flash fire
causing serious personal injury.
•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 improp-
erly. Refer to “Jump Starting” in “What To Do In
Emergencies” for further information.
5
STARTING AND OPERATING 417

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 and they would result in additional cost.
Therefore, you should not have to add anything to the
fuel.
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.(Continued)
CAUTION! (Continued)
•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
service. Contact your authorized dealer for service
assistance.
•The use of fuel additives, which are now being
sold as octane enhancers, is not recommended.
Most of these products contain high concentra-
tions of methanol. Fuel system damage or vehicle
performance problems resulting from the use of
such fuels or additives is not the responsibility of
the manufacturer.
NOTE: Intentional tampering with the emissions con-
trol system can result in civil penalties being assessed
against you.
512 STARTING AND OPERATING

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 drivability. 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 loose gascap indicator
will display in the EVIC telltale display area.
Refer to “Electronic Vehicle Information Center (EVIC)”
in “Understanding Your Instrument Panel” for further
information. Tighten the fuel filler cap properly and press
7
MAINTAINING YOUR VEHICLE 575

WARNING!
•Exhaust gases can injure or kill. They contain
carbon monoxide (CO), which is colorless and
odorless. Breathing it can make you unconscious
and can eventually poison you. To avoid breathing
CO, refer to “Safety Tips/Exhaust Gas” in “Things
To Know Before Starting Your Vehicle” for further
information.
•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
contact 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 con-
trol device and may seriously reduce engine per-
formance and cause serious damage to the engine.
•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.
590 MAINTAINING YOUR 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.
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.
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MAINTAINING YOUR VEHICLE 591