2006 JEEP GRAND CHEROKEE cooling

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.”
14. Electronic Vehicle Information Center Display
When the appropriate conditions exist, this display shows
the Electronic Vehicle Information Center (EVIC) mes-
sages. Refer to“Electronic Vehicle Information Center”
later in this section. (See page 187 for more information.)
15. TOW/HAUL Indicator Light
This light will illuminate when the TOW/
HAUL button has been selected. The TOW/
HAUL button is located in the center of the
instrument panel (below the climate controls).
184 UNDERSTANDING YOUR INSTRUMENT PANEL

Automatic Temperature Control—If Equipped
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
238 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.
244 UNDERSTANDING YOUR INSTRUMENT PANEL

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.)
Towing–2WD Models
Recreational towing is allowed ONLY if the driveshaft
is removed.Towing with the rear wheels on the ground
while the driveshaft is connected can result in severe
transmission damage.
Towing—Quadra-Trac I (Single-Speed Transfer
Case) 4WD Models
Recreational towing is not allowed.This model does not
have a N (Neutral) position in the transfer case.
320 STARTING AND OPERATING

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.
WHAT TO DO IN EMERGENCIES 329
6

▫Air Conditioner Maintenance.............359
▫Power Steering Fluid Check..............360
▫Body Lubrication.....................362
▫Windshield Wiper Blades................362
▫Windshield Washers—Front And Rear.....362
▫Exhaust System......................363
▫Cooling System.......................364
▫Hoses And Vacuum/Vapor Harnesses.......369
▫Brake System........................369
▫Automatic Transmission................371
▫Transfer Case........................374
▫Front/Rear Axle Fluid..................375▫Appearance Care And Protection From
Corrosion...........................376

Fuse Panel...........................380
▫Interior Fuses........................380
▫Underhood Fuses
(Power Distribution Center)..............382
▫Underhood Fuses
(Integrated Power Module)..............384

Vehicle Storage........................385

Replacement Bulbs......................386

Bulb Replacement......................387
▫Head Light..........................387
▫Front Turn Signal.....................388
▫Front Fog Light......................389
342 MAINTAINING YOUR VEHICLE

Cooling System
WARNING!
You or others can be badly burned by hot antifreeze/
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 or coolant bottle is hot.
Engine Coolant Checks
Check antifreeze/coolant protection every 12 months
(before the onset of freezing weather, where applicable).
If antifreeze/coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
antifreeze/coolant. Check the front of the A/C condenserfor 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 engine cooling system hoses for brittle rubber,
cracking, tears, cuts, and tightness of the connection at
the coolant recovery 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 antifreeze/coolant will begin to drain from
the coolant recovery bottle. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE COOLING
SYSTEM IS HOT.
364 MAINTAINING YOUR VEHICLE

Cooling System—Drain, Flush, And Refill
At the intervals shown in the appropriate“Maintenance
Schedule,”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. Properly dispose of old
antifreeze/coolant solution.
Selection Of Engine Coolant
Use only the manufacturer’s recommended antifreeze/
coolant, refer to Fluids, Lubricants, and Genuine Parts for
correct antifreeze/coolant type.
CAUTION!
Mixing of antifreeze/coolant other than the specified
HOAT antifreeze/coolant may result in decreased
corrosion protection and engine damage. If a non-
HOAT antifreeze/coolant is introduced into the cool-
ing system in an emergency, it should be replaced
with the specified antifreeze/coolant as soon as pos-
sible.
Do not use plain water alone or alcohol base
antifreeze/coolant products. Do not use additional
rust inhibitors or antirust products, as they may not
be compatible with the antifreeze/coolant and may
plug the radiator.
This vehicle has not been designed for use with
Propylene Glycol based antifreeze/coolant. Use of
Propylene Glycol base antifreeze/coolant is not rec-
ommended.
MAINTAINING YOUR VEHICLE 365
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