2012 JEEP GRAND CHEROKEE Owners Manual

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
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the SELECT button to turn off the message. If the
problem continues, the message will appear the next time
the vehicle is started.
A loose, improperly installed, or damaged fuel filler cap
may also turn on the Malfunction Indicator Light (MIL).
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.
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 II system is ready, you must
do the following:
1. Turn the ignition switch to the ON position, but do not
crank or start the engine.
2. If you crank or start the engine, you will have to start
this test over.
3. As soon as you turn the ignition switch to the ON
position, you will see the MIL symbol come on as part of
a normal bulb check.
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4. 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 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.
b. 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.
REPLACEMENT PARTS
Use of genuine MOPAR
parts for normal/scheduled
maintenance and repairs is highly recommended to en-
sure the designed performance. Damage or failures
caused by the use of non-MOPAR parts for maintenance
and repairs will not be covered by the manufacturer’s
warranty.
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DEALER SERVICE
Your authorized dealer has the qualified service person-
nel, 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 Service Manuals before
attempting any procedure yourself.
NOTE:Intentional tampering with emissions control
systems may void your warranty and could result in civil
penalties being assessed against you.
WARNING!
You can be badly injured working on or around a
motor vehicle. Only do service work for which you
have the knowledge and the proper equipment. If
you have any doubt about your ability to perform a
service job, take your vehicle to a competent me-
chanic.
MAINTENANCE PROCEDURES
The pages that follow contain the requiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides those maintenance items specified in the fixed
maintenance schedule, there are other components which
may require servicing or replacement in the future.
CAUTION!
•Failure to properly maintain your vehicle or per-
form repairs and service when necessary could
result in more costly repairs, damage to other
components or negatively impact vehicle perfor-
mance. Immediately have potential malfunctions
examined by an authorized Chrysler Group LLC
dealership or qualified repair center.
(Continued)
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CAUTION! (Continued)
•Your vehicle has been built with improved fluids
that protect the performance and durability of
your vehicle and also allow extended maintenance
intervals. Do not use chemical flushes in these
components as the chemicals can damage your
engine, transmission, power steering or air condi-
tioning. Such damage is not covered by the New
Vehicle Limited Warranty. If a flush is needed
because of component malfunction, use only the
specified fluid for the flushing procedure.
Engine Oil
Checking Oil Level
To assure proper engine lubrication, the engine oil must
be maintained at the correct level. Check the oil level at
regular intervals, such as every fuel stop. The best time tocheck the engine oil level is about five minutes after a
fully warmed engine is shut off, or before starting the
engine after it has sat overnight.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Maintain
the oil level in the SAFE level range. Adding 1 U.S. Quart
(0.95L) of oil when the level is at the bottom of the SAFE
range will result in the level being at the top of the SAFE
range.
CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
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Change Engine Oil
The oil change indicator system will remind you that it is
time to take your vehicle in for scheduled maintenance.
Refer to “Maintenance Schedule” for further information.
NOTE: Under no circumstances should oil change
intervals exceed 8,000 miles (13 000 km) or six months,
whichever occurs first.
Engine Oil Selection
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Cer-
tified and meet the requirements of Chrysler Material
Standard MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils.
CAUTION!
Do not use chemical flushes in your engine oil as the
chemicals can damage your engine. Such damage is
not covered by the New Vehicle Limited Warranty.
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Engine Oil Viscosity – 3.6L Engine
SAE 5W-30 engine oil is recommended for all operating
temperatures. This engine oil improves low temperature
starting and vehicle fuel economy.
The engine oil filler cap also shows the recommended
engine oil viscosity for your vehicle. For information on
engine oil filler cap location, refer to “Engine Compart-
ment” in “Maintaining Your Vehicle” for further informa-
tion.
Lubricants, which do not have both the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber, should not be used.
Engine Oil Viscosity – 5.7L Engine
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low temperature
starting and vehicle fuel economy.The engine oil filler cap also shows the recommended
engine oil viscosity for your vehicle. For information on
engine oil filler cap location, refer to “Engine Compart-
ment” in “Maintaining Your Vehicle” for further informa-
tion.
NOTE:
Vehicles equipped with a 5.7L engine must use
SAE 5W-20 oil. Failure to do so may result in improper
operation of the Multiple Displacement System (MDS).
Refer to “Multi-Displacement System” in “Starting and
Operating” for further information.
Lubricants, which do not have both the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber, should not be used.Synthetic Engine Oils
You may use synthetic engine oils if the recommended oil
quality requirements are met, and the recommended
maintenance intervals for oil and filter changes are
followed.
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Materials Added To Engine Oils
Do not add any supplemental materials, other than leak
detection dyes, to your engine oil. Engine oil is an
engineered product and its performance may be im-
paired by supplemental additives.
Disposing Of Used Engine Oil And Oil Filters
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact your local authorized dealer, ser-
vice station, or governmental agency for advice on how
and where used oil and oil filters can be safely discarded
in your area.
Engine Oil Filter
The engine oil filter should be replaced with a new filter
at every oil change.
Engine Oil Filter Selection
The manufacturer’s engines have a full-flow type dispos-
able oil filter. Use a filter of this type for replacement. The
quality of replacement filters varies considerably. Only
high-quality filters should be used to assure most effi-
cient service. MOPARengine oil filters are high-quality
oil filters and are recommended.
Engine Air Cleaner Filter
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
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