2004 JEEP GRAND CHEROKEE engine coolant

either too high or too low. Examine the gages carefully,
and follow the instructions above for each indicated
problem.
NOTE:When the ignition switch is turned to OFF, the
fuel gage, voltmeter, oil pressure, and temperature gages
will not show any readings. When the engine is not
running, turn the ignition switch to ON to obtain accu-
rate readings.
12. Part Time Indicator Light
This light alerts the driver that the vehicle is in
the PART TIME four±wheel drive mode, and
the front and rear driveshafts are mechanically
locked together forcing the front and rear wheels to rotate
at the same speed.
13. Transmission Over Temperature Warning Light
This light indicates that there is excessive transmis-
sion fluid temperature that might occur with severe
usage such as trailer towing or snow plowing. If this lightcomes on, stop the vehicle and run the engine at idle or
faster, with the transmission in N (Neutral) until the light
goes off.
14. Temperature Gage
Indicates engine coolant temperature. Any read-
ing within the normal range indicates that the
cooling system is operating satisfactorily.
The gage pointer will likely indicate a higher temperature
(above center scale) when driving in hot weather, up
mountain grades, or when towing a trailer. It should not
be allowed to exceed the upper limits of the normal
operating range.
If the pointer rises to the 260É (Hot) mark, pull over and
stop the vehicle. Do not turn the engine off. Idle the
vehicle with the air conditioning turned off, until the
pointer drops back into the normal range.
UNDERSTANDING YOUR INSTRUMENT PANEL 131
4

After Starting
The idle speed will automatically decrease as the engine
warms up.
CAUTION!
Long periods of engine idling, especially at high
engine speeds can cause excessive exhaust tempera-
tures which can damage your vehicle. Do not leave
your vehicle unattended with the engine running.
ENGINE BLOCK HEATER Ð IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the cord
to a standard 110-115 volt AC electrical outlet with
grounded, three wire extension cord.
Use the heater when temperatures below 0ÉF (-18ÉC) are
expected to last for several days.The engine block heater cord is located:
²6-cylinder engine Ð bundled and fastened to the
injector rail between injectors 1 and 2.
²V-8 engine Ð coiled and strapped to the transmission
filler tube.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110-115 volt AC electrical cord could
cause electrocution.
178 STARTING AND OPERATING

Over Temperature Mode
The transmission electronics constantly monitor the
transmission oil temperature. If the transmission gets too
hot, the transmission will change the way it shifts to help
control the condition. This may result in a slightly
different feeling or response during normal operation in
D (Drive) position. If the transmission becomes hot
enough the O/D OFF indicator light and TRANS OVER
TEMP warning light in the instrument cluster may come
on. After the transmission cools down, it will return to
normal operation.
Torque Converter Clutch
A feature designed to improve fuel economy has been
added to the automatic transmission of this vehicle. A
clutch within the torque converter engages automatically
at calibrated speeds. This may result in a slightly differ-
ent feeling or response during normal operation in high
gear. When the vehicle speed drops or during accelera-
tion, the clutch automatically and smoothly disengages.NOTE:
²The torque converter clutch will not engage until the
transmission fluid and engine coolant are warm (usu-
ally after 1±3 miles (1.6±4.8 km) of driving). Because
engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmis-
sion is not shifting into ªOverdriveº when cold. This is
considered a normal condition. Pressing the ªO/D
OFFº switch will show that the transmission is able to
shift into and out of ªOverdrive.º
²If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the trans-
mission into gear may seem sluggish. This is due to the
transmission fluid partially draining from the torque
converter into the transmission. This is considered a
normal condition and will not cause damage to the
transmission. The torque converter will refill within 5
seconds of shifting from P (Park) into any other gear
position.
STARTING AND OPERATING 185
5

WARNING!
Commercially available windshield washer solvents
are flammable. They could ignite and burn you. Care
must be exercised when filling or working around
the washer solution.
Exhaust System
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
If you notice a change in the sound of the exhaust system;
or if the exhaust fumes can be detected inside the vehicle;
or when the underside or rear of the vehicle is damaged;
have an authorized technician inspect the complete ex-
haust system and adjacent body areas for broken, dam-
aged, deteriorated, or mispositioned parts. Open seams
or loose connections could permit exhaust fumes to seepinto the passenger compartment. In addition, inspect the
exhaust system each time the vehicle is raised for lubri-
cation or oil change. Replace as required.
Cooling System
WARNING!
You 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 radia-
tor or coolant bottle is hot.
Coolant Checks
Check coolant protection every 12 months (before the
onset of freezing weather, where applicable). If coolant is
MAINTAINING YOUR VEHICLE 269
7

dirty or rusty in appearance, the system should be
drained, flushed and refilled with fresh coolant.
Check the front of the radiator for any accumulation of
bugs, leaves, etc. Clean the radiator by gently spraying
water from a garden hose at the back of the core.
Check the engine cooling system hoses for condition and
tightness of connection. Inspect the entire system for
leaks. Any hoses that show cuts or severe abrasion must
be replaced.
Cooling System Ð Drain, Flush, And Refill
At the intervals shown in the appropriate ªMaintenance
Schedule,º the system should be drained, flushed, and
refilled.
If the solution is dirty and contains a considerable
amount of sediment, clean and flush with reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals.
Engine Coolant Disposal
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. Do not store ethylene glycol-based engine
coolant in open containers or allow it to remain in
puddles on the ground. Prevent ingestion by animals and
children. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Selection Of Coolant
Use only the manufacturer's recommended coolant, refer
to Recommended Fluids, Lubricants, and Genuine Parts
for correct coolant type.
270 MAINTAINING YOUR VEHICLE

CAUTION!
²Mixing of coolants other than the specified HOAT
coolant may result in decreased corrosion protec-
tion and engine damage that may not be covered
under the new vehicle warranty. If a non-HOAT
coolant is introduced into the cooling system in an
emergency, it should be replaced with the speci-
fied coolant as soon as possible.
²Do not use plain water alone or alcohol base
antifreeze products. Do not use additional rust
inhibitors or antirust products, as they may not be
compatible with the radiator coolant and may
plug the radiator.
²This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propy-
lene Glycol base coolants is not recommended.
Adding Coolant
When adding coolant, a minimum solution of 50% rec-
ommended HOAT ethylene glycol coolant in water
should be used. Use higher concentrations (not to exceed
70%) if temperatures below -37ÉF (-38ÉC) are anticipated.
Use only high purity water such as distilled or deionized
water when mixing the water/antifreeze solution. 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 engine
coolant changes.
MAINTAINING YOUR VEHICLE 271
7

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 reserve tank.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
The warning words DO NOT OPEN HOT on the
cooling system pressure cap are a safety precaution.
Never add coolant when the engine is overheated.
Do not loosen or remove the cap to cool an over-
heated 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.
Coolant Level
Check the coolant level at least once a month or more
often in hot weather. Check the level when the engine is
at normal operating temperature. Check the coolant level
only in the coolant recovery bottle. The coolant level
must be between the FULL and the ADD mark on the
bottle.
272 MAINTAINING YOUR VEHICLE

See your authorized dealer if the coolant level drops
quickly.
Points To Remember
NOTE:When the vehicle is stopped after a few miles 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 accumulat-
ing on the radiator and being vaporized 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 bottle.
²Check coolant freeze point in the system.
²If frequent coolant additions are required, or if the
level in the recovery bottle does not drop when the
engine cools, the cooling system should be pressure
tested for leaks.
²Maintain coolant concentration at 50% ethylene glycol
antifreeze (minimum) in water for proper corrosion
protection of your engine that contains aluminum
components.
²Make sure that the radiator and coolant bottle hoses
are not kinked or obstructed.
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 cooling performance, poor gas
mileage, and increased emissions.
MAINTAINING YOUR VEHICLE 273
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