2007 JEEP GRAND CHEROKEE check engine light

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

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

ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light.” It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
•Prolonged driving with the “Malfunction Indica-
tor Light” on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per-
formed.
•If the “Malfunction Indicator Light” is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur.
Immediate service is required.
Loose Fuel Filler Cap Message
After fuel is added, the vehicle diagnostic system can
determine if the fuel filler cap is loose, improperly
installed, or damaged. A “CHECK GASCAP” message
will be displayed in the EVIC (Refer to Section 4 of this
358 MAINTAINING YOUR VEHICLE

manual). Tighten the gas cap until aclickingsound is
heard. This is an indication that the gas cap is properly
tightened.
This message may be temporarily overridden by pressing
either the C/T, STEP, or MENU buttons. However, after
one minute of no customer interaction, the EVIC will
display again the “CHECK GASCAP” message. The
message will remain displayed until the vehicle diagnos-
tic system can retest the fuel system. The test will
perform the next time the vehicle is started, if the vehicle
was keyed off above 40°F (4°C) outside temperature and
the following vehicle start is above 40°F (4°C) outside
temperature. It may be possible to have a message that
will not clear due to the test being disabled due to low
outside temperatures. If the test is performed and the
problem is gone, the message will disappear.
If the problem persists, the message will appear the next
time the vehicle is started. This might indicate a damagedcap. If the problem is detected twice in a row, the system
will turn on the Malfunction Indicator Light (MIL).
Resolving the problem will turn the MIL light off. See
your authorized dealer for service.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
MAINTAINING YOUR VEHICLE 359
7

Once a Month
•Check the tire pressure and look for unusual wear or
damage.
•Inspect the battery and clean and tighten the terminals
as required.
•Check the fluid levels of the coolant reservoir, brake
master cylinder, and transmission, and add as needed.
•Check all lights and all other electrical items for correct
operation.At Each Oil Change
•Change the engine oil filter.
•Inspect the exhaust system.
•Inspect brake hoses.
•Check the engine coolant/anti-freeze level, hoses, and
clamps.
•After completion of off-road operation, the underside
of the vehicle should be thoroughly inspected. Exam-
ine threaded fasteners for looseness.
414 MAINTENANCE SCHEDULES
8
M
A
I
N
T
E
N
A
N
C
E
S
C
H
E
D
U
L
E
S

NOTE:Most vehicles are operated under the conditions
listed for Schedule “B.”
Second is Schedule“A”. It is for vehicles that are not
operated under any of the conditions listed under Sched-
ule “B.”
Use the schedule that best describes your driving condi-
tions. Where time and mileage are listed, follow the
interval that occurs first.
CAUTION!
Failure to perform the required maintenance items
may result in damage to the vehicle.
At Each Stop for Fuel
•Check the engine oil level about 5 minutes after a fully
warmed engine is shut off. Checking the oil level whilethe vehicle is on level ground will improve the accu-
racy of the oil level reading. Add oil only when the
level is at or below the ADD or MIN mark.
•Check the windshield washer solvent, add as required.
Once a Month
•Check the tire pressure and look for unusual wear or
damage.
•Inspect the battery, clean and tighten the terminals as
required.
•Check the fluid levels of engine coolant/anti-freeze
deaeration bottle, brake master cylinder, and transmis-
sion, and add as needed.
•Check all lights and all other electrical items for correct
operation.
434 SCHEDULE “A”
8
M
A
I
N
T
E
N
A
N
C
E
S
C
H
E
D
U
L
E
S

ABS (Anti-Lock Brake System)............176,274
Adding Fuel........................... 313
Adding Washer Fluid..................... 165
Adjustable Pedals....................... 124
Air Cleaner, Engine (Engine Air Cleaner Filter) . . . 367
Air Conditioner Maintenance............... 371
Air Conditioning........................ 235
Air Conditioning, Operating Tips............ 242
Air Conditioning Refrigerant............... 372
Air Conditioning System.................. 235
AirFilter .............................. 367
Air Pressure, Tires....................... 288
Airbag................................ 43
Airbag Deployment....................... 50
Airbag Light....................... 52,66,176
Airbag Maintenance....................... 51
Alarm (Security Alarm)................. 18,177
Alarm System (Security Alarm)............... 18
Alignment and Balance................... 293Alterations/Modifications, Vehicle............. 9
Antenna, Satellite Radio................... 230
Antifreeze (Engine Coolant)................ 407
Anti-Lock Brake System (ABS)............129,274
Anti-Lock Warning Light.................. 176
Anti-Theft System..................... 18,177
Appearance Care........................ 389
Auto Down Power Windows................ 30
AutomaticDimmingMirror ................. 72
Automatic Door Locks..................... 27
Automatic Headlights..................... 114
Automatic Temperature Control (ATC)......... 236
Automatic Transmission................254,386
Adding Fluid......................... 387
Fluid and Filter Changes................. 386
Fluid Level Check...................... 386
FluidType ........................... 386
Special Additives...................... 388
Torque Converter...................... 260
452 INDEX

Filters
Air Cleaner.......................... 367
Engine Oil........................... 366
Engine Oil Disposal.................... 365
FinishCare ............................ 390
Flashers.............................. 338
Hazard Warning....................... 338
Turn Signal.....................175,403,404
Flexible Fuel Vehicles
Cruising Range........................ 311
Engine Oil........................... 311
Fuel Requirements..................309,310
Maintenance.......................... 312
Replacement Parts..................... 311
Starting............................. 311
Flipper Glass, Liftgate..................... 33
Flooded Engine Starting................... 249
Fluid Capacities......................... 407
Fluid Leaks............................. 66Fluid Level Checks
Automatic Transmission................. 386
Brake............................... 384
Engine Oil........................... 362
Power Steering........................ 372
Fluids, Lubricants and Genuine Parts.......... 408
Fog Light Service........................ 404
Fog Lights....................... 117,182,404
Folding Rear Seat........................ 104
Four Wheel Drive....................... 262
Operation........................... 262
Systems............................. 262
Four Wheel Drive Operation................ 262
Four-Way Hazard Flasher.................. 338
Freeing A Stuck Vehicle................... 261
FrontAxle(Differential) ................... 385
Fuel................................. 305
Filler Cap (Gas Cap).................... 313
Gasoline............................ 305
INDEX 457
10