engine overheat JEEP GRAND CHEROKEE 2011 WK2 / 4.G Owners Manual

25. 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 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 an autho-
rized dealership for service.
WARNING!
A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. You may want to call an authorized dealer-
ship for service if your vehicle overheats. If you
decide to look under the hood yourself, see “Main-
taining Your Vehicle”. Follow the warnings under the
Cooling System Pressure Cap paragraph.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 257

vehicle is experiencing a problem with the charging
system. Obtain SERVICE IMMEDIATELY. See an autho-
rized dealer.
If jump starting is required, refer to “Jump Starting
Procedures” in “What To Do In Emergencies”.
•Electronic Throttle Control (ETC) LightThis light informs you of a problem with the
Electronic Throttle Control (ETC) system. The
light will come on when the ignition is first
turned ON and remain on briefly as a bulb
check. If the light does not come on during starting, have
the system checked by an authorized dealer.
If a problem is detected, the light will come on while the
engine is running. Cycle the ignition key when the
vehicle has completely stopped and the shift lever is
placed in the PARK position. The light should turn off. If the light remains lit with the engine running, your
vehicle will usually be drivable. However, see an autho-
rized dealer for service as soon as possible. If the light is
flashing when the engine is running, immediate service is
required and you may experience reduced performance,
an elevated/rough idle or engine stall and your vehicle
may require towing.
•Engine Temperature Warning Light
This light warns of an overheated engine condi-
tion. As temperatures rise and the gauge ap-
proaches H,this indicator will illuminate and a
single chime will sound after reaching a set threshold.
Further overheating will cause the temperature gauge to
pass H,the indicator will continuously flash and a
continuous chime will occur until the engine is allowed
to cool.
270 UNDERSTANDING YOUR INSTRUMENT PANEL

If the light turns on while driving, safely pull over and
stop the vehicle. If the A/C system is on, turn it off. Also,
shift the transmission into NEUTRAL and idle the ve-
hicle. If the temperature reading does not return to
normal, turn the engine off immediately and call for
service. Refer to “If Your Engine Overheats” in “What To
Do In Emergencies” for more information.
•Transmission Temperature Warning LightThis light indicates that there is excessive trans-
mission fluid temperature that might occur
with severe usage such as trailer towing. It may
also occur when operating the vehicle in a high
torque converter slip condition, such as 4-wheel-drive
operation (e.g., snow plowing, off- road operation). If this
light comes on, stop the vehicle and run the engine at idle
or faster, with the transmission in NEUTRAL until the
light goes off.
CAUTION!
Continuous driving with the Transmission Tempera-
ture Warning Light illuminated will eventually cause
severe transmission damage or transmission failure.
WARNING!
If the Transmission Temperature Warning Light is
illuminated and you continue operating the vehicle,
in some circumstances you could cause the fluid to
boil over, come in contact with hot engine or exhaust
components and cause a fire.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 271

Summer Operation
NOTE:In some cases during high temperature trailer
tow operation the Air Conditioning system performance
may be reduced. This is to help protect the engine from
overheating during the high load condition.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstructions.
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 ensure adequate
system lubrication to minimize the possibility of com-
pressor damage when the system is started again.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 335

•the engine coolant has reached normal operating tem-
perature;
•vehicle speed is above approximately 30 mph
(48 km/h);
•the TOW/HAUL switch has not been activated;
•transmission has reached normal operating temperature.
NOTE:If the vehicle is started in extremely cold tem-
peratures, the transmission may not shift into Overdrive
and will automatically select the most desirable gear for
operation at this temperature. Normal operation will
resume when the transmission fluid temperature has
risen to a suitable level. Refer to the “Note” under
“Torque Converter Clutch” in this section.
During cold temperature operation you may notice de-
layed upshifts, depending on engine and transmission
temperature. This feature improves the warm-up time of
the engine and transmission. If the transmission temperature gets extremely hot, the
transmission will automatically select the most desirable
gear for operation at this temperature. If the transmission
temperature becomes hot enough, the “TRANSMISSION
OVER TEMP” message may display, and the transmis-
sion may downshift out of Overdrive until the transmis-
sion cools down. After cool down, the transmission will
resume normal operation.
The transmission will downshift from Overdrive, to the
most desirable gear, if the accelerator pedal is fully
pressed at vehicle speeds above approximately 35 mph
(56 km/h).
When to Use TOW/HAUL Mode – If Equipped
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the TOW/HAUL switch. This will improve
performance and reduce the potential for transmission
overheating or failure due to excessive shifting. When
354 STARTING AND OPERATING

operating in TOW/HAUL mode, the transmission will
shift into direct gear and Overdrive will be enabled
under steady cruise conditions.
The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate when the switch has been
activated. Pressing the switch a second time restoresnormal operation. If the TOW/HAUL mode is desired,
the switch must be pressed each time the engine is
started.
In high ambient temperatures with sustained high engine
speed and load, an upshift, followed shortly thereafter by
a downshift, may occur. The “TOW/HAUL Indicator
Light” will turn off. This is a normal part of the overheat
protection strategy when operating in the TOW/HAUL
mode.
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 (3.6L engine) or in direct
gear (5.7L engine) until the vehicle is brought to a stop.
TOW/HAUL Switch
5
STARTING AND OPERATING 355

CAUTION! (Continued)
•An out-of-tune engine or certain fuel or ignition
malfunctions can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune
or malfunctioning and may require immediate
service. Contact your authorized dealer for service
assistance.
•The use of fuel additives, which are now being
sold as octane enhancers, is not recommended.
Most of these products contain high concentra-
tions of methanol. Fuel system damage or vehicle
performance problems resulting from the use of
such fuels or additives is not the responsibility of
the manufacturer.
NOTE: Intentional tampering with the emissions con-
trol system can result in civil penalties being assessed
against you.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
•Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas, which can
kill. Never run the engine in a closed area, such as
a garage, and never sit in a parked vehicle with the
engine running for an extended period. If the
vehicle is stopped in an open area with the engine
running for more than a short period, adjust the
ventilation system to force fresh, outside air into
the vehicle.
(Continued)
428 STARTING AND OPERATING

WHAT TO DO IN EMERGENCIES
CONTENTS
Hazard Warning Flashers ................ 462
 If Your Engine Overheats ................ 462
 Jacking And Tire Changing ............... 463
▫ Jack Location ....................... 464
▫ Spare Tire Stowage ................... 464
▫ Preparations For Jacking ............... 465
▫ Jacking Instructions ................... 466 
Jump-Starting ........................ 471
▫ Preparations For Jump-Start ............. 472
▫ Jump-Starting Procedure ............... 473
 Emergency Tow Hooks — If Equipped ...... 475
 Shift Lever Override ................... 476
 Towing A Disabled Vehicle ............... 477
▫ Towing Without The Ignition Key FOB ..... 479
▫ Two-Wheel Drive Models .............. 479
▫ Four-Wheel Drive Vehicles .............. 480
6

HAZARD WARNING FLASHERS
The Hazard Warning flasher switch is located on the
switch bank just above the climate controls.Press the switch to turn on the Hazard Warning
flasher. When the switch is activated, all directional
turn signals will flash on and off to warn oncoming
traffic of an emergency. Press the switch a second time to
turn off the Hazard Warning flashers.
This is an emergency warning system and it should not
be used when the vehicle is in motion. Use it when your
vehicle is disabled and it is creating a safety hazard for
other motorists.
When you must leave the vehicle to seek assistance, the
Hazard Warning flashers will continue to operate even
though the ignition is placed in the OFF position.
NOTE: With extended use the Hazard Warning flashers
may wear down your battery.
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, place the transmission
in NEUTRAL, but do not increase the engine idle
speed.
NOTE: There are steps that you can take to slow down
an impending overheat condition:
•If your air conditioner (A/C) is on, turn it off. The A/C
system adds heat to the engine cooling system and
turning the A/C off can help remove this heat.
462 WHAT TO DO IN EMERGENCIES

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, refer to “Safety Tips/Exhaust Gas” in “Things
To Know Before Starting Your Vehicle” for further
information.
•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
exhaust system. Do not park or operate your ve-
hicle in areas where your exhaust system can
contact anything that can burn.
CAUTION!
•The catalytic converter requires the use of un-
leaded fuel only. Leaded gasoline will destroy the
effectiveness of the catalyst as an emissions con-
trol device and may seriously reduce engine per-
formance and cause serious damage to the engine.
•Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition.
In the event of engine malfunction, particularly
involving engine misfire or other apparent loss of
performance, have your vehicle serviced promptly.
Continued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
500 MAINTAINING YOUR VEHICLE