2018 JEEP GRAND CHEROKEE check engine light

If the light remains on when the parking
brake has been disengaged, and the fluid
level is at the full mark on the master cylinder
reservoir, it indicates a possible brake hy-
draulic system malfunction or that a problem
with the Brake Booster has been detected by
the Anti-Lock Brake System (ABS) / Elec-
tronic Stability Control (ESC) system. In this
case, the light will remain on until the condi-
tion has been corrected. If the problem is
related to the brake booster, the ABS pump
will run when applying the brake, and a brake
pedal pulsation may be felt during each stop.
The dual brake system provides a reserve
braking capacity in the event of a failure to a
portion of the hydraulic system. A leak in
either half of the dual brake system is indi-
cated by the Brake Warning Light, which will
turn on when the brake fluid level in the
master cylinder has dropped below a speci-
fied 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 conditions. The vehicle should have
service performed, and the brake fluid level
checked.
If brake failure is indicated, immediate repair
is necessary.
WARNING!
Driving a vehicle with the red brake light
on is dangerous. Part of the brake system
may have failed. It will take longer to stop
the vehicle. You could have a collision.
Have the vehicle checked immediately.
Vehicles equipped with the Anti-Lock Brake
System (ABS) are also equipped with Elec-
tronic Brake Force Distribution (EBD). In the
event of an EBD failure, the Brake Warning
Light will turn on along with the ABS Light.
Immediate repair to the ABS system is re-
quired.
Operation of the Brake Warning Light can be
checked by turning the ignition switch from
the OFF position to the ON/RUN position.The light should illuminate for approximately
four seconds. The light should then turn off
unless the parking brake is applied or a brake
fault is detected. If the light does not illumi-
nate, have the light inspected by an autho-
rized dealer.
The light also will turn on when the parking
brake is applied with the ignition switch in
the ON/RUN position.
NOTE:
This light shows only that the parking brake is
applied. It does not show the degree of brake
application.
— Battery Charge Warning Light
This light illuminates when the battery is not
charging properly. If it stays on while the
engine is running, there may be a malfunc-
tion with the charging system. Contact your
authorized dealer as soon as possible.
This indicates a possible problem with the
electrical system or a related component.
— Door Open Warning Light
This indicator will illuminate when a door is
ajar/open and not fully closed.
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NOTE:
If the vehicle is moving, there will also be a
single chime.
— Electric Power Steering Fault
Warning Light
This light will turn on when there's a fault
with the EPS (Electric Power Steering) sys-
tem. Refer to “Power Steering” in “Starting
And Operating” in the Owner’s Manual for
further information.
WARNING!
Continued operation with reduced assist
could pose a safety risk to yourself and
others. Service should be obtained as soon
as possible.
— Electronic Throttle Control (ETC)
Warning Light
This light informs you of a problem with the
Electronic Throttle Control (ETC) system. If a
problem is detected while the vehicle is run-
ning, the light will either stay on or flash
depending on the nature of the problem.Cycle the ignition when the vehicle is safely
and completely stopped and the transmission
is placed in the PARK position. The light
should turn off. If the light remains on with
the vehicle running, your vehicle will usually
be drivable; however, see an authorized
dealer for service as soon as possible.
NOTE:
This light may turn on if the accelerator and
brake pedals are pressed at the same time.
If the light continues to flash when the ve-
hicle is running, immediate service is re-
quired and you may experience reduced per-
formance, an elevated/rough idle, or engine
stall and your vehicle may require towing.
The light will come on when the ignition is
placed in the ON/RUN or ACC/ON/RUN posi-
tion 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.
— Engine Coolant Temperature Warn-
ing Light
This light warns of an overheated engine
condition. If the engine coolant temperature
is too high, this indicator will illuminate and
a single chime will sound. If the temperature
reaches the upper limit, a continuous chime
will be sound for four minutes or until the
engine is able to cool: whichever comes first.
If the light turns on while driving, safely pull
over and stop the vehicle. If the A/C system is
on, turn it off. Also, shift the transmission
into NEUTRAL and idle the vehicle. If the
temperature reading does not return to nor-
mal, turn the engine off immediately and call
for service. Refer to “If Your Engine Over-
heats” in “In Case Of Emergency” for further
information.
— Hood Open Warning Light
This indicator will illuminate when the hood
is ajar/open and not fully closed.
NOTE:
If the vehicle is moving, there will also be a
single chime.
GETTING TO KNOW YOUR INSTRUMENT PANEL
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— Liftgate Open Warning Light
This indicator light will illuminate when the
liftgate is open.
NOTE:
If the vehicle is moving, there will also be a
single chime.
— Oil Pressure Warning Light
This warning light will illuminate to indicate
low engine oil pressure. 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.
— Oil Temperature Warning Light
This telltale indicates engine oil temperature
is high. If the light turns on while driving,
stop the vehicle and shut off the engine as
soon as possible. Wait for oil temperature to
return to normal levels.
— Seat Belt Reminder Warning Light
This light indicates when the driver or pas-
senger seat belt is unbuckled. When the
ignition is first placed in the ON/RUN or
ACC/ON/RUN position and if the driver’s seat
belt is unbuckled, a chime will sound and the
light will turn on. When driving, if the driver
or front passenger seat belt remains unbuck-
led, the Seat Belt Reminder Light will flash or
remain on continuously and a chime will
sound. Refer to “Occupant Restraint Sys-
tems” in “Safety” for further information.
— Transmission Temperature Warning
Light — If Equipped
This light indicates high transmission fluid
temperature. This may occur with strenuous
usage such as trailer towing. If this light turns
on, stop the vehicle and run the engine at idle
or slightly faster, with the transmission in
PARK or NEUTRAL, until the light turns off.
Once the light turns off, you may continue to
drive normally.
WARNING!
If you continue operating the vehicle when
the Transmission Temperature Warning
Light is illuminated you could cause the
fluid to boil over, come in contact with hot
engine or exhaust components and cause a
fire.
CAUTION!
Continuous driving with the Transmission
Temperature Warning Light illuminated
will eventually cause severe transmission
damage or transmission failure.
— Vehicle Security Warning 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.
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— LaneSense Warning Light — If
Equipped
The LaneSense Warning Light will be solid
yellow when the vehicle is approaching a lane
marker. The warning light will flash when the
vehicle is crossing the lane marker.
Refer to “LaneSense — If Equipped" in
“Starting And Operating” for further informa-
tion.
— Low Fuel Warning Light
When the fuel level reaches approximately
2.4 gal (9.1 L) this light will turn on, and
remain on until fuel is added.
A single warning chime will sound with Low
Fuel Warning.
— Low Washer Fluid Warning Light —
If Equipped
This indicator will illuminate when the wind-
shield washer fluid is low.
— Engine Check/Malfunction Indica-
tor Warning Light (MIL)
The Engine Check/Malfunction Indicator
Light (MIL) is a part of an Onboard Diagnostic
System called OBD II that monitors engine
and automatic transmission control systems.
This warning light will illuminate when the
ignition is in the ON/RUN position before
engine start. If the bulb does not come on
when turning the ignition switch from OFF to
ON/RUN, have the condition checked
promptly.
Certain conditions, such as a loose or missing
gas cap, poor quality fuel, etc., may illumi-
nate 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.
WARNING!
A malfunctioning catalytic converter, as
referenced above, can reach higher tem-
peratures than in normal operating condi-
tions. This can cause a fire if you drive
slowly or park over flammable substances
such as dry plants, wood, cardboard, etc.
This could result in death or serious injury
to the driver, occupants or others.
CAUTION!
Prolonged driving with the Malfunction
Indicator Light (MIL) on could cause dam-
age to the vehicle control system. It also
could affect fuel economy and driveability.
If the MIL is flashing, severe catalytic
converter damage and power loss will soon
occur. Immediate service is required.
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Your vehicle may also be designed to perform
any of these other functions in response to
the Enhanced Accident Response System:
• Turn off the Fuel Filter Heater, Turn off the
HVAC Blower Motor, Close the HVAC Circu-
lation Door
• Cut off battery power to the:
– Engine
– Electric Motor (if equipped)
– Electric power steering
– Brake booster
– Electric park brake
– Automatic transmission gear selector
– Horn
– Front wiper
– Headlamp washer pumpNOTE:
After an accident, remember to cycle the
ignition to the STOP (OFF/LOCK) position
and remove the key from the ignition switch
to avoid draining the battery. Carefully check
the vehicle for fuel leaks in the engine com-
partment and on the ground near the engine
compartment and fuel tank before resetting
the system and starting the engine. If there
are no fuel leaks or damage to the vehicle
electrical devices (e.g. headlights) after an
accident, reset the system by following the
procedure described below.
Enhanced Accident Response System Reset
Procedure
In order to reset the Enhanced Accident Re-
sponse System functions after an event, the
ignition switch must be changed from igni-
tion START or ON/RUN to ignition OFF. Care-
fully check the vehicle for fuel leaks in the
engine compartment and on the ground near
the engine compartment and fuel tank before
resetting the system and starting the engine.
Maintaining Your Air Bag System
WARNING!
• Modifications to any part of the air bag
system could cause it to fail when you
need it. You could be injured if the air
bag system is not there to protect you.
Do not modify the components or wiring,
including adding any kind of badges or
stickers to the steering wheel hub trim
cover or the upper right side of the in-
strument panel. Do not modify the front
bumper, vehicle body structure, or add
aftermarket side steps or running
boards.
• It is dangerous to try to repair any part of
the air bag system yourself. Be sure to
tell anyone who works on your vehicle
that it has an air bag system.
• Do not attempt to modify any part of your
air bag system. The air bag may inflate
accidentally or may not function prop-
erly if modifications are made. Take your
vehicle to an authorized dealer for any
air bag system service. If your seat, in-
cluding your trim cover and cushion,
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Front seat belt assemblies must be replaced
after a collision. Rear seat belt assemblies
must be replaced after a collision if they have
been damaged (i.e., bent retractor, torn web-
bing, etc.). If there is any question regarding
seat belt or retractor condition, replace the
seat belt.
Air Bag Warning Light
The Air Bag warning lightwill turn on for
four to eight seconds as a bulb check when
the ignition switch is first turned to ON/RUN.
If the light is either not on during starting,
stays on, or turns on while driving, have the
system inspected at your authorized dealer as
soon as possible. After the bulb check, this
light will illuminate with a single chime when
a fault with the Air Bag System has been
detected. It will stay on until the fault is
removed. If the light comes on intermittently
or remains on while driving, have your autho-
rized dealer service the vehicle immediately.
Refer to “Occupant Restraint Systems” in
“Safety” for further information.
Defroster
Check operation by selecting the defrost
mode and place the blower control on high
speed. You should be able to feel the air
directed against the windshield. See your
authorized dealer for service if your defroster
is inoperable.
Floor Mat Safety Information
Always use floor mats designed to fit your
vehicle. Only use a floor mat that does not
interfere with the operation of the accelera-
tor, brake or clutch pedals. Only use a floor
mat that is securely attached using the floor
mat fasteners so it cannot slip out of position
and interfere with the accelerator, brake or
clutch pedals or impair safe operation of your
vehicle in other ways.
WARNING!
An improperly attached, damaged, folded,
or stacked floor mat, or damaged floor mat
fasteners may cause your floor mat to
interfere with the accelerator, brake, or
clutch pedals and cause a loss of vehicle
WARNING!
control. To prevent SERIOUS INJURY or
DEATH:
• ALWAYS securely attach
your floor
mat using the floor mat fasteners. DO
NOT install your floor mat upside down
or turn your floor mat over. Lightly pull to
confirm mat is secured using the floor
mat fasteners on a regular basis.
• ALWAYS REMOVE THE EXISTING
FLOOR MAT FROM THE VEHICLE
before installing any other floor mat.
NEVER install or stack an additional
floor mat on top of an existing floor mat.
• ONLY install floor mats designed to fit
your vehicle. NEVER install a floor mat
that cannot be properly attached and
secured to your vehicle. If a floor mat
needs to be replaced, only use a FCA
approved floor mat for the specific
make, model, and year of your vehicle.
• ONLY use the driver’s side floor mat on
the driver’s side floor area. To check for
interference, with the vehicle properly
parked with the engine off, fully depress
the accelerator, the brake, and the
SAFETY
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Automatic Transmission
Start the engine with the transmission gear
selector in the PARK position. Apply the
brake before shifting to any driving range.
Normal Starting
Observe the instrument panel cluster lights
when starting the engine.
NOTE:
Normal starting of either a cold or a warm
engine is obtained without pumping or press-
ing the accelerator pedal
1. Always apply the parking brake.
2. Press and hold the brake pedal while
pushing the ENGINE START/STOP button
once.
NOTE:
A delay of the start of up to five seconds is
possible under very cold conditions. The
"Wait to Start" telltale will be illuminated
during the pre-heat process, When the
engine Wait To Start light goes off the
engine will automatically crank.
CAUTION!
If the “Water in Fuel Indicator Light” re-
mains on, DO NOT START engine before
you drain the water from the fuel filters to
avoid engine damage. Refer to “Draining
Fuel/Water Separator Filter” in “Servicing
And Maintenance” in your Diesel Supple-
ment for further information, which can be
found with your online Owner’s Informa-
tion.
3. The system will automatically engage the
starter to crank the engine. If the vehicle
fails to start, the starter will disengage
automatically after 25 seconds.
4. If you wish to stop the cranking of the
engine prior to the engine starting, push
the button again.
5. Check that the oil pressure warning light
has turned off.
6. Release the parking brake.
STOP/START SYSTEM — IF
EQUIPPED
The Stop/Start function is developed to re-
duce fuel consumption. The system will stop
the engine automatically during a vehicle
stop if the required conditions are met. Re-
leasing the brake pedal or pressing the accel-
erator pedal will automatically re-start the
engine.
This vehicle has been upgraded with a heavy
duty starter, enhanced battery, and other up-
graded engine parts, to handle the additional
engine starts.
Automatic Mode
The Stop/Start feature is enabled
after every normal customer en-
gine start. At that time, the sys-
tem will go into STOP/START
READY and if all other conditions are met,
can go into a STOP/START AUTOSTOP AC-
TIVE “Autostop” mode.
STARTING AND OPERATING
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display. Refer to “Instrument Cluster Dis-
play“ in “Getting to Know Your Instrument
Panel” for further information.
If the “SERVICE STOP/START SYSTEM”
message appears in the instrument cluster
display, have the system checked by an au-
thorized dealer.
ENGINE BREAK-IN
RECOMMENDATIONS
3.6L & 5.7L Engines
A long break-in period is not required for the
drivetrain (engine, transmission, clutch, and
rear axle) in your new vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles
(100 km), speeds up to 50 or 55 mph (80 or
90 km/h) are desirable.
While cruising, brief full-throttle acceleration
within the limits of local traffic laws contrib-
utes to a good break-in. However, wide-open
throttle acceleration in low gear can be det-
rimental and should be avoided.The engine oil, transmission fluid, and axle
lubricant installed at the factory is high-
quality and energy-conserving. Oil, fluid, and
lubricant changes should be consistent with
anticipated climate and conditions under
which vehicle operations will occur. For the
recommended viscosity and quality grades,
refer to “Fluids And Lubricants” in "Techni-
cal Specifications”.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.
NOTE:
A new engine may consume some oil during
its first few thousand miles (kilometers) of
operation. This should be considered a nor-
mal part of the break-in and not interpreted
as an indication of difficulty. Please check
your oil level with the engine oil indicator
often during the break in period. Add oil as
required.
Diesel Engine
The diesel engine does not require a break-in
period due to its construction. Normal opera-
tion is allowed, providing the following rec-
ommendations are followed:
• Warm up the engine before placing it under
load.
• Do not operate the engine at idle for pro-
longed periods.
• Use the appropriate transmission gear to
prevent engine lugging.
• Observe vehicle oil pressure and tempera-
ture indicators.
• Check the coolant and oil levels frequently.
• Vary throttle position at highway speeds
when carrying or towing significant weight.
NOTE:
Light duty operation such as light trailer tow-
ing or no load operation will extend the time
before the engine is at full efficiency. Re-
duced fuel economy and power may be seen
at this time.
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