2008 JEEP PATRIOT check engine

13. Engine Coolant 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.
14. Brake System Warning Light
This light monitors various brake functions, in-
cluding brake fluid level and parking brake appli-
cation. If the brake light turns on, it may indicate that the
parking brake is applied, there is a low brake fluid level
or there is a problem with the Anti-Lock Brake System
(ABS).
The dual-brake system provides a reserve braking capac-
ity in the event of a failure to a portion of the hydraulic
system. Failure of either half of the dual-brake system is
indicated by the Brake Warning Light which will turn on
when the brake fluid level in the master cylinder has
dropped below a specified level.The light will remain on until the cause is corrected.
NOTE:The light may flash momentarily during sharp
cornering maneuvers which change fluid level condi-
tions. The vehicle should have service performed, and
the brake fluid level checked.
If brake failure is indicated, immediate repair is neces-
sary.
WARNING!
Driving a vehicle with the brake light on is danger-
ous. Part of the brake system may have failed. It will
take longer to stop the vehicle. You could have an
accident. Have the vehicle checked immediately.
UNDERSTANDING YOUR INSTRUMENT PANEL 175
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26. Malfunction Indicator Light (MIL)
This light is part of an Onboard Diagnostic
system called OBD II that monitors emissions,
engine, and automatic transmission control sys-
tems. The light will illuminate when the key is in the
ON/RUN position before engine start. If the light does
not come on when turning the key from OFF to ON/
RUN, have the condition checked promptly.
Certain conditions such as a loose or missing gas cap,
poor fuel quality, etc., may illuminate the light after
engine start. The vehicle should be serviced if the light
stays on through several of your typical driving cycles. In
most situations the vehicle will drive normally and will
not require towing.
If the MIL flashes when the engine is running, serious
conditions may exist 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.27. Hill Descent Indicator Light — If Equipped
The symbol illuminates (is armed) when the
4WD Lock switch is activated and the trans-
mission range indicator is in LOW or REVERSE
position (Off-Road Mode).
28. Front Fog Light Indicator Light — If Equipped
This light shows when the front fog lights are on.
29. Electronic Stability Program (ESP) Indicator
Light/Traction Control System (TCS) Indicator Light —
If Equipped
If this indicator light flashes during accelera-
tion, apply as little throttle as possible. While
driving, ease up on the accelerator. Adapt your
speed and driving to the prevailing road con-
ditions, and do not switch off the ESP, or TCS — if
equipped.
UNDERSTANDING YOUR INSTRUMENT PANEL 181
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30. Electronic Stability Program (ESP) Indicator Light
The malfunction light for the ESP is combined
with BAS. The yellow “ESP/BAS Warning
Light” comes on when the ignition switch is
turned to the ON position. They 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 remains on after several ignition
cycles, and the vehicle has been driven several miles/
kilometers at speeds greater than 30 mph (48 km/h), see
your authorized dealer as soon as possible.
31. 4WD! Warning Light
This light monitors the 4-Wheel Drive (4WD)
system. The light will come on, for a bulb
check, when the ignition key is turned to the
ON position and may stay on for as long as
three seconds.When lit solid:There is an 4WD system fault. 4WD
performance will be at a reduced level. Service the 4WD
system soon.
When blinking:The 4WD system is temporarily dis-
abled due to overload condition.
32. Electronic Vehicle Information Center Display — If
Equipped
When the appropriate conditions exist, this display
shows the Electronic Vehicle Information Center (EVIC)
messages.
33. Electronic Vehicle Information Center (EVIC)
Button — If Equipped
Pushing this button, will change the display to the
choices available for EVIC.
182 UNDERSTANDING YOUR INSTRUMENT PANEL

•Right Front Turn Signal Light Out (with a single
chime)
•Right Rear Turn Signal Light Out (with a single chime)
•RKE Battery Low (with a single chime)
•Personal Settings Not Available – Vehicle not in PARK
(automatic transmissions) or vehicle is in motion
(manual transmissions).
•Left/Right Front Door Ajar (one or more, with a single
chime if speed is above 1 mph (1 km/h)
•Left/Right Rear Door Ajar (one or more, with a single
chime if speed is above 1 mph (1 km/h)
•Door(s) Ajar (with a single chime if vehicle is in
motion)
•Gate Ajar (with a single chime)
•Headlights On
•Key In Ignition
•Check TPM System
Engine Oil Change Indicator System
Oil Change Required
Your vehicle is equipped with an engine oil change
indicator system. The “Oil Change Required” message
will flash in the EVIC display for approximately 10
seconds after a single chime has sounded, to indicate the
next scheduled oil change interval. The engine oil change
indicator system is duty-cycle based, which means the
engine oil change interval may fluctuate dependent upon
your personal driving style.
Unless reset, this message will continue to display each
time you turn the ignition switch to the ON/RUN
position. To turn off the message temporarily, press and
release the Trip Odometer button on the instrument
184 UNDERSTANDING YOUR INSTRUMENT PANEL

Towing Tips — Automatic Transmission
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 the “Main-
tenance Schedule” in Section 8 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 the potential for engine and transmission
overheating, take the following actions:
City Driving
When stopped for short periods of time, put transmission
in NEUTRAL but do not increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
refer to Cooling System Operating information in the
Maintenance section of this manual for more informa-
tion.
328 STARTING AND OPERATING

MAINTAINING YOUR VEHICLE
CONTENTS

Engine Compartment — Gasoline...........348

Onboard Diagnostic System — OBD II........349
▫Loose Fuel Filler Cap Message............349

Emissions Inspection And Maintenance
Programs............................350

Replacement Parts......................351

Authorized Dealer Service................352

Maintenance Procedures..................352
▫Engine Oil..........................352▫Drive Belt — Check Condition............356
▫Spark Plugs.........................356
▫Catalytic Converter....................356
▫Crankcase Emission Control System........358
▫Fuel Filter..........................358
▫Air Cleaner Element (Filter)..............358
▫Maintenance-Free Battery................359
▫Air Conditioner Maintenance.............361
▫Power Steering — Fluid Check............362
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RESET button to turn off the message. 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 MIL. Resolving the problem will turn the MIL
light off.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of this 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 the 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, the vehicle may fail the test.
This vehicle has a simple ignition key-actuated test,
which you can use prior to going to the test station. To
check if this vehicle’s OBD II system is ready, you must
do the following:
1. Insert the ignition key into the ignition switch.
2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn the ignition key to the ON
position, you will see the MIL symbol come on as part of
a normal bulb check.
350 MAINTAINING YOUR VEHICLE

5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn OFF
the ignition key or start the engine. This means that the
vehicle’s OBD II system isnot readyand you should
notproceed to the I/M station.
b. The MIL will not flash at all and will remain fully
illuminated until you turn OFF the ignition key or start
the engine. This means that the vehicle’s OBD II
system isready,and you can proceed to the I/M
station.
If the OBD II system isnot ready,you should see an
authorized dealer or repair facility. If this vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive the vehicleas you normally would in order for the OBD II system to
update. A recheck with the above test routine may then
indicate that the system is now ready.
Regardless of whether the vehicle’s OBD II system is
ready or not ready, if the MIL is illuminated during
normal vehicle operation, you should have the vehicle
serviced before going to the I/M station. The I/M station
can fail the vehicle because the MIL is on with the engine
running.
REPLACEMENT PARTS
The use of genuine Moparparts for normal/scheduled
maintenance and repairs is highly recommended to en-
sure the designed performance. Damage or failures
caused by the use of non-Moparparts for maintenance
and repairs will not be covered by the manufacturer’s
warranty.
MAINTAINING YOUR VEHICLE 351
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