check engine JEEP WRANGLER UNLIMITED 2021 Owner handbook (in English)

143
(Continued)
ENGINE BREAK-IN
RECOMMENDATIONS
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 accelera-
tion within the limits of local traffic laws
contributes to a good break-in. Wide-open
throttle acceleration in low gear can be detri -
mental 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 consis -
tent with anticipated climate conditions
under which vehicle operations will occur.
For the recommended viscosity and quality
grades, refer to “Fluids And Lubricants” in
“Technical Specifications”. 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.
AUTOMATIC
TRANSMISSION
NOTE:
You must press and hold the brake pedal
while shifting out of PARK. CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.
CAUTION!
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.
WARNING!
Never use the PARK position as a substi -
tute for the parking brake. Always apply
the parking brake fully when exiting the
vehicle to guard against vehicle move-
ment 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 transmission gear
selector out of PARK with the brake
pedal released. Make sure the transmis-
sion 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 posi -
tion is properly indicated, before exiting
the vehicle.
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STARTING AND OPERATING
154
Automatic Mode
The Stop/Start feature is enabled
after every normal customer engine
start. At that time, the system will
go into STOP/START READY and if
all other conditions are met, can go into a
STOP/START AUTOSTOP ACTIVE
“Autostop” mode.
To Activate The Autostop Mode, The Following
Must Occur:
The system must be in STOP/START
READY state. A STOP/START READY
message will be displayed in the instru -
ment cluster display within the Stop/Start
section. Refer to “Instrument Cluster” in
“Getting To Know Your Instrument Panel”
in your Owner’s Manual for further infor -
mation.
The vehicle must be completely stopped.
The shifter must be in a forward gear and
the brake pedal depressed.
The engine will shut down, the tachometer
will move to the zero position and the Stop/
Start telltale will illuminate indicating you
are in Autostop. Customer settings will be
maintained upon return to an engine running
condition. Refer to the “Stop/Start System” in the
“Starting And Operating” section located in
your Owner’s Manual for further information.
Possible Reasons The Engine Does Not
Autostop
Prior to engine shut down, the system will
check many safety and comfort conditions to
see if they are fulfilled. Detailed information
about the operation of the Stop/Start system
may be viewed in the instrument cluster
display Stop/Start Screen. In the following
situations, the engine will not stop:
Driver’s seat belt is not buckled.
Driver’s door is not closed.
Battery temperature is too warm or cold.
Battery charge is low.
The vehicle is on a steep grade.
Cabin heating or cooling is in process and
an acceptable cabin temperature has not
been achieved.
HVAC is set to full defrost mode at a high
blower speed.
HVAC set to MAX A/C.
Engine has not reached normal operating
temperature.
Engine temperature too high.
The transmission is not in a forward gear.
Hood is open.
Transfer case is in 4L or Neutral.
Brake pedal is not pressed with sufficient
pressure.
Other Factors Which Can Inhibit Autostop
Include:
Accelerator pedal input.
Vehicle speed threshold not achieved from
previous auto-stop.
Steering angle beyond threshold. (ESS
Models Only)
ACC is on and speed is set.
Vehicle is at high altitude.
System fault present.
It may be possible for the vehicle to be driven
several times without the Stop/Start system
going into a STOP/START READY state
under more extreme conditions of the items
listed above.
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STARTING AND OPERATING
172
AdBlue® (UREA) Storage
AdBlue® (UREA) is considered a very stable
product with a long shelf life. If AdBlue®
(UREA) is kept in temperatures between 10°
and 90°F (-12° and 32°C), it will last a
minimum of one year.
AdBlue® (UREA) is subject to freezing at the
lowest temperatures. For example, AdBlue®
(UREA) may freeze at temperatures at or
below 12°F (-11°C). The system has been
designed to operate in this environment.
NOTE:
When working with AdBlue® (UREA), it is
important to know that:
Any containers or parts that come into
contact with AdBlue® (UREA) must be
AdBlue® (UREA) compatible (plastic or
stainless steel). Copper, brass, aluminum,
iron or non-stainless steel should be
avoided as they are subject to corrosion by
AdBlue® (UREA).
If AdBlue® (UREA) is spilled, it should be
wiped up completely.
Adding AdBlue® (UREA)
Preliminary Conditions
AdBlue® (UREA) freezes at temperatures
lower than 12°F (-11°C). If the car stands for
a long time at this temperature refilling
could be difficult. For this reason, it is
advised to park the vehicle in a garage and/
or heated environment and wait for the urea
to return to liquid state before topping up.
Proceed as follows:
Park the car on flat ground and stop the
engine by placing the ignition to the OFF
position.
Open the fuel door, undo and remove the
cap (blue) from the AdBlue® (UREA)
filler.
Refilling With Nozzles
You can fill up at any AdBlue® (UREA)
distributor.
Proceed as follows:
Insert the AdBlue® (UREA) nozzle in the
filler, start refilling and stop refilling at the
first shut-off (the shut-off indicates that the AdBlue® (UREA) tank is full). Do not
proceed with the refilling, to prevent
spillage of AdBlue® (UREA).
Extract the nozzle.
Refilling With Containers
Proceed as follows:
Check the expiration date.
Read the advice for use on the label before
pouring the content of the bottle into the
AdBlue® (UREA) tank.
If systems which cannot be screwed in
(e.g. tanks) are used for refilling, after the
indication appears on the instrument
panel display refer to “Warning lights And
Messages” in the “Getting To Know Your
Instrument Panel” for further information,
fill the AdBlue® (UREA) tank with no
more than 2 Gallons (8 liters).
If containers which can be screwed to the
filler are used, the reservoir is full when
the AdBlue® (UREA) level in the
container stops pouring out. Do not
proceed further.
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STARTING AND OPERATING
178
12. Shift the transmission into PARK (NOT inNEUTRAL).
13. Attach the vehicle to the tow vehicle using a suitable tow bar.
14. Release the parking brake.
15. Disconnect the negative battery cable, and secure it away from the negative
battery post.Shifting Out of NEUTRAL (N)
Use the following procedure to prepare your
vehicle for normal usage.
1. Bring the vehicle to a complete stop,leaving it connected to the tow vehicle.
2. Firmly apply the parking brake.
3. Reconnect the negative battery cable.
4. Start the engine.
5. Press and hold the brake pedal.
6. Shift the transmission into NEUTRAL.
7. Turn the engine OFF.
8. Shift the transfer case lever to the desired position.
NOTE:
When shifting the transfer case out of
NEUTRAL (N), the engine should remain Off
to avoid gear clash. 9. Shift the transmission into PARK.
10. Release the brake pedal.
11. Disconnect vehicle from the tow vehicle.
12. Start the engine.
13. Press and hold the brake pedal.
14. Release the parking brake.
15. Shift the transmission into gear, release
the brake pedal, and check that the
vehicle operates normally.
CAUTION!
Damage to the transmission may occur if
the transmission is shifted into PARK with
the transfer case in NEUTRAL (N) and the
engine running. With the transfer case in
NEUTRAL (N) ensure that the engine is
OFF before shifting the transmission into
PARK.
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183
(Continued)
Center High Mounted Stop Lamp (CHMSL)
Please see an authorized dealer for service.
License Plate Lamps
1. Reach under the vehicle to access theback of the lamp.
2. Firmly grasp the bulb by the two latch features and squeeze them together to
unlock the bulb from the back of the
lamp housing.
Rear Fog Lamp
NOTE:
We advise referring to an authorized dealer
for service.
1. Reach under the vehicle to access theback of the fog lamp.
2. Disconnect the wire harness connector from the fog lamp connector receptacle.
3. Rotate the socket a quarter turn counter -
clockwise, then remove it from the
housing.
4. Pull the bulb straight out from the keyed opening in the housing and then connect
the replacement bulb and reassemble.
FUSES
General Information
The fuses protect electrical systems against
excessive current.
When a device does not work, you must
check the fuse element inside the blade fuse
for a break/melt.
Also, please be aware that when using power
outlets for extended periods of time with the
engine off may result in vehicle battery
discharge.
CAUTION!
Do not touch the new bulb with your
fingers. Oil contamination will severely
shorten bulb life. If the bulb comes in
contact with any oily surface, clean the
bulb with rubbing alcohol.
WARNING!
When replacing a blown fuse, always use
an appropriate replacement fuse with
the same amp rating as the original fuse.
Never replace a fuse with another fuse of
higher amp rating. Never replace a blown
fuse with metal wires or any other mate-
rial. Failure to use proper fuses may
result in serious personal injury, fire and/
or property damage.
Before replacing a fuse, make sure that
the ignition is off and that all the other
services are switched off and/or disen -
gaged.
If the replaced fuse blows again, contact
an authorized dealer.
If a general protection fuse for safety
systems (air bag system, braking
system), power unit systems (engine
system, gearbox system) or steering
system blows, contact an authorized
dealer.
CAUTION!
If it is necessary to wash the engine
compartment, take care not to directly hit
the fuse box, and the windshield wiper
motors with water.
WARNING! (Continued)
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210
SERVICING AND MAINTENANCE
SCHEDULED SERVICING
Correct servicing is crucial for guaranteeing a
long life for the car under the best condi-
tions. For this reason, Jeep has planned a
series of checks and services at fixed
distance intervals and, where provided, at
fixed time intervals, as described in the
Scheduled Servicing plan. To keep the car’s
efficiency in tip-top condition, in the
following Scheduled Service plan pages a
few additional checks are listed that should
be carried out more frequently with respect
to the normal coupon redemption schedule.
Scheduled Servicing is offered by all autho -
rized dealerships according to fixed time or
mileage intervals. If, during each operation,
in addition to the ones scheduled, the need
arises for further replacements or repairs,
these may be carried out with the owner's
explicit agreement only.
The technicians at your dealership know your
vehicle best, and have access to factory
trained information, genuine Mopar parts,
and specially designed electronic and
mechanical tools that can help prevent
future costly repairs. If your car is used
frequently for towing, the interval between
one scheduled servicing operation and the next should be reduced. More frequent main
-
tenance may be needed for vehicles in severe
operating conditions, such as dusty areas
and very short trip driving.
NOTE:
Scheduled Servicing interventions are set
out by the Manufacturer. Failure to have
them carried out may invalidate the
warranty. It is advised to inform an autho -
rized dealership of any small operating irreg -
ularities without waiting for the next service.
Scheduled Servicing — Gasoline Engine
The oil change indicator system (if
equipped) will remind you that it is time to
take your vehicle in for engine oil replace -
ment.
On vehicles equipped with instrument
cluster display, “Oil Change Required” will
be displayed and a single chime will sound,
indicating that an oil change is necessary.
On non-instrument cluster display equipped
vehicles, “Change Oil” will flash in the
instrument cluster odometer and a single
chime will sound, indicating that an oil
change is necessary. The oil change indicator message will illumi
-
nate approximately 7,000 miles
(11,200 km) after the most recent oil
change was performed. Have your vehicle
serviced as soon as possible, within
500 miles (800 km). However, an earlier oil
change at 4,500 miles (7,500 km) may be
required if the vehicle is operated under
“Severe Duty Conditions” later in this
section.
NOTE:
The oil change indicator message will not
monitor the time since the last oil change.
Change your vehicle's oil if it has been
12 months since your last oil change even
if the oil change indicator message is NOT
illuminated.
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 7,500 miles
(12,000 km) or 12 months, whichever
comes first.
An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change.
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211
Once A Month Or Before A Long Trip
Check the engine oil level about five
minutes after a fully warmed engine is
shut off. Checking the oil level while the
vehicle is on level ground will improve the
accuracy 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.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear.
Inspect the battery and clean and tighten
the terminals as required.
Check the fluid levels of coolant reservoir,
brake master cylinder and power steering
and fill 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.
Inspect the CV/Universal joints.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear, even if it occurs
before the oil indicator system turns on.
Required Maintenance Intervals
Refer to the Maintenance Plan on the
following pages for the required maintenance
intervals.
Maintenance Plan
NOTE:
Once you have carried out the last interven -
tion in the table, continue with the sched -
uled servicing, maintaining the frequency
indicated in the plan by marking each oper -
ation with a dot or dedicated note. Simply
restarting the maintenance from the start of
the plan may cause the allowed interval to be
exceeded for some operations.
CAUTION!
Failure to perform the required
maintenance items may result in damage
to the vehicle.
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217
Once A Month Or Before A Long Trip
Check engine oil level.
Check windshield washer fluid level.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear, even if it occurs
before the oil indicator system turns on.

Check the fluid levels of the coolant reservoir
and brake master cylinder, fill as needed.

Check function of all interior and exterior lights.Demanding Vehicle Use
Restore additive level for AdBlue® Diesel
emissions (UREA) (if equipped), when the
lamp is illuminated or the message on the
instrument panel.
Maintenance Plan — Diesel Engine
Required Maintenance Intervals
Refer to the maintenance plan on the
following pages for the required maintenance
intervals.
NOTE:
Once you have carried out the last intervention in the table, continue with the scheduled servicing, maintaining the frequency indicated in
the plan by marking each operation with a dot or dedicated note. Simply restarting the maintenance from the start of the plan may cause the
allowed interval to be exceeded for some operations.
CAUTION!

Failure to perform the required maintenance
items may result in damage to the vehicle.

At Every Oil Change Interval As Indicated By Oil Change Indicator System:
Change oil and filter
Rotate the tires. Rotate at the first sign of irregular wear, even if it occurs before the oil indicator system turns on
Inspect battery and clean and tighten terminals as required
Inspect the CV/Universal joints
Inspect brake pads, shoes, rotors, drums, hoses and park brake
Inspect engine cooling system protection and hoses
Inspect exhaust system
Inspect engine air cleaner if using in dusty or off-road conditions
Inspect all door latches for presence of grease, reapply if necessary.
Inspect coolant level.
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SERVICING AND MAINTENANCE
218Mileage or time passed (whichever comes first)
12,500
25,000
37,500
50,000
62,500
75,000
87,500
100,000
112,500
125,000
137,500
150,000
162,500
175,000
187,500
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
180,000
200,000
220,000
240,000
260,000
280,000
300,000
Additional Inspections
Change the engine oil and engine oil filter. (*)
Inspect the CV/Universal joints. X X X X X X X X X X X X X X X
Inspect front suspension, rear suspension, boot seals,
tie rod ends, and replace if necessary. X X X X X X X
Visually inspect condition of: exterior bodywork,
underbody protection, pipes and hoses (exhaust - fuel
system - brakes), rubber elements (boots, sleeves,
bushings, etc.). X X X X X X X
If using your vehicle in dusty or off-road conditions,
inspect the air cleaner filter, and replace if necessary. X X X X X X X X X X X X X X X
Inspect the brake linings, parking brake function. X X X X X X X
Check and, if necessary, top up fluid levels. (°) X X X X X X X X X X X X X X X
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SERVICING AND MAINTENANCE
224
(Continued)
Checking Oil Level — Gasoline Engine
To ensure proper lubrication of your vehicle's
engine, the engine oil must be maintained at
the correct level. The engine oil level should
be checked five minutes after a warmed up
engine has been shut off.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil
level readings. Always maintain the oil level
within the SAFE zone on the dipstick. Adding
1 quart (0.95 liters) of oil when the reading
is at the bottom of the crosshatch zone will
result in a reading at the top of the cross-
hatch zone on these engines.
Adding Washer Fluid
The fluid reservoir for the windshield
washers and the rear window washer (if
equipped) 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 solu -
tion or mixture that meets or exceeds the
temperature range of your climate. This
rating information can be found on most
washer fluid containers. WARNING!

Never smoke while working in the engine
compartment: gas and inflammable vapors
may be present, with the risk of fire.

Be very careful when working in the
engine compartment when the engine is
hot: you may get burned. Do not get too
close to the radiator cooling fan: the
electric fan may start; danger of injury.
Scarves, ties and other loose clothing
might be pulled by moving parts.
CAUTION!
Be careful not to confuse the various
types of fluids while topping up: they are
not compatible with each other! Topping
up with an unsuitable fluid could
severely damage your car.
The oil level must never exceed the MAX
mark.
Always top up using engine oil of the
same specifications as that already in
the engine.
If the engine oil is being topped up, wait
for the engine to cool down before loos-
ening the filler cap, particularly for vehi -
cles with aluminium cap (if equipped).
WARNING: risk of burns!
Overfilling or underfilling the crankcase
will cause aeration or loss of oil pressure.
This could damage your engine.
CAUTION! (Continued)
WARNING!
Commercial windshield washer solvents
are flammable. They could ignite and burn
you. Care must be exercised when filling or
working around the washer solution.
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