2008 JEEP GRAND CHEROKEE air condition

IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
²On the highways Ð Slow down.
²In city traffic Ð While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
removes this heat. You can also turn the Temperature
Control to maximum heat, the Mode Control to floor, and
the Fan Control to High. This allows the heater core to act
as a supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads ªHº,
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the ªHº, and you hear continuous chimes, turn the
engine off immediately, and call for service.
WHAT TO DO IN EMERGENCIES 299
6

MAINTAINING YOUR VEHICLE
CONTENTS
mEngine Compartment ± 6.1L...............306
mOnboard Diagnostic System Ð OBD II........307
NLoose Fuel Filler Cap Message............308
mEmissions Inspection And Maintenance
Programs............................308
mReplacement Parts......................310
mDealer Service.........................310
mMaintenance Procedures..................311
NEngine Oil..........................311NEngine Oil Filter......................315
NDrive Belts Ð Check Condition And
Tensioner...........................315
NSpark Plugs.........................316
NEngine Air Cleaner Filter................316
NFuel Filter..........................317
NCatalytic Converter....................317
NMaintenance-Free Battery................318
NAir Conditioner Maintenance.............319
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Synthetic Engine Oils
You may use synthetic engine oils provided the recom-
mended oil quality requirements are met, and the recom-
mended maintenance intervals for oil and filter changes
are followed.
Materials Added to Engine Oil
The manufacturer strongly recommends against the ad-
dition of any additives (other than leak detection dyes) to
the engine oil. Engine oil is an engineered product and
it's performance may be impaired by supplemental ad-
ditives.
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 dealer, service 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 at every engine
oil change.
Engine Oil Filter Selection
The manufacturer's engines have a full-flow type 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 efficient
service. Mopar Engine Oil Filters are a high quality oil
filter and are recommended.
Drive Belts Ð Check Condition and Tensioner
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals, and replaced if re-
quired. See your authorized dealer for service.
MAINTAINING YOUR VEHICLE 315
7

At the mileage indicated on the appropriate ªMainte-
nance Schedule,º all belts and tensioner should be
checked for condition. Improper belt tension can cause
belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing, or frayed cords and replaced if there is indication
of damage which could result in belt failure. Low gen-
erator belt tension can cause battery failure.
Also check belt routing to make sure there is no interfer-
ence between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New spark plugs should be
installed at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Refer to ªFluids, Lubricants, and Genuine Partsº in
this section for spark plug information.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on ªMaintenance Schedule A.º If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on ªMaintenance Schedule B.º
WARNING!
The air cleaner can provide a measure of protection
in the case of engine backfire. Do not remove the air
cleaner unless such removal is necessary for repair or
maintenance. Make sure that no one is near the
engine compartment before starting the vehicle with
the air cleaner removed. Failure to do so can result in
serious personal injury.
316 MAINTAINING YOUR VEHICLE

CAUTION!
It is essential when replacing the cables on the
battery that the positive cable is attached to the
positive post and the negative cable is attached to the
negative post. Battery posts are marked (+) positive
and negative (-) and identified on the battery case.
Also, if a ªfast chargerº is used while battery is in the
vehicle, disconnect both vehicle battery cables before
connecting the charger to battery. Do not use a ªfast
chargerº to provide starting voltage.
Air Conditioner Maintenance
For best possible performance, your air conditioner
should be checked and serviced by an Authorized Dealer
at the start of each warm season. This service shouldinclude cleaning of the condenser fins and a performance
test. Drive belt tension should also be checked at this
time.
WARNING!
²Use only refrigerants and compressor lubricants
approved by the manufacturer for your air condi-
tioning system. Some unapproved refrigerants are
flammable and can explode, injuring you. Other
unapproved refrigerants or lubricants can cause
the system to fail, requiring costly repairs. Refer
to Section 3 of the Warranty Information Book for
further warranty information.
²The air conditioning system contains refrigerant
under high pressure. To avoid risk of personal
injury or damage to the system, adding refrigerant
or any repair requiring lines to be disconnected
should be done by an experienced repairman.
MAINTAINING YOUR VEHICLE 319
7

NOTE:Use only manufacturer approved A/C System
Sealers, Stop Leak Products, Seal Conditioners, Compres-
sor Oil, or Refrigerants.
Refrigerant Recovery and Recycling
R-134a Air Conditioning Refrigerant is a hydrofluorocar-
bon (HFC) that is endorsed by the Environmental Pro-
tection Agency and is an ozone-saving product. How-
ever, the manufacturer recommends that air conditioning
service be performed by dealers or other service facilities
using recovery and recycling equipment.
Power Steering Fluid Check
The power steering system requires the use of Mopart
Hydraulic System Power Steering Fluid (P/N
05142893AA), or equivalent, which meets
DaimlerChrysler Material Standard MS-10838.
CAUTION!
Do not use Automatic Transmission Fluid (ATF) or
other types of power steering fluids when servicing
the power steering system of this vehicle. Damage to
the power steering system can result from the use of
the wrong power steering fluid.
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
ªDaimlerChrysler Dealership.º
320 MAINTAINING YOUR VEHICLE

²Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
²Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory coolant performance, poor gas
mileage, and increased emissions.
Hoses And Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to those hoses nearest to high
heat sources such as the exhaust manifold. Inspect hose
routing to be sure hoses do not come in contact with any
heat source or moving component which may cause heat
damage or mechanical wear.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.
Components should be replaced immediately if there is
any evidence of wear or damage that could cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Suggested service intervals can be found on the appro-
priate ªMaintenance Schedule.º Refer to Section 8 of this
manual.
MAINTAINING YOUR VEHICLE 329
7

Cav-
ityCartridge
FuseMini Fuse Description
3 10 Amp
RedHtd Mirror (EBL)
4 20 Amp
YellowRr Pwr Out (B+)
5 10 Amp
RedRr HVAC (R/O)
(Commander Only)
6 Spare (B+)
7 20 Amp
YellowDoor Locks (B+)
8 15 Amp
BlueSteer Col Lock (B+)
(ELV)
9 20 Amp
YellowPwr Outlet (B+)Cav-
ityCartridge
FuseMini Fuse Description
10 10 Amp
RedFinal Drive Control
Module (FDCM),
Heater Ventilation, Air
Conditioning (HVAC),
Switch Bank, Transfer
Case Switch, O/H,
Heater Ventilation, Air
Conditioning (HVAC)
Relay, Rear Park As-
sist
11 Spare (B+)
12 10 Amp
RedDoor Mods, Mem. Sw,
O/H Lamps, IP Cour-
tesy Lamps, Glove
Box Lamp (B+)
13 10 Amp
RedAutowipe (R/A)
MAINTAINING YOUR VEHICLE 339
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