check engine light JEEP WRANGLER 2010 JK / 3.G Owners Manual

NOTE:If you turned the wheel to the right to engage
the lock, you must turn the wheel slightly to the right to
disengage it. If you turned the wheel to the left to engage
the lock, turn the wheel slightly to the left to disengage it.
SENTRY KEY
The Sentry Key Immobilizer System prevents unautho-
rized vehicle operation by disabling the engine. The
system does not need to be armed or activated. Operation
is automatic, regardless of whether the vehicle is locked
or unlocked.
The system uses ignition keys that have an embedded
electronic chip (transponder) to prevent unauthorized
vehicle operation. Therefore, only keys that are pro-
grammed to the vehicle can be used to start and operate
the vehicle. The system will shut the engine off in two
seconds if someone uses an invalid key to try to start the
engine. NOTE:
A key that has not been programmed is also
considered an invalid key, even if it is cut to fit the
ignition switch lock cylinder for that vehicle.
During normal operation, after turning on the ignition
switch, the Vehicle Security Light will turn on for three
seconds for a bulb check. If the light remains on after the
bulb check, it indicates that there is a problem with the
electronics. In addition, if the Vehicle Security Light
begins to flash after the bulb check, it indicates that
someone used an invalid key to try to start the engine.
Either of these conditions will result in the engine being
shut off after two seconds.
If the Vehicle Security Light turns on during normal
vehicle operation (vehicle running for longer than 10 sec-
onds), it indicates that there is a fault in the electronics.
Should this occur, have the vehicle serviced as soon as
possible by an authorized dealer.
14 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

WARNING! (Continued)
Failure to properly follow floor mat installation or
mounting can cause interference with the brake
pedal and accelerator pedal operation causing loss of
control of the vehicle.
Periodic Safety Checks You Should Make Outside
the Vehicle
Tires
Examine tires for excessive tread wear and uneven wear
patterns. Check for stones, nails, glass, or other objects
lodged in the tread. Inspect the tread and sidewall for
cuts and cracks. Check the wheel nuts for tightness.
Check the tires (including spare) for proper pressure.
Lights
Have someone observe the operation of exterior lights
while you work the controls. Check turn signal and high
beam indicator lights on the instrument panel.
Door Latches
Check for positive closing, latching, and locking.
Fluid Leaks
Check area under vehicle after overnight parking for fuel,
engine coolant, oil, or other fluid leaks. Also, if gasoline
fumes are detected or if fuel, power steering fluid, or
brake fluid leaks are suspected, the cause should be
located and corrected immediately.
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THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 79

INSTRUMENT CLUSTER DESCRIPTIONS
1. Fuel Gauge
The pointer shows the level of fuel in the fuel tank.
NOTE:When the ignition switch is turned to OFF, the
fuel gauge and temperature gauge may not show accu-
rate readings. When the engine is not running, turn the
ignition switch to ON to obtain accurate readings.
2. Charging System Light This light shows the status of the electrical charg-
ing system. The light should come on when the
ignition switch is first turned ON, and remain on briefly
as a bulb check. If the light stays on or comes on while
driving, turn off some of the vehicle’s non-essential
electrical devices or increase engine speed (if at idle). If
the charging system light remains on, it means that the
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”.
3. Front Fog Light Indicator — If Equipped
This indicator will illuminate when the front fog
lights are on.
4. Low Fuel Warning Light When the fuel level reaches approximately 2.8 gal
(10.6L) this light will turn on and a single chime
will sound.
5. Speedometer
Indicates vehicle speed.
6. Front Axle Lock Indicator — If Equipped Indicates when the front axle lock has been
activated.
246 UNDERSTANDING YOUR INSTRUMENT PANEL

7. Seat Belt Reminder LightA warning chime and an indicator light will alert
you to buckle the seat belts. When the belt is
buckled, the chime will stop, but the light will stay
on for about six seconds, until it times out. Refer to
“Occupant Restraints” in “Things To Know Before Start-
ing Your Vehicle” for further information.
8. Turn Signal Indicators The arrows will flash with the exterior turn signals
when the turn signal lever is operated. A tone will
chime if the turn signals are left on for more than 1 mile
(1.6 km).
9. Oil Pressure Warning Light This light indicates low engine oil pressure. The
light should turn on momentarily when the engine
is started, if the bulb does not come on, have the system
checked by an authorized dealer. If the light turns on while driving, stop the vehicle and shut off the engine as
soon as possible. A chime will sound when this light
turns on.
Do not operate the vehicle until the cause is corrected.
This light does not indicate how much oil is in the engine.
The engine oil level must be checked under the hood.
10. High Beam Indicator
This indicator shows that the high beam head-
lights are on. Push the multifunction control lever
away from you to switch the headlights to high beam.
Pull the lever towards you to switch the headlights back
to low beam. If the driver’s door is open, and the
headlights or park lights are left on, the high beam
indicator light will remain illuminated and a chime will
sound.
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UNDERSTANDING YOUR INSTRUMENT PANEL 247

13. Airbag Warning LightThis light will turn on for four to eight seconds
as a bulb check when the ignition switch is first
turned ON. If the light is either not on during
starting, stays on, or turns on while driving,
then have the system inspected at an authorized dealer as
soon as possible. Refer to “Occupant Restraints” in
“Things To Know Before Starting Your Vehicle” for
further information.
14. Rear Axle Lock Indicator — If Equipped This light indicates when the rear axle lock has
been activated.
15. Tachometer
Indicates the engine speed in revolutions per minute
(RPM).CAUTION!
Do not operate the engine with the tachometer
pointer in the red area. Engine damage will occur.
16. Engine Temperature Warning Light This light warns of an overheated engine condi-
tion. If the engine is critically hot, a warning chime
will sound 10 times. After the chime turns off, the
engine will still be critically hot until the light goes out.
17. Vehicle Security Light — If Equipped This light will flash at a fast rate for approxi-
mately 15 seconds, when the vehicle security
alarm is arming, and then will flash slowly
until the vehicle is disarmed.
250 UNDERSTANDING YOUR INSTRUMENT PANEL

1. Turn the ignition switch to the ON position (Do not
start the engine).
2. Fully depress the accelerator pedal slowly three
times within 10 seconds.
3. Turn the ignition switch to the OFF/LOCK position.
NOTE: If the indicator message illuminates when you
start the vehicle, the oil change indicator system did not
reset. If necessary repeat this procedure.
25. Malfunction Indicator Light (MIL) The Malfunction Indicator Light (MIL) is a part of
an Onboard Diagnostic System called OBD II that
monitors engine and automatic transmission con-
trol systems. The light will illuminate when the ignition
is in the ON position, before engine start. If the bulb does
not come on when turning the key from OFF to ON, have
the condition checked promptly. Certain conditions such as a loose or missing gas cap,
poor quality fuel, etc. may illuminate the light after
engine start. The vehicle should be serviced if the light
stays on through several typical driving styles. In most
situations, the vehicle will drive normally and will not
require towing.
When the engine is running, the MIL may flash to alert
serious conditions that could lead to immediate loss of
power or severe catalytic converter damage. The vehicle
should be serviced as soon as possible if this occurs.
CAUTION!
Prolonged driving with the MIL on could cause
damage to the engine control system. It also could
affect fuel economy and drivability. If the MIL is
flashing, severe catalytic converter damage and
power loss will soon occur. Immediate service is
required.
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UNDERSTANDING YOUR INSTRUMENT PANEL 257

WARNING!
The Electronic Stability Control (ESC) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions. ESC cannot prevent acci-
dents, including those resulting from excessive speed
in turns, driving on very slippery surfaces, or hydro-
planing. Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of an ESC-
equipped vehicle must never be exploited in a reck-
less or dangerous manner which could jeopardize the
user’s safety or the safety of others.
27. O/D (Overdrive) Off Indicator Light This light will illuminate when the O/D OFF
button has been selected and overdrive has been
turned off. The O/D OFF button is located on the center
console. 28. Sway Bar Indicator Light — If Equipped
This indicator will illuminate when the front
sway bar is disconnected.
29. Electronic Stability Program (ESP) / Brake Assist
System (BAS) Warning Light The Electronic Stability Program (ESP) / Brake
Assist System (BAS) warning light in the in-
strument cluster comes on when the ignition
switch is turned to the ON position. The light
should go out with the engine running. If the ESP/BAS
warning light comes on continuously with the engine
running, a malfunction has been detected in either the
ESP or the BAS system. If this light stays illuminated,
have the ESP and BAS checked at an authorized dealer as
soon as possible. Refer to “Electronic Brake Control
System” in “Starting And Operating” for further infor-
mation.
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UNDERSTANDING YOUR INSTRUMENT PANEL 259

WARNING!
If a warning light remains on the system may not be
working and you will not have the benefit of ESP or
BAS. Under certain driving conditions, where ESP or
BAS would be beneficial, you - if you have not
adjusted your driving speeds and stopping in or to
account for the lack of the feature, may be in acci-
dent.
30. Electronic Throttle Control (ETC) Light This light informs you of a problem with the
Electronic Throttle Control (ETC) system. If a
problem is detected while the engine is run-
ning, the light will either stay on or flash
depending on the nature of the problem. Cycle the
ignition key when the vehicle is safely and completely
stopped and the shift lever is placed in the PARK
position. The light should turn off. If the light remains on with the engine running, your vehicle will usually be
drivable; however, see an authorized dealer for service as
soon as possible.
If the light continues to flash 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. 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 autho-
rized dealer.
31. Compass / Mini-Trip Computer Display — If
Equipped
When the appropriate conditions exist, this display
shows the Mini-Trip Computer messages. Refer to “Mini-
Trip Computer”.
260 UNDERSTANDING YOUR INSTRUMENT PANEL

The following procedure will disable (or re-enable) ESP
functionality in the vehicle:
1. Shift the transfer case into the 4H range position.
2. Turn the steering wheel until it is centered and the
wheels are pointed straight ahead.
3. Cycle the ignition key OFF to ON.
4. Wait approximately five seconds for the system bulb
check.
5. Turn and hold the steering wheel one-half turn to the
right (clockwise).
6. Press and hold the ESP OFF button for seven seconds.
7. Turn the steering wheel back to center, and turn and
hold an additional one-half turn to the left (counterclock-
wise).
8. Press and hold the ESP OFF button for seven seconds.9. Turn the steering wheel back to center.
10. Press and hold the ESP OFF button for seven seconds.
11. Cycle the ignition key to OFF.
After performing the ESP disable procedure correctly,
“ESP OFF” will be displayed in the odometer for approxi-
mately 12 seconds each time the ignition is moved to ON.
Repeating the ESP disable procedure will re-enable nor-
mal ESP operation.
ESP/BAS Warning Light
The malfunction indicator lamp for the ESP is
combined with the BAS indicator. The “ESP/
BAS Warning Light” in the instrument cluster
comes on when the ignition switch is turned to
the “ON” position. It should go out with the engine
running.
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STARTING AND OPERATING 385

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” for the proper maintenance intervals.
NOTE:Check the automatic transmission fluid level
before towing.
O/D Off
To reduce the potential for automatic transmission over-
heating, select the “O/D OFF” feature when driving in
hilly areas or shift the transmission to DRIVE position 2
on more severe grades. Refer to “Automatic Transmis-
sion” in “Starting and Operating” for further
information.
Electronic Speed Control – If Equipped

Do not 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.
Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
434 STARTING AND OPERATING