2007 JEEP GRAND CHEROKEE light

If the engine shows no sign of starting after two 15
second periods of cranking with the accelerator pedal
held to the floor, the normal starting procedure should be
repeated.
WARNING!
Never pour fuel or other flammable liquids into the
throttle body air inlet opening in an attempt to start
the vehicle. This could result in a flash fire causing
serious personal injury.
Normal Starting — Diesel Engines
1. Turn the ignition key to the ON position.
2. Watch for the “Glow Plug Indicator Light” in the
instrument cluster. Refer to “Instrument Cluster” in
Section 4. It will glow for two to ten seconds or more,depending on engine temperature. When the “Glow Plug
Indicator Light” goes out, the engine is ready to start.
3.Do notpress the accelerator. Turn the ignition key
briefly to START position, and release it. The starter
motor will continue to run, but will automatically disen-
gage itself when the engine is running.
NOTE:The starter motor may run up to 30 seconds in
very cold conditions until the engine is started. The
starter can be disengaged by turning the ignition key to
the OFF position, if required.
4. After the engine starts, allow it to idle for approxi-
mately 30 seconds before driving. This allows oil to
circulate and lubricate the turbocharger.
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In high ambient temperatures with sustained high engine
speed and load, an upshift followed shortly thereafter by
a downshift may occur. This is a normal part of the
overheat protection strategy when operating in the
“Tow/Haul” mode.
The transmission will downshift from Overdrive to the
most desirable gear if the accelerator pedal is fully
depressed 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” button. This will improve
performance and reduce the potential for transmission
overheating or failure due to excessive shifting. When
operating in “TOW/HAUL” mode, the transmission will
shift to direct gear and Overdrive will be enabled under
steady cruise conditions.The “TOW/HAUL” light will illuminate in the instru-
ment cluster to indicate when the switch has been
activated. 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.
Tow/Haul Button
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5

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 (3.7L engine) or in direct gear
(4.7L and 5.7L engines) 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.
4. Wait approximately 10 seconds, then restart the en-
gine.
5. Move the shift lever to the desired gear range.If the problem is no longer detected, the transmission will
return to normal operation. If the problem persists, P
(Park), R (Reverse), and N (Neutral) will continue to
operate. Only 2nd gear (3.7L engine) or 3rd gear (4.7L
and 5.7L engines) will be available in the D (Drive)
position. Have the transmission checked at your autho-
rized dealer as soon as possible.
Torque Converter Clutch
A feature, designed to improve fuel economy, has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at a calibrated speed at light throttle. It engages at
higher speeds under heavier acceleration. This may re-
sult in a slightly different feeling or response during
normal operation in high gear. When the vehicle speed
drops below a calibrated speed, or during acceleration,
the clutch automatically and smoothly disengages. The
feature is operational in Overdrive and in Drive.
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NOTE:The torque converter clutch will not engage
until the transmission fluid and engine coolant are warm
[usually after 1-3 miles (1.6 - 4.8 km) of driving]. Because
the engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmission
is not shifting into Overdrive when cold. This is normal.
Manually shifting (using the ERS shift control) between 4
(direct gear) and 5/D (Overdrive gear) positions will
demonstrate that the transmission is able to shift into and
out of Overdrive.
NOTE:If the vehicle has not been driven in several
days, the first few seconds of operation after shifting the
transmission into gear may seem sluggish. This is due to
the fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
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 transmission
selector in N (Neutral) for at least one minute after every
STARTING AND OPERATING 261
5

Driving In Snow, Mud and Sand
In heavy snow, when pulling a load, or for additional
control at slower speeds, shift the transmission to a low
gear and shift the transfer case to 4WD LOW if necessary.
Refer to “Four-Wheel Drive Operation” in this section.
Do not shift to a lower gear than necessary to maintain
headway. Over-revving the engine can spin the wheels
and traction will be lost.
Avoid abrupt downshifts on icy or slippery roads, be-
cause engine braking may cause skidding and loss of
control.
Hill Climbing
NOTE:Before attempting to climb a hill, determine the
conditions at the crest and/or on the other side.
Before climbing a steep hill,shift the transmission to a
lower gear and shift the transfer case to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.If you stall or begin to lose headwaywhile climbing a
steep hill, allow your vehicle to come to a stop and
immediately apply the brakes. Restart the engine and
shift to R (Reverse). Back slowly down the hill allowing
the compression braking of the engine to help regulate
your speed. If the brakes are required to control vehicle
speed, apply them lightly and avoid locking or skidding
the tires.
WARNING!
If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle. Always back care-
fully straight down a hill in R (Reverse) gear. Never
back down a hill in N (Neutral) using only the brake.
270 STARTING AND OPERATING

•After extended operation in mud, sand, water, or
similar dirty conditions, have brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
WARNING!
Abrasive material in any part of the brakes may
cause excessive wear or unpredictable braking. You
might not have full braking power when you need it
to prevent an accident. If you have been operating
your vehicle in dirty conditions, get your brakes
checked and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
PARKING BRAKE
To set the parking brake, pull the lever up as firmly as
possible. When the parking brake is applied with the
ignition ON, the “Brake Warning Light” in the instru-
ment cluster will light. To release the parking brake, pull
up slightly, press the center button, then lower the lever
completely.
NOTE:The instrument cluster “Brake Warning Light”
indicates only that the parking brake is applied. It does
not indicate the degree of brake application.
272 STARTING AND OPERATING

When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type and tires must be properly inflated to produce
accurate signals for the computer.
WARNING!
Significant over or under inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low-speed self-
test at about 12 mph (20 km/h). If you have your foot
lightly on the brake while this test is occurring you may
feel slight pedal movement. The movement can be more
apparent on ice and snow. This is normal.
The Anti-Lock Brake System pump motor runs during
the self-test at 12 mph (20 km/h) and during an ABS stop.
The pump motor makes a low humming noise during
operation, which is normal.
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CAUTION!
Prolonged operation of the steering system at the
end of the steering wheel travel will increase the
steering fluid temperature and it should be avoided
when possible. Damage to the power steering pump
may occur.
MULTI DISPLACEMENT SYSTEM (MDS) - 5.7L
Engine Only
This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.
NOTE:The MDS system may take some time to return
to full functionality after a battery disconnect.
TIRE SAFETY INFORMATION
Tire Markings
NOTE:
•P (Passenger)-Metric tire sizing is based on U.S. design
standards. P-Metric tires have the letter “P” molded
into the sidewall preceding the size designation. Ex-
ample: P215/65R15 95H.
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