2007 JEEP GRAND CHEROKEE check engine

is placed in the P (Park) position. The light should turn
off. If the light remains lit with the engine running your
vehicle will usually be drivable, however, see your dealer
for service as soon as possible. If the light is flashing
when the engine is running, immediate service is re-
quired and you may experience reduced performance, an
elevated/rough idle or engine stall and your vehicle may
require towing. 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.
24. Front Fog Light Indicator Light— If Equipped
This light shows the front fog lights are ON.
25. Voltage Warning Light
This light monitors the electrical system voltage.
The light should turn on momentarily as theengine is started. If the light stays on or turns on while
driving, it indicates a problem with the charging system.
Immediate service should be obtained.
26. Low Fuel Warning Light
When the fuel level reaches approximately 2.3 U.S.
Gallons (8.7 Liters) this light will come on and
remain on until fuel is added. The Low Fuel
Warning Light may turn on and off again, especially
during and after hard braking, accelerations, or turns.
This occurs due to the shifting of the fuel in the tank.
Also, a single chime will sound.
27. Glow Plug Indicator Light — Diesel Only
This light will illuminate when the ignition
switch is first turned to the ON position. Wait
until the light turns off before starting the
vehicle. Refer to “Starting Procedures” in Sec-
tion 5 of this manual.
182 UNDERSTANDING YOUR INSTRUMENT PANEL

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.
260 STARTING AND OPERATING

LOW Indicator Lamp” in the instrument cluster will
begin to flash and remain on solid when the shift is
complete. Release the T-handle.
NOTE:If shift conditions/interlocks are not met, or a
transfer case motor temperature protection condition
exists, a “CHECK SHIFT PROCEDURES” message will
flash from the EVIC (Electronic Vehicle Information Cen-
ter). Refer to “Electronic Vehicle Information Center
(EVIC)” in Section 4 of this manual. (See page 183 for
more information.)
4LOWto4HI
With the vehicle at speeds of 0 to 3 mph (0 to 5 km/h),
key ON or engine running, shift the transmission into N
(Neutral), and raise the transfer case T-handle. The “4WD
Shifter T-Handle
STARTING AND OPERATING 265
5

LOW Indicator Lamp” in the instrument cluster will flash
and go out when the shift is complete. Release the
T-handle.
NOTE:If shift conditions/interlocks are not met, or a
transfer case motor temperature protection condition
exists, a “CHECK SHIFT PROCEDURES” message will
flash from the EVIC (Electronic Vehicle Information Cen-
ter). Refer to “Electronic Vehicle Information Center
(EVIC)” in Section 4 of this manual. (See page 183 for
more information.)
NOTE:Shifting into or out of 4WD LOW is possible
with the vehicle completely stopped, however difficulty
may occur due to the mating clutch teeth not being
properly aligned. Several attempts may be required for
clutch teeth alignment and shift completion to occur. The
preferred method is with the vehicle rolling 0 to 3 mph (0
to 5 km/h). If the vehicle is moving faster than 3 mph (5
km/h), the transfer case will not allow the shift.Neutral (N) Shift Procedure
1. Key ON, engine off.
2. Vehicle stopped, with foot on brake.
3. Place transmission in N (Neutral).
4. Hold down N (Neutral) “pin” switch (with a pen, etc.)
for 4 seconds until the LED lamp by the switch starts to
blink indicating shift in progress. Lamp will stop blinking
(stay on solid) when Neutral shift is complete. A “4WD
SYSTEM IN NEUTRAL” message will display on the
EVIC (Electronic Vehicle Information Center). Refer to
“Electronic Vehicle Information Center (EVIC)” in Sec-
tion 4 of this manual. (See page 183 for more informa-
tion.)
266 STARTING AND OPERATING

CAUTION!
When driving through water, do not exceed 5 mph (8
km/h). Always check water depth before entering as
a precaution, and check all fluids afterward. Driving
through water may cause damage that may not be
covered by the new vehicle limited warranty.
Driving through water more than a few inches deep will
require extra caution to ensure safety and prevent dam-
age to your vehicle. If you must drive through water, try
to determine the depth and the bottom condition (and
location of any obstacles) prior to entering. Proceed with
caution and maintain a steady controlled speed less than
5 mph (8 km/h) in deep water to minimize wave effects.
Flowing Water
If the water is swift flowing and rising (as in storm
run-off) avoid crossing until the water level recedesand/or the flow rate is reduced. If you must cross
flowing water avoid depths in excess of 9 inches. The
flowing water can erode the streambed causing your
vehicle to sink into deeper water. Determine exit point(s)
that are downstream of your entry point to allow for
drifting.
Standing Water
Avoid driving in standing water deeper than 20 inches,
and reduce speed appropriately to minimize wave ef-
fects. Maximum speed in 20 inches of water is less than 5
mph (8 km/h).
Maintenance
After driving through deep water, inspect your vehicle
fluids and lubricants (engine oil, transmission oil, axle,
transfer case) to assure the fluids have not been contami-
nated. Contaminated fluid (milky, foamy in appearance)
should be flushed/changed as soon as possible to pre-
vent component damage.
STARTING AND OPERATING 269
5

Remember, never drive diagonally across a hill-always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain headway by
turning the front wheels slowly. This may provide a fresh
“bite” into the surface and will usually provide traction
to complete the climb.
Traction Downhill
Shift the transmission into a low gear and the transfer
case to 4WD LOW range. Let the vehicle go slowly down
the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
STARTING AND OPERATING 271
5

Towing Tips — Automatic Transmission
The “D” range can be selected when towing. However, if
frequent shifting occurs while in this range, the ”Tow/
Haul” mode (if equipped) or a lower gear range should
be selected.
NOTE:Using the ”Tow/Haul” mode (if equipped) or a
lower gear range while operating the vehicle under
heavy operating conditions will improve performance
and extend transmission life by reducing excessive shift-
ing and heat build up. This action will also provide better
engine braking.
The automatic transmission fluid and filter should be
changed if you REGULARLY tow a trailer for more than
45 minutes of continuous operation. Refer to “Mainte-
nance Schedule B” in Section 8 of this manual for
transmission fluid change intervals.
NOTE:Check the automatic transmission fluid level
before towing.
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.
STARTING AND OPERATING 331
5

MAINTAINING YOUR VEHICLE
CONTENTS

Engine Compartment – 3.7L...............354

Engine Compartment – 4.7L...............355

Engine Compartment – 5.7L...............356

Engine Compartment – 3.0L Diesel..........357

Onboard Diagnostic System — OBD II........358
▫Loose Fuel Filler Cap Message............358

Emissions Inspection And Maintenance
Programs............................359

Replacement Parts......................361
Dealer Service.........................361

Maintenance Procedures..................362
▫Engine Oil..........................362
▫Drive Belts — Check Condition And Tension . . 366
▫Spark Plugs.........................367
▫Spark Plug Wires.....................367
▫Engine Air Cleaner Filter................367
▫Catalytic Converter....................368
▫Crankcase Emission Control System........369
7