2009 JEEP COMMANDER check engine light

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 authorized 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 drivability. 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
418 MAINTAINING YOUR VEHICLE

manual). Tighten the gas cap until aclickingsound is
heard. This is an indication that the gas cap is properly
tightened.
The message will remain displayed until the vehicle
diagnostic 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 damaged
cap. 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 that require an Inspection and Mainte-
nance (I/M), this check verifies the Malfunction
Indicator Light (MIL) is functioning and is not on
when the engine is running, and that the OBD II system
is ready for testing.
Normally, the OBD II system will be ready. The OBD II
system maynotbe ready if your vehicle was recently
serviced, recently had a dead battery or a battery replace-
ment. If the OBD II system should be determined not
ready for the I/M test, your vehicle may fail the test.
MAINTAINING YOUR VEHICLE 419
7

Windshield Wiper Blades
Clean the rubber edges of the wiper blades and the
windshield periodically with a sponge or soft cloth and a
mild nonabrasive cleaner to remove accumulations of salt
or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.
Avoid using the wiper blades to wipe frost or ice from the
windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Adding Washer Fluid
On vehicles equipped with a Electronic Vehicle Informa-
tion Center (EVIC), the low washer fluid level will be
indicated. When the sensor detects a low fluid level, the
windshield will light on the vehicle graphic outline and
the “WASHER FLUID LOW” message will be displayed.The fluid reservoir for the windshield washers and the
rear window washer is shared. The fluid reservoir is
located in the engine compartment, be sure to check the
fluid level at regular intervals. Fill the reservoir with
windshield washer solvent only (not radiator antifreeze).
When refilling the washer fluid reservoir, take some
washer fluid and apply it to a cloth or towel and wipe
clean the wiper blades, this will help blade performance.
To prevent freeze-up of your windshield washer system
in cold weather, select a solution or mixture that meets or
exceeds the temperature range of your climate. This
rating information can be found on most washer fluid
containers.
428 MAINTAINING YOUR VEHICLE

•Change your engine oil more often if you drive your
vehicle off-road for an extended period of time.
•Under no circumstances should oil change intervals
exceed 6,000 miles (10,000 km) or 6 months, whichever
comes first.
Your authorized dealer will reset the oil change indicator
message after completing the scheduled oil change. If this
scheduled oil change is performed by someone other
than your authorized dealer the message can be reset by
referring to the steps described under ”Electronic Vehicle
Information Center” in Section 4 of this manual.
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 while
the 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 and add if
required.
Once a Month
•Check 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 coolant reservoir, brake
master cylinder, power steering and transmission
(4.7L and 5.7L engines) and add as needed.
•Check all lights and other electrical items for correct
operation.
At Each Oil Change
•Change the engine oil filter.
•Inspect the brake hoses and lines.
MAINTENANCE SCHEDULES 471
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ABS (Anti-Lock Brake System).............. 320
Adding Fuel........................... 375
Adjustable Pedals....................... 152
Air Cleaner, Engine (Engine Air Cleaner Filter) . . . 424
Air Conditioner Maintenance............... 426
Air Conditioning........................ 274
Air Conditioning, Operating Tips............ 283
Air Conditioning, Rear Zone................ 281
Air Conditioning Refrigerant............... 427
Air Conditioning System.................. 274
Air Filter.............................. 424
Air Pressure, Tires....................... 347
Airbag................................ 52
Airbag Deployment....................... 59
Airbag Light.......................61,75,193
Airbag Maintenance....................... 61
Alarm, Panic............................ 24
Alarm (Security Alarm).................20,194
Alterations/Modifications, Vehicle............. 9Antenna, Satellite Radio................... 264
Antifreeze (Engine Coolant)................ 465
Anti-Lock Brake System (ABS)............320,323
Anti-Lock Warning Light.................. 193
Anti-Theft System....................... 194
Appearance Care........................ 444
Arming Theft System (Security Alarm)......... 20
Assist, Hill Start........................ 332
Assistance Towing....................... 102
Auto Down Power Windows................ 35
Automatic Dimming Mirror................. 84
Automatic Door Locks..................... 30
Automatic Headlights.................... 141
Automatic Temperature Control (ATC)......... 274
Automatic Transmission................299,440
Adding Fluid......................... 442
Fluid and Filter Changes................. 440
Fluid Level Check..................... 441
Fluid Type........................... 440
496 INDEX

Cargo Load Floor........................ 178
Cargo (Vehicle Loading)................... 378
Cellular Phone........................88,270
Center High Mounted Stop Light............ 464
Certification Label....................... 378
Chains, Tire............................ 354
Changing A Flat Tire..................... 401
Chart, Tire Sizing........................ 339
Check Engine Light
(Malfunction Indicator Light)............... 419
Checks, Safety........................... 75
Child Restraint....................64,65,69,71
Child Restraint Tether Anchors.............68,69
Child Safety Locks........................ 33
Climate Control......................... 271
Clock........................220,234,237,247
Cold Weather Operation................... 294
Command View Skylights.................. 172
Compact Disc (CD) Maintenance............. 270Compact Spare Tire...................... 349
Compass.............................. 210
Compass Calibration..................... 210
Compass Variance....................... 211
Computer, Trip/Travel.................... 206
Connector
UCI ................................ 257
Universal Consumer Interface (UCI)......... 257
Console, Overhead....................... 162
Contract, Service........................ 489
Cooling System......................... 431
Adding Coolant (Antifreeze).............. 433
Coolant Capacity...................... 465
Coolant Level......................... 435
Disposal of Used Coolant................ 435
Drain, Flush, and Refill.................. 432
Inspection........................... 431
Points to Remember.................... 436
Pressure Cap......................... 434
498 INDEX

Engine Oil Viscosity Chart................. 423
Enhanced Accident Response Feature.......... 60
Entry System, Illuminated.................. 21
Event Data Recorder...................... 62
Exhaust Gas Caution..............42,74,371,429
Exhaust System......................... 429
Extender, Seat Belt........................ 52
Exterior Finish Care...................... 444
Fabric Care............................ 446
Filters
Air Cleaner.......................... 424
Engine Oil........................... 424
Engine Oil Disposal.................... 424
Finish Care............................ 444
Flashers.............................. 400
Hazard Warning....................... 400
Turn Signal.....................192,460,462Flexible Fuel Vehicles
Cruising Range....................... 374
Engine Oil........................... 374
Fuel Requirements..................372,373
Replacement Parts..................... 375
Starting............................. 374
Flipper Glass, Liftgate..................... 38
Flooded Engine Starting................... 295
Fluid Capacities......................... 465
Fluid Leaks............................. 76
Fluid Level Checks
Automatic Transmission..............440,441
Brake.............................. 437
Engine Oil........................... 422
Power Steering........................ 317
Fluids, Lubricants and Genuine Parts.......... 466
Fog Light Service........................ 461
Fog Lights.......................143,199,461
Fold and Tumble Rear Seat................. 128
INDEX 501
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Courtesy/Reading..................... 147
Cruise.............................. 198
Daytime Running...................... 143
Dimmer Switch, Headlight.............140,146
Electronic Stability Program (ESP) Indicator . . . 336
Electronic Throttle Control Warning......... 199
Fog ..........................143,199,461
Four-Wheel Drive Indicator............... 198
Fuses............................... 449
Hazard Warning Flasher................. 400
Headlight Switch...................... 140
Headlights........................... 458
Headlights On With Wipers............... 141
High Beam Indicator.................... 192
Illuminated Entry....................... 21
Instrument Cluster..................140,144
Interior..........................144,147
Lights On Reminder.................... 145
Low Fuel............................ 200Malfunction Indicator (Check Engine)........ 193
Oil Pressure.......................... 194
Passing............................. 146
Reading............................. 147
Rear Servicing........................ 462
Rear Tail............................ 462
Seat Belt Reminder..................... 198
Security Alarm (Theft Alarm).............. 194
Service............................. 458
Service Engine Soon (Malfunction Indicator) . . . 193
Side Marker.......................... 462
SmartBeams.......................... 141
Tire Pressure Monitoring (TPMS)........... 195
Tow/Haul Indicator.................... 197
Traction Control....................... 336
Turn Signal..................140,145,460,462
Vanity Mirror.......................... 87
Voltage............................. 199
Load Floor, Cargo....................... 178
INDEX 505
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