2007 JEEP GRAND CHEROKEE radiator

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.
JUMP STARTING
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, so follow this procedure
carefully.
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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, fol-
low the preceding safety tips.
Cooling System
WARNING!
²When working near the radiator cooling fan, dis-
connect the fan motor lead or turn the ignition
switch to the OFF position. The fan is temperature
controlled and can start at any time the ignition
switch is in the ON position.
²You or others can be badly burned by hot coolant
or steam from your radiator. If you see or hear
steam coming from under the hood, don't open
the hood until the radiator has had time to cool.
Never try to open a cooling system pressure cap
when the radiator is hot.
Coolant Checks
Check engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, where
318 MAINTAINING YOUR VEHICLE

applicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant. Check the front of the A/C condenser for any
accumulation of bugs, leaves, etc. If dirty, clean by gently
spraying water from a garden hose vertically down the
face of the condenser.
Check the coolant recovery bottle tubing for brittle rub-
ber, cracking, tears, cuts and tightness of the connection
at the bottle and radiator. Inspect the entire system for
leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
coolant from the radiator drain cock. If the cap is sealing
properly, the engine coolant (antifreeze) will begin to
drain from the coolant recovery bottle. DO NOT RE-
MOVE THE COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.Cooling System Ð Drain, Flush and Refill
At the intervals shown on the appropriate ªMaintenance
Schedule,º the system should be drained, flushed and
refilled.
If the solution is dirty or contains a considerable amount
of sediment, clean and flush with a reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals. Properly dispose of old
antifreeze solution.
Selection Of Coolant
Use only the manufacturer's recommended coolant, refer
to Fluids, Lubricants and Genuine Parts for correct
coolant type.
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CAUTION!
Mixing of coolants other than specified HOAT en-
gine coolants, may result in engine damage and may
decrease corrosion protection. If a non-HOAT cool-
ant is introduced into the cooling system in an
emergency, it should be replaced with the specified
coolant as soon as possible.
Do not use plain water alone or alcohol base engine
coolant (antifreeze) products. Do not use additional
rust inhibitors or antirust products, as they may not
be compatible with the radiator engine coolant and
may plug the radiator.
This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propylene
Glycol based coolants is not recommended.
Adding Coolant
Your vehicle has been built with an improved engine
coolant that allows extended maintenance intervals. This
coolant can be used up to 5 Years or 100,000 miles before
replacement. To prevent reducing this extended mainte-
nance period, it is important that you use the same
coolant throughout the life of your vehicle. Please review
these recommendations for using Hybrid Organic Addi-
tive Technology (HOAT) coolant.
When adding coolant, a minimum solution of 50% rec-
ommended Mopar Antifreeze/ Coolant 5 Year/100,000
Mile Formula HOAT (Hybrid Organic Additive Technol-
ogy), or equivalent, in water should be used. Use higher
concentrations (not to exceed 70%) if temperatures below
234ÉF (237ÉC ) are anticipated.
Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution.
320 MAINTAINING YOUR VEHICLE

The use of lower quality water will reduce the amount of
corrosion protection in the engine cooling system.
Please note that it is the owner's responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE:Mixing coolant types will decrease the life of the
engine coolant and will require more frequent coolant
changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
coolant, and to insure that coolant will return to the
radiator from the coolant recovery bottle.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
²The warning words ªDO NOT OPEN HOTº on
the cooling system pressure cap are a safety pre-
caution. Never add coolant when the engine is
overheated. Do not loosen or remove the cap to
cool an overheated engine. Heat causes pressure
to build up in the cooling system. To prevent
scalding or injury, do not remove the pressure cap
while the system is hot or under pressure.
²Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or
engine damage may result.
Disposal of Used Engine Coolant
Used ethylene glycol based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. To prevent ingestion by animals or children
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do not store ethylene glycol based engine coolant in open
containers or allow it to remain in puddles on the
ground. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine off and cold, the level of the coolant in the bottle
should be between the ranges indicated on the bottle.
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
coolant freeze point or replacing coolant. Advise your
service attendant of this. As long as the engine operating
temperature is satisfactory, the coolant bottle need only
be checked once a month.
When additional coolant is needed to maintain the
proper level, it should be added to the coolant bottle. Do
not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles (a
few kilometers) of operation, you may observe vapor
coming from the front of the engine compartment. This is
normally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot coolant to
enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
²Do not overfill the coolant recovery bottle.
²Check coolant freeze point in the radiator and in the
coolant recovery bottle. If antifreeze needs to be
added, contents of coolant recovery bottle must also be
protected against freezing.
322 MAINTAINING YOUR VEHICLE

²If frequent coolant additions are required, or if the
level in the coolant recovery bottle does not drop when
the engine cools, the cooling system should be pres-
sure tested for leaks.
²Maintain coolant concentration at 50% HOAT engine
coolant (minimum) and distilled water for proper
corrosion protection of your engine which contains
aluminum components.
²Make sure that the radiator and coolant recovery
bottle overflow hoses are not kinked or obstructed.
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, installONLY 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.
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Cav-
ityCartridge
FuseMini Fuse Description
18 20 Amp
YellowFront Control Module
(FCM) Batt #1
19 20 Amp
YellowLt Trailer-Tow Stop/
Turn
20 20 Amp
YellowFront Control Module
(FCM) Batt #3
21 20 Amp
YellowRt Trailer-Tow Stop/
Turn
22 30 Amp
PinkFinal Drive Control
Module (FDCM)
MOD
23 50 Amp
RedRadiator Fan
27 15 Amp
BlueIgnition Off Draw
(IOD) #1
28 20 Amp
YellowIgnition Off Draw
(IOD) #2Cav-
ityCartridge
FuseMini Fuse Description
29 10 Amp
RedOccupant Restraint
Controller (ORC) R/S
30 10 Amp
RedOccupant Restraint
Controller (ORC) R/O
VEHICLE STORAGE
If you are leaving your vehicle dormant for more than 21
days you may want to take steps to protect your battery.
You may:
²Remove fuse #27 in the Intelligent Power Module
labeled Ignition-Off Draw (IOD#1).
²Or, disconnect the negative cable from the battery.
²Anytime you store your vehicle, or keep it out of
service (i.e. vacation) for two weeks or more, run the
air conditioning system at idle for about five minutes
in the fresh air and high blower setting. This will
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