2006 JEEP GRAND CHEROKEE heating

Vacation Storage
Anytime you store your vehicle, or keep it out of service
(i.e. vacation) for two weeks or more, run the air condi-
tioning system at idle for about five minutes in the fresh
air and high blower setting. This will insure adequate
system lubrication to minimize the possibility of com-
pressor damage when the system is started again.
Window Fogging
Interior fogging on the windshield can be quickly re-
moved by turning the mode selector to Defrost, and
turning on the high blower. The Defrost/Floor mode can
be used to maintain a clear windshield and provide
sufficient heating. If side window fogging becomes a
problem increase blower speed. Vehicle windows tend to
fog on the inside in mild but rainy or humid weather.
NOTE:Recirculate without A/C should not be used for
long periods as fogging may occur.
Outside Air Intake
Make sure the air intake, located directly in front of the
windshield, is free of obstructions such as leaves. Leaves
collected in the air intake may reduce airflow and if they
enter the plenum they could plug the water drains. In
winter months make sure the air intake is clear of ice,
slush and snow.
UNDERSTANDING YOUR INSTRUMENT PANEL 245
4

overheating or failure due to excessive shifting. When
operating in“TOW/HAUL”mode, the transmission will
shift to 3rd gear and 4th will be enabled under steady
cruise conditions.
The“TOW/HAUL”light will illuminate in the instru-
ment cluster to indicate when the switch has beenactivated. Pressing the switch a second time restores
normal operation. If the“TOW/HAUL”mode is desired,
the switch must be pressed each time the engine is
started.
Transmission Limp Home Mode
Transmission function is monitored for abnormal condi-
tions. If a condition is detected that could result in
transmission damage, the transmission limp home mode
will be engaged. In this mode, the transmission will
remain in the current gear until the vehicle is brought to
a stop.
To reset the transmission, use the following procedure:
1. Stop the vehicle.
2. Move the shift lever to the P (Park) position.
3. Turn off the engine, be sure to turn the key to the
LOCK position.
Tow/Haul Button
STARTING AND OPERATING 259
5

cause damage to the transmission. The torque converter
will refill within five seconds of shifting from Park into
any other gear position.
Rocking the Vehicle
If the vehicle becomes stuck in snow, sand, or mud, it can
often be moved by a rocking motion. Move the gear
selector rhythmically between D (Drive) and R (Reverse),
while applying slight pressure to the accelerator.
NOTE:The Electronic Stability Program (ESP) and
Traction Control (if equipped) should be turned OFF
before attempting to rock the vehicle. Refer to“Electronic
Brake Control System”in Section 3 of this manual.
The least amount of accelerator pedal pressure to main-
tain the rocking motion without spinning the wheels or
racing the engine is most effective. Racing the engine or
spinning the wheels, due to the frustration of not freeing
the vehicle, may lead to transmission overheating and
failure. Allow the engine to idle with the transmissionselector in N (Neutral) for at least one minute after every
five rocking-motion cycles. This will minimize overheat-
ing and reduce the risk of transmission failure during
prolonged efforts to free a stuck vehicle.
CAUTION!
When“rocking”a stuck vehicle by moving between
“First”and R (Reverse), do not spin the wheels faster
than 15 mph (24 km/h), or drivetrain damage may
result.
STARTING AND OPERATING 261
5

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

CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your ex-
haust system. Do not park or operate your vehicle in
areas where your exhaust system can contact any-
thing that can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune up to manufacturer’s specifica-
tions, should be obtained immediately.
356 MAINTAINING YOUR VEHICLE

Engine
Air Cleaner.......................... 358
Block Heater......................... 253
Break-In Recommendations................ 68
Compartment......................... 345
Cooling............................. 364
Exhaust Gas Caution..................69,305
Fails to Start.......................... 252
Flooded, Starting...................... 252
Fuel Requirements..................302,392
Jump Starting......................... 336
Oil ..............................351,392
Oil Change Interval.................... 351
Oil Disposal.......................... 354
Oil Filter............................ 354
Oil Filter Disposal...................... 354
Oil Selection.......................... 392
Overheating.......................... 329
Starting............................. 251Temperature Gauge..................... 184
Engine Oil Viscosity...................... 353
Engine Oil Viscosity Chart................. 353
Enhanced Accident Response Feature.......... 55
Entry System, Illuminated.................. 16
Event Data Recorder...................... 56
Exhaust Gas Caution...................69,305
Exhaust System......................... 363
Exterior Finish Care...................... 376
Filters
Air Cleaner.......................... 358
Engine Oil........................... 354
Finish Care............................ 376
Flashers.............................. 328
Hazard Warning....................... 328
Turn Signal.....................180,388,390
Flipper Glass, Liftgate..................... 26
Flooded Engine Starting................... 252
428 INDEX

Rearview............................. 78
Vanity............................... 82
Modifications/Alterations, Vehicle............. 8
Monitor, Tire Pressure System............... 294
Mopar Parts.........................349,419
Multi-Displacement Engine System........... 278
Multi-Function Control Lever............... 121
New Vehicle Break-In Period................ 68
Occupant Restraints....................... 31
Octane Rating, Gasoline (Fuel).............. 302
Odometer..........................184,185
Trip ................................ 184
Off-Pavement Driving (Off-Road)..........274,375
Off-Road Driving (Off-Pavement)..........274,375
Oil, Engine............................ 351
Capacity............................ 392
Change Interval....................... 351Dipstick............................. 351
Filter............................... 354
Identification Logo..................... 353
Materials Added to..................... 354
Pressure Warning Light.................. 182
Recommendation...................352,392
Viscosity..........................353,392
Onboard Diagnostic System..............347,348
Opener, Garage Door (HomeLink) ........... 152
Outside Rearview Mirrors.................. 80
Overdrive............................. 257
Overdrive OFF Switch.................... 257
Overhead Console....................... 151
Overheating, Engine...................184,329
Owner’s Manual (Operator Manual).......... 420
Paint Care............................. 376
Paint Damage.......................... 376
Panic Alarm............................ 22
434 INDEX