cooling JEEP GRAND CHEROKEE 2006 WK / 3.G SRT Owners Manual

13. Temperature Gauge
The temperature gauge shows engine coolant tempera-
ture. Any reading within the normal range indicates that
the engine cooling system is operating satisfactorily.
The gauge pointer will likely indicate a higher tempera-
ture 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.CAUTION!
Driving with a hot engine cooling system could
damage your vehicle. If temperature gauge reads (H),
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 “H”, and you hear continuous chimes, turn the
engine off immediately, and call for service.
WARNING!
A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. If you decide to look under the hood your-
self, refer to Section 7 of this manual. Follow the
warnings under “Cooling System Pressure Cap.”
180 UNDERSTANDING YOUR INSTRUMENT PANEL

CLIMATE CONTROLS
Automatic Temperature Control
The Infrared Dual-Zone Climate Control System auto-
matically maintains the interior comfort level desired by
the driver and passenger. This is accomplished by a dual
sun-sensor in the top of the instrument panel, and an
infrared sensor located in the face of the control unit.
There are also various sensors monitored by this system
which take account for vehicle speed, A/C pressure,
outside temperature, and engine cooling temperature.
The infrared sensor independently measures the surface
temperature of the driver and passenger. Based on the
sensor input, the system automatically adjusts the air
flow temperature, the air flow volume, and amount of
outside air recirculation. This maintains a comfortable
temperature even under changing conditions.NOTE:The numbers on the temperature dial represent
a comfort setting when the Mode knob is set to Auto, and
not the actual air temperature.
Operation of the system is quite simple. Begin by turning
the right mode knob to AUTO, and place the blower
control (left knob) to either LO AUTO or HI AUTO. The
Automatic Temperature Controls
222 UNDERSTANDING YOUR INSTRUMENT PANEL

This button can be used to block out smoke,
odors, dust, high humidity, or if rapid cooling
is desired. The recirculation mode should only
be used temporarily. The button includes an
LED that illuminates, which indicates that the recircula-
tion mode is active. You may use this feature separately.
NOTE:Extended use of recirculation may cause the
windows to fog. If the interior of the windows begins to
fog, press the “Recirculate” icon button to return to
outside air. Some temp./humidity conditions will cause
captured interior air to condense on windows and ham-
per visibility. For this reason, the system will not allow
“Recirculate” to be selected while in the defrost or
defrost/floor modes. Attempting to use the recirculation
while in these modes will cause the LED in the button to
blink and then turn off.Summer Operation
The engine cooling system in air conditioned vehicles
must be protected with a high-quality antifreeze coolant
to provide proper corrosion protection and to protect
against engine overheating. A 50% solution of ethylene
glycol antifreeze coolant in water is recommended. Refer
to “Maintenance Procedures” in Section 7 of this manual
for proper coolant selection.
Winter Operation
Use of the air Recirculation mode during winter months
is not recommended because it may cause window
fogging.
NOTE:Refer to the “Operating Tips” chart (for Manual
A/C Control) in this section for suggested control set-
tings in different weather conditions.
228 UNDERSTANDING YOUR INSTRUMENT PANEL

Towing Tips — Electronic Speed Control (If
Equipped)

Don’t use in hilly terrain or with heavy loads.
When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Towing Tips — Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, put transmission
in neutral and increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
refer to Cooling System Operating information in the
Maintenance section of this manual for more informa-
tion.
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.)
Recreational towing is not allowed.
STARTING AND OPERATING 285
5

IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
•On the highways — Slow down.
•In city traffic — 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 “H”,
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 “H”, and you hear continuous chimes, turn the
engine off immediately, and call for service.
JUMP STARTING PROCEDURE
NOTE:Check the charge indicator on the battery. If the
indicator is light or yellow, replace the battery.
1. Wear eye protection and remove any metal jewelry
such as watch bands or bracelets that might make an
unintended electrical contact.
WHAT TO DO IN EMERGENCIES 289
6

▫Power Steering Fluid Check..............310
▫Body Lubrication.....................311
▫Windshield Wiper Blades................312
▫Windshield Washers — Front And Rear.....312
▫Exhaust System......................313
▫Cooling System.......................314
▫Hoses And Vacuum/Vapor Harnesses.......319
▫Brake System........................319
▫Brake Fluid Level Check................321
▫Fuel System Hoses....................322
▫Automatic Transmission................323
▫Front And Rear Wheel Bearings...........324▫Appearance Care And Protection From
Corrosion...........................324

Fuse Panel...........................328
▫Interior Fuses........................328
▫Underhood Fuses (Power Distribution Center) . 330
▫Underhood Fuses (Integrated Power Module) . 332

Vehicle Storage........................334

Replacement Bulbs......................334

Bulb Replacement......................335
▫Head Light..........................335
▫Front Turn Signal.....................337
▫Front Fog Light......................338
▫Rear Tail, Stop, Turn Signal, And Back-Up
Lights.............................339
294 MAINTAINING YOUR VEHICLE

Cooling System
WARNING!
•When 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.
•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 radiator is hot.
Coolant Checks
Check engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, whereapplicable). 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.
314 MAINTAINING YOUR VEHICLE

Cooling System — Drain, Flush and Refill
At the intervals shown on the appropriate “Maintenance
Schedule,” 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.
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.
MAINTAINING YOUR VEHICLE 315
7

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

34°F (
37°C ) are anticipated.
Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant 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 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.
316 MAINTAINING YOUR VEHICLE

WARNING!
•The warning words “DO NOT OPEN HOT” 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.
•Do 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 childrendo 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.
MAINTAINING YOUR VEHICLE 317
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