2023 JEEP WRANGLER check engine

GETTING TO KNOW YOUR INSTRUMENT PANEL123
GREEN INDICATOR LIGHTS
Adaptive Cruise Control (ACC) Set With No
Target Detected Indicator Light —
If Equipped
This light will turn on when the Adaptive Cruise
Control is set and there is no vehicle in front
detected
Úpage 152.
Adaptive Cruise Control (ACC) Set With
Target Indicator Light — If Equipped
This will display when the ACC is set and a
vehicle in front is detected Úpage 152.
4WD Auto Indicator Light — If Equipped
This light alerts the driver that the vehicle is in
the Four-Wheel Drive auto mode. The system
will provide power to all four wheels and shift the power between the front and rear axles as needed.
This will provide maximum traction in dry and slippery
conditions.
Cruise Control SET Indicator Light —
If Equipped With A Premium Instrument
Cluster
This indicator light will illuminate when the
Cruise Control is set to the desired speed
Úpage 151.
Front Fog Indicator Light — If Equipped
This indicator light will illuminate when the
front fog lights are on Úpage 50.
Parking/Headlights On Indicator Light
This indicator light will illuminate when the
parking lights or headlights are turned on.
Stop/Start Active Indicator Light —
If Equipped
This indicator light will illuminate when the
Stop/Start function is in “Autostop” mode.
Turn Signal Indicator Lights
When the left or right turn signal is activated,
the turn signal indicator will flash
independently and the corresponding exterior
turn signal lamps will flash. Turn signals can be activated when the multifunction lever is moved down
(left) or up (right).
NOTE:

A continuous chime will sound if the vehicle is driven
more than 1 mile (1.6 km) with either turn signal on.
 Check for an inoperative outside light bulb if either indi -
cator flashes at a rapid rate.
WHITE INDICATOR LIGHTS
Adaptive Cruise Control (ACC) Ready
Indicator Light — If Equipped
This light will turn on when the vehicle
equipped with ACC has been turned on, but not
set.
2WD High Indicator Light — If Equipped
With a Premium Instrument Cluster
This light alerts the driver that the vehicle is in
the Two-Wheel Drive High mode.

Hill Descent Control (HDC) Indicator Light —
If Equipped

This indicator shows when the HDC feature is
turned on. The light will be on solid when HDC
is armed. HDC can only be armed when the
transfer case is in the 4WD Low position and
the vehicle speed is less then 30 mph (48 km/h). If these
conditions are not met while attempting to use the HDC
feature, the HDC indicator light will flash on/off.
CAUTION!
The presence of water in the fuel system circuit may
cause severe damage to the injection system and
irregular engine operation. If the indicator light is
illuminated, contact an authorized dealer as soon as
possible to bleed the system. If the indicator comes on
immediately after refuelling, water, or AdBlue® UREA
has probably been poured into the tank: switch the
engine off immediately and contact an authorized
dealer.
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GETTING TO KNOW YOUR INSTRUMENT PANEL125
ONBOARD DIAGNOSTIC SYSTEM
(OBD II) C
YBERSECURITY
Your vehicle is required to have OBD II and a connection
port to allow access to information related to the
performance of your emissions controls. Authorized
service technicians may need to access this information to
assist with the diagnosis and service of your vehicle and
emissions system
Úpage 184.
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
Maintenance (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.
The OBD II system may not be ready if your vehicle was
recently serviced, recently had a depleted battery or a
battery replacement. If the OBD II system should be
determined not ready for the I/M test, your vehicle may fail
the test.
Your vehicle has a simple ignition actuated test, which you
can use prior to going to the test station. To check if your
vehicle's OBD II system is ready, you must do the following:

1. Cycle the ignition switch to the ON position, but do not crank or start the engine.

NOTE:If you crank or start the engine, you will have to start this
test over.
2. As soon as you cycle the ignition switch to the ON position, you will see the Malfunction Indicator Light
(MIL) symbol come on as part of a normal bulb check. 3. Approximately 15 seconds later, one of two things will
happen:
 The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn OFF
the ignition or start the engine. This means that
your vehicle's OBD II system is not ready and you
should not proceed to the I/M station.
 The MIL will not flash at all and will remain fully illu -
minated until you place the ignition in the off posi -
tion or start the engine. This means that your
vehicle's OBD II system is ready and you can
proceed to the I/M station.
If your OBD II system is not ready, you should see an
authorized dealer or repair facility. If your vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive your vehicle
as you normally would in order for your OBD II system to
update. A recheck with the previously mentioned test
routine may then indicate that the system is now ready.
Regardless of whether your vehicle's OBD II system is
ready or not, if the MIL is illuminated during normal vehicle
operation you should have your vehicle serviced before
going to the I/M station. The I/M station can fail your
vehicle because the MIL is on with the engine running.
WARNING!
 ONLY an authorized service technician should
connect equipment to the OBD II connection port in
order to read the VIN, diagnose, or service your
vehicle.
 If unauthorized equipment is connected to the OBD II
connection port, such as a driver-behavior tracking
device, it may:
 Be possible that vehicle systems, including
safety related systems, could be impaired or a
loss of vehicle control could occur that may
result in an accident involving serious injury or
death.
 Access, or allow others to access, information
stored in your vehicle systems, including
personal information.
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STARTING AND OPERATING127
seconds (or three short pushes in a row) to turn the
engine off. The ignition will remain in the ACC position
(NOT the OFF position) if the engine is turned off when
the transmission is not in PARK.
NOTE:The system will automatically time out and the ignition will
cycle to the OFF position after 30 minutes of inactivity if
the ignition is left in the ACC or RUN (engine not running)
position and the transmission is in PARK.
ENGINE START/STOP Button Functions — With Driver’s
Foot OFF The Brake Pedal (In PARK Or NEUTRAL Position)
The ENGINE START/STOP button operates similar to an
ignition switch. It has three positions: OFF, ACC, and RUN.
To change the ignition positions without starting the
vehicle and use the accessories, follow these steps:

1. Start with the ignition in the OFF position.

2. Push the ENGINE START/STOP button once to place
the ignition to the ACC position (instrument cluster
will display “ACC”).
3. Push the ENGINE START/STOP button a second time to place the ignition to the RUN position (instrument
cluster will display “ON/RUN”).
4. Push the ENGINE START/STOP button a third time to return the ignition to the OFF position (instrument
cluster will display “OFF”).
AUTOPARK
AutoPark is a supplemental feature to assist with placing
the vehicle in PARK should the situations on the following
pages occur. It is a back-up system and should not be relied upon as the primary method by which the driver
shifts the vehicle into PARK.
The conditions under which AutoPark will engage are
outlined on the following pages.
If the vehicle is not in PARK and the driver turns off the
engine, the vehicle may AutoPark.
AutoPark will engage when all of these conditions are met:

Vehicle is equipped with an 8-speed transmission
 Driver’s door is ajar or if the driver’s door is removed
and the driver is not on the seat (seat pad sensor
detects driver missing)
 Vehicle is not in PARK
 Vehicle speed is 1.2 mph (1.9 km/h) or less
 Ignition is switched from RUN to OFF
NOTE:For Keyless Enter ‘n Go™ equipped vehicles, the engine
will turn off and the ignition switch will change to ACC
position.
If the vehicle is not in PARK and the driver exits the vehicle
with the engine running, the vehicle may AutoPark.
AutoPark will engage when all of these conditions are met:
Vehicle is equipped with an 8-speed transmission
 Driver’s door is ajar or if the driver’s door is removed
and the driver is not on the seat (seat pad sensor
detects driver missing)
 Vehicle is not in PARK
 Vehicle speed is 1.2 mph (1.9 km/h) or less
 Driver’s seat belt is unbuckled
 Brake pedal is not pressed
The message “ AutoPark Engaged Shift To P Then Shift To
Gear ” will display in the instrument cluster.
NOTE:In some cases the ParkSense graphic will be displayed in
the instrument cluster. In these cases, the gear selector
must be returned to “P” to select desired gear.
If the driver shifts into PARK while moving, the vehicle may
AutoPark.
AutoPark will engage ONLY when vehicle speed is 1.2 mph
(1.9 km/h) or less.
The message “ Vehicle Speed Is Too High To Shift To P ” will
be displayed in the instrument cluster if vehicle speed is
above 1.2 mph (1.9 km/h).
WARNING!
 Driver inattention could lead to failure to place the
vehicle in PARK. ALWAYS DO A VISUAL CHECK that
your vehicle is in PARK by verifying that a solid (not
blinking) “P” is indicated in the instrument cluster
display and on the gear selector. If the "P" indicator is
blinking, your vehicle is not in PARK. As an added
precaution, always apply the parking brake when
exiting the vehicle.
 AutoPark is a supplemental feature. It is not
designed to replace the need to shift your vehicle
into PARK. It is a back-up system and should not be
relied upon as the primary method by which the
driver shifts the vehicle into PARK.
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128STARTING AND OPERATING
4L
AutoPark will be disabled when operating the vehicle in
4L.
The message “AutoPark Disabled ” will be displayed in the
instrument cluster.
Additional customer warnings will be given when both of
these conditions are met:
 Vehicle is not in PARK
 Driver’s door is ajar
The message “ AutoPark Not Engaged ” will be displayed in
the instrument cluster. A warning chime will continue until
you shift the vehicle into PARK or the driver’s door is
closed.
ALWAYS DO A VISUAL CHECK
that your vehicle is in PARK
by looking for the "P" in the instrument cluster display and
on the gear selector. As an added precaution, always apply
the parking brake when exiting the vehicle.
EXTENDED PARK STARTING
NOTE:Extended Park condition occurs when the vehicle has not
been started or driven for at least 30 days.
1. Install a battery charger or jumper cables to the
battery to ensure a full battery charge during the
crank cycle.

2. Place the ignition in the START position and release it when the engine starts. For vehicles equipped with
the ENGINE START/STOP button, press and hold the
brake pedal while pushing the ENGINE START/STOP
button once.
3. If the engine fails to start within 10 seconds, place the ignition in the OFF position, wait 10 to 15 seconds
to allow the starter to cool, then repeat the “Extended
Park Starting” procedure.
4. If the engine fails to start after eight attempts, allow the starter to cool for at least 10 minutes, then repeat
the procedure.
IF ENGINE FAILS TO START
If the engine fails to start after following the “Normal
Starting” procedure and the vehicle has not experience an
extended park condition, as previously defined, it may be
flooded. Push the accelerator pedal all the way to the floor
and hold it there. Crank the engine for no more than 10 to
15 seconds. This should clear any excess fuel in case the
engine is flooded. Leave the ignition in the RUN position,
release the accelerator pedal and repeat the “Normal
Starting” procedure.
EXTREME COLD WEATHER
(B
ELOW –22°F OR −30°C)
To ensure reliable starting at these temperatures, use of
an externally powered electric engine block heater
(available from an authorized dealer) is recommended.
WARNING!
If vehicle speed is above 1.2 mph (1.9 km/h), the
transmission will default to NEUTRAL until the vehicle
speed drops below 1.2 mph (1.9 km/h). A vehicle left in
the NEUTRAL position can roll. As an added precaution,
always apply the parking brake when exiting the vehicle.
CAUTION!
To prevent damage to the starter, do not crank
continuously for more than 10 seconds at a time. Wait
10 to 15 seconds before trying again.
WARNING!
 Never pour fuel or other flammable liquid into the
throttle body air inlet opening in an attempt to start
the vehicle. This could result in flash fire causing
serious personal injury.
 Do not attempt to push or tow your vehicle to get it
started. Vehicles equipped with an automatic trans -
mission cannot be started this way. Unburned fuel
could enter the catalytic converter and once the
engine has started, ignite and damage the converter
and vehicle.
 If the vehicle has a discharged battery, booster
cables may be used to obtain a start from a booster
battery or the battery in another vehicle. This type of
start can be dangerous if done improperly
Úpage 298.
CAUTION!
To prevent damage to the starter, do not continuously
crank the engine for more than 10 to 15 seconds at a
time. Wait 10 to 15 seconds before trying again.

23_JL_OM_EN_USC_t.book Page 128

130STARTING AND OPERATING
NORMAL STARTING
Observe the instrument cluster lights when starting the
engine.
NOTE:Normal starting of either a cold or a warm engine is
obtained without pumping or pressing 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 illumi -
nated during the preheat process. When the engine Wait
To Start telltale goes off the engine will automatically
crank.
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 ENGINE START/STOP
button again. 5. Check that the Oil Pressure Warning Light has turned
off.
6. Release the parking brake.
STARTING FLUIDS
The engine is equipped with a glow plug preheating
system. If the instructions in this manual are followed, the
engine should start in all conditions and no type of starting
fluid should be used.
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the diesel engine is operating:
 All message center lights are off.
 Malfunction Indicator Light (MIL) is off.
 Engine Oil Pressure telltale is not illuminated.
 Voltmeter operation.
The voltmeter may show a gauge fluctuation at various
engine temperatures. This is caused by the glow plug
heating system. The number of cycles and the length of
the cycling operation is controlled by the engine control
module. Glow plug heater operation can run for several
minutes. Once the heater operation is complete, the
voltmeter needle will stabilize.
CAUTION!
If the Water in Fuel Indicator Light remains on, DO NOT
START the engine before you drain the water from the
fuel filters to avoid engine damage
Úpage 321.
WARNING!
 Do not leave children or animals inside parked vehi -
cles in hot weather. Interior heat buildup may cause
serious injury or death.
 When leaving the vehicle, always make sure the
keyless ignition node is in the OFF position, remove
the key fob from the vehicle and lock the vehicle.
 Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be seri -
ously or fatally injured. Children should be warned
not to touch the parking brake, brake pedal or the
gear selector.
 Do not leave the key fob in or near the vehicle, or in
a location accessible to children, and do not leave
the ignition of a vehicle equipped with Keyless
Enter ‘n Go™ in the ACC or ON/RUN position. A child
could operate power windows, other controls, or
move the vehicle.

23_JL_OM_EN_USC_t.book Page 130

132STARTING AND OPERATING
STOPPING THE ENGINE
After full load operation, idle the engine for a few minutes before shutting it down. This idle period will allow the lubricating oil and coolant to carry excess heat away from the
turbocharger.
NOTE:Refer to the following chart for proper engine shutdown.
NOTE:Under certain conditions the engine fan will run after the
engine is turned off. These conditions are under high load
and high temperature conditions.
COOLING SYSTEM TIPS — AUTOMATIC
T
RANSMISSION
To reduce the potential for engine and transmission
overheating in high ambient temperature conditions, take
the following actions:
 City Driving — When stopped, shift the transmission
into NEUTRAL (N) and increase engine idle speed.
 Highway Driving — Reduce your speed. 
Up Steep Hills — Select a lower transmission gear.
 Air Conditioning — Turn it off temporarily.
NOTE:If the coolant temperature is too high, the A/C will auto -
matically turn off.
Do Not Operate The Engine With Low Oil
Pressure
If the Oil Pressure Warning Light turns on while driving,
stop the vehicle and shut down the engine as soon as
possible. A chime will sound when the light turns on. After
the vehicle is safely stopped, restart the engine and
monitor the Oil Pressure Warning Light. If the Oil Pressure
Warning Light is still illuminated, turn the engine OFF and contact an authorized dealer for further assistance. If the
lamp is no longer illuminated, the engine can be operated
but it is recommended to take the vehicle to an authorized
dealer as soon as possible.
NOTE:Do not operate the vehicle until the cause is corrected.
This light does not show how much oil is in the engine. The
engine oil level must be checked under the hood.
Driving Condition Load Turbocharger Temperature Idle Time (min.) Before Engine Shutdown
Stop and Go EmptyCoolNone
Stop and Go Medium 0.5
Highway Speeds MediumWarm 1.0
City Traffic Maximum GCWR 1.5
Highway Speeds Maximum GCWR 2.0
Uphill Grade Maximum GCWR Hot2.5
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could result
in immediate and severe engine damage.

23_JL_OM_EN_USC_t.book Page 132

STARTING AND OPERATING133
Do Not Operate The Engine With Failed
Parts
All engine failures give some warning before the parts fail.
Be on the alert for changes in performance, sounds, and
visual evidence that the engine requires service. Some
important clues are:
Engine misfiring or vibrating severely
 Sudden loss of power
 Unusual engine noises
 Fuel, oil or coolant leaks
 Sudden change, outside the normal operating range, in
the engine operating temperature
 Excessive smoke
 Oil pressure drop
ENGINE BREAK-IN RECOMMENDATIONS —
GASOLINE ENGINE (IF EQUIPPED)
A long break-in period is not required for the engine and
drivetrain (transmission and axle) in your 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 contributes to a good break-in.
Wide-open throttle acceleration in low gear can be
detrimental and should be avoided.
The engine oil installed in the engine at the factory is a
high-quality energy conserving type lubricant. Oil changes
should be consistent with anticipated climate conditions
under which vehicle operations will occur. For the recommended viscosity and quality grades
Úpage 374.
NOTE:A new engine may consume some oil during its first few
thousand miles (kilometers) of operation. This should be
considered a normal part of the break-in and not inter
-
preted as a problem.
ENGINE BREAK-IN RECOMMENDATIONS —
DIESEL ENGINE (IF EQUIPPED)
The diesel engine does not require a break-in period due
to its construction. Normal operation is allowed, providing
the following recommendations are followed:
 Warm up the engine before placing it under load.
 Do not operate the engine at idle for prolonged periods.
 Use the appropriate transmission gear to prevent
engine lugging.
 Observe vehicle oil pressure and temperature indica -
tors.
 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 towing or no load
operation will extend the time before the engine is at full
efficiency. Reduced fuel economy and power may be seen
at this time.
The engine oil installed in the engine at the factory is a
high-quality energy conserving type lubricant. Oil changes
should be consistent with anticipated climate conditions
under which vehicle operations will occur. For
recommended viscosity and quality grades see
Úpage 374. NON-DETERGENT OR STRAIGHT MINERAL
OILS MUST NEVER BE USED.
PARKING BRAKE
Before exiting the vehicle, make sure that the parking
brake is fully applied. Also, be certain to leave an
automatic transmission in PARK, or manual transmission
in REVERSE or FIRST gear.
The parking brake lever is located in the center console.
To apply the parking brake, pull the lever up as firmly as
possible. To release the parking brake, pull the lever up
slightly, push the center button, then lower the lever
completely.
CAUTION!
Never use Non-Detergent Oil or Straight Mineral Oil in
the engine or damage may result.
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STARTING AND OPERATING137
(Continued)

AUTOMATIC TRANSMISSION — IF EQUIPPED

You must press and hold the brake pedal while shifting out
of PARK.
IGNITION PARK INTERLOCK
This vehicle is equipped with an Ignition Park Interlock
which requires the transmission to be in PARK before the
ignition can be turned to the OFF position. This helps the
driver avoid inadvertently leaving the vehicle without
placing the transmission in PARK. This system also locks
the transmission in PARK whenever the ignition is in the
OFF position.
NOTE:The transmission is NOT locked in PARK when the ignition
is in the ACC position (even though the engine will be off).
Ensure that the transmission is in PARK, and the ignition
is OFF (not in ACC position) before exiting the vehicle.
WARNING!
Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake fully
when exiting the vehicle to guard against vehicle
movement and possible injury or damage.
 Your vehicle could move and injure you and others if
it is not in PARK. Check by trying to move the trans -
mission gear selector out of PARK with the brake
pedal released. Make sure the transmission is in
PARK before exiting the vehicle.
 The transmission may not engage PARK if the vehicle
is moving. Always bring the vehicle to a complete
stop before shifting to PARK, and verify that the
transmission gear position indicator solidly indicates
PARK (P) without blinking. Ensure that the vehicle is
completely stopped, and the PARK position is prop -
erly indicated, before exiting the vehicle.
 It is dangerous to shift out of PARK or NEUTRAL if the
engine speed is higher than idle speed. If your foot is
not firmly pressing the brake pedal, the vehicle could
accelerate quickly forward or in reverse. You could
lose control of the vehicle and hit someone or some -
thing. Only shift into gear when the engine is idling
normally and your foot is firmly pressing the brake
pedal.
 Unintended movement of a vehicle could injure
those in or near the vehicle. As with all vehicles, you
should never exit a vehicle while the engine is
running. Before exiting a vehicle, always come to a
complete stop, then apply the parking brake, shift
the transmission into PARK, and turn the ignition
OFF. When the ignition is in the OFF position, the
transmission is locked in PARK, securing the vehicle
against unwanted movement.
 When exiting the vehicle, always make sure the igni -
tion is in the OFF position, remove the key fob from
the vehicle, and lock the vehicle.
 Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be seri -
ously or fatally injured. Children should be warned
not to touch the parking brake, brake pedal or the
transmission gear selector.
 Do not leave the key fob in or near the vehicle (or in
a location accessible to children), and do not leave
the ignition in the ACC or ON/RUN position. A child
could operate power windows, other controls, or
move the vehicle.
WARNING!CAUTION!
Damage to the transmission may occur if the following
precautions are not observed:
Shift into or out of PARK or REVERSE only after the
vehicle has come to a complete stop.
 Do not shift between PARK, REVERSE, NEUTRAL, or
DRIVE when the engine is above idle speed.
 Before shifting into any gear, make sure your foot is
firmly pressing the brake pedal.
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