2023 JEEP GLADIATOR check engine

SERVICING AND MAINTENANCE357
SCHEDULED SERVICING — DIESEL ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change indicator
system will remind you that it is time to take your
vehicle in for scheduled maintenance.
Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent short-trips,
trailer tow, extremely hot or cold ambient
temperatures will influence when the “Oil Change
Required” message is displayed. Have your vehicle
serviced as soon as possible, within the next
500 miles (805 km).
An authorized dealer will reset the oil change
indicator message after completing the scheduled
oil change. If a scheduled oil change is performed
by someone other than an authorized dealer, to
reset the message Úpage 121.
NOTE:Under no circumstances should oil change
intervals exceed 10,000 miles (16,000 km) or
12 months, whichever comes first.
Engine Oil Filter Replacement
Residual oil in the housing may spill from the
housing when the new filter is installed if the
residual oil is not either removed from the housing
or enough time has not elapsed to allow the oil to
drain back into the engine. When servicing the oil
filter on this engine, open the filter cap
approximately six turns until the cap o-ring is
visible and stop. Wait five minutes with the cap in
this position to allow dirty engine oil to drain back
into the engine. After five minutes, the cap and
filter assembly can be removed and discarded. Once A Month Or Before A Long Trip:Check engine oil level
Check windshield washer fluid level
Check the tire pressures and look for unusual
wear or damage
Check the fluid levels of the coolant reservoir,
brake master cylinder, and fill as needed
Check function of all interior and exterior lights
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364SERVICING AND MAINTENANCE
(Continued)
CHECKING OIL LEVEL
To ensure proper engine lubrication, the engine oil
must be maintained at the correct level. Check the
oil level at regular intervals, such as every fuel
stop. The best time to check the engine oil level is
about five minutes after a fully warmed up engine
is shut off.
Checking the oil while the vehicle is on level ground
will improve the accuracy of the oil level readings.
There are four possible dipstick types:
Crosshatched zone.
Crosshatched zone marked SAFE.
Crosshatched zone marked with MIN at the low
end of the range and MAX at the high end of the
range.
Crosshatched zone marked with dimples at the
MIN and the MAX ends of the range.
NOTE:Always maintain the oil level within the crosshatch
markings on the dipstick.
Adding 1 qt (1 L) of oil when the reading is at the
low end of the dipstick range will raise the oil level
to the high end of the range marking.
ADDING WASHER FLUID
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 solution or mixture
that meets or exceeds the temperature range of
your climate. This rating information can be found
on most washer fluid containers.
MAINTENANCE-FREE BATTERY
Your vehicle is equipped with a maintenance-free
battery. You will never have to add water, and
periodic maintenance is not required.
CAUTION!
Overfilling or underfilling the crankcase will
cause aeration or loss of oil pressure. This could
damage your engine.
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.
WARNING!
Battery fluid is a corrosive acid solution and
can burn or even blind you. Do not allow
battery fluid to contact your eyes, skin, or
clothing. Do not lean over a battery when
attaching clamps. If acid splashes in eyes or
on skin, flush the area immediately with large
amounts of water Úpage 343.
Battery gas is flammable and explosive. Keep
flame or sparks away from the battery. Do not
use a booster battery or any other booster
source with an output greater than 12 Volts.
Do not allow cable clamps to touch each
other.
Battery posts, terminals, and related accesso -
ries contain lead and lead compounds. Wash
hands after handling.

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SERVICING AND MAINTENANCE377
COOLING SYSTEM
Coolant Checks
Check the engine coolant (antifreeze) protection
every 12 months (before the onset of freezing
weather, where applicable). If the engine coolant is
dirty or rusty in appearance, the system should be
drained, flushed, and refilled with fresh Organic
Additive Technology (OAT) coolant (conforming to MS.90032) by an authorized dealer. Check the
front of the A/C condenser (if equipped) or radiator
for any accumulation of bugs, leaves, etc. If dirty,
clean by gently spraying water from a garden hose
vertically down the face of the A/C condenser (if
equipped) or the back of the radiator core.
Check the engine cooling system hoses for brittle
rubber, cracking, tears, cuts, and tightness of the
connection at the coolant recovery bottle and
radiator. Inspect the entire system for leaks. DO
NOT REMOVE THE COOLANT PRESSURE CAP
WHEN THE COOLING SYSTEM IS HOT.
Cooling System — Drain, Flush, And Refill
Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly
could lead to severe internal engine damage. If any
coolant is needed to be added to the system
please contact an authorized dealer.
If the engine coolant (antifreeze) is dirty or
contains visible sediment, have an authorized
dealer clean and flush with OAT coolant
(conforming to MS.90032).
For the proper maintenance intervals see
Ú
page 354 for gas engines or Ú page 358 for
diesel engines.
Selection Of Coolant
For further information Ú page 424.
NOTE:
Mixing of engine coolant (antifreeze), other than
specified Organic Additive Technology (OAT)
engine coolant, may result in engine damage
and may decrease corrosion protection. OAT
engine coolant is different and should not be
mixed with Hybrid Organic Additive Technology
(HOAT) engine coolant or any “globally compat -
ible” coolant. If a non-OAT engine coolant is
introduced into the cooling system in an emer -
gency, the cooling system will need to be
drained, flushed, and refilled with fresh OAT
coolant (conforming to MS.90032), by an autho -
rized dealer as soon as possible.
Do not use water alone or alcohol-based engine
coolant products. Do not use additional rust
inhibitors or anti-rust products, as they may not
be compatible with the radiator engine coolant
and may clog the radiator.
This vehicle has not been designed for use with
propylene glycol-based engine coolant. Use of
propylene glycol-based engine coolant is not
recommended.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added to
the system please contact an authorized dealer.
WARNING!
You or others can be badly burned by hot
engine coolant (antifreeze) or steam from your
radiator. If you see or hear steam coming from
under the hood, do not open the hood until the
radiator has had time to cool. Never open a
cooling system pressure cap when the radi -
ator or coolant bottle is hot.
Keep hands, tools, clothing, and jewelry away
from the radiator cooling fan when the hood is
raised. The fan starts automatically and may
start at any time, whether the engine is
running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the igni -
tion to the OFF position. The fan is tempera -
ture controlled and can start at any time the
ignition is in the ON position.
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378SERVICING AND MAINTENANCE
Adding Coolant

Your vehicle has been built with an improved engine
coolant (OAT coolant conforming to MS.90032) that
allows extended maintenance intervals. This engine
coolant (antifreeze) can be used up to 10 years or
150,000 miles (240,000 km) before replacement.
To prevent reducing this extended maintenance
period, it is important to use the same engine
coolant (OAT coolant conforming to MS.90032)
throughout the life of your vehicle.

Please review these recommendations for using
Organic Additive Technology (OAT) engine coolant
that meets the requirements of the manufacturer
Material Standard MS.90032. When adding
engine coolant (antifreeze):
We recommend using Mopar® Antifreeze/
Coolant 10 Year/150,000 Mile (240,000 km)
Formula OAT (Organic Additive Technology) that
meets the requirements of the manufacturer
Material Standard MS.90032.
Mix a minimum solution of 50% OAT engine
coolant that meets the requirements of the
manufacturer Material Standard MS.90032
and distilled water. Use higher concentrations
(not to exceed 70%) if temperatures below
-34°F (-37°C) are anticipated. Please contact
an authorized dealer for assistance.
Use only high purity water, such as distilled or
deionized water, when mixing the water/engine coolant solution. The use of lower quality water
will reduce the amount of corrosion protection
in the engine cooling system.
NOTE:
It is the owner's responsibility to maintain the
proper level of protection against freezing
according to the temperatures occurring in the
area where the vehicle is operated.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added to
the system, please contact an authorized
dealer.
Mixing engine coolant types is not recom
-
mended and can result in cooling system
damage. If HOAT and OAT coolant are mixed in
an emergency, have an authorized dealer drain,
flush, and refill with OAT coolant (conforming to
MS.90032) as soon as possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
engine coolant (antifreeze), and to ensure that
engine coolant will return to the radiator from the
coolant expansion bottle/recovery tank if so
equipped.
The cap should be inspected and cleaned if there
is any accumulation of foreign material on the
sealing surfaces.
Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze)
OAT or HOAT, is a regulated substance requiring
proper disposal. Check with your local authorities
to determine the disposal rules for your
community. To prevent ingestion by animals or
children, do not store ethylene glycol-based
coolant in open containers or allow it to remain in
puddles on the ground, clean up any ground spills
immediately. If ingested, seek emergency
assistance immediately.
WARNING!
Do not open hot engine cooling system. Never
add engine coolant (antifreeze) when the
engine is overheated. Do not loosen or
remove the cap to cool an overheated engine.
Heat causes pressure to build-up in the
cooling system. To prevent scalding or injury,
do not remove the pressure cap while the
system is hot or under pressure.
Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or
engine damage may result.

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SERVICING AND MAINTENANCE379
Coolant Level
The coolant bottle provides a quick visual method
for determining that the coolant level is adequate.
With the engine in the off and cold, the level of the
engine coolant (antifreeze) in the bottle should be
between the ranges indicated on the bottle.
The radiator normally remains completely full, so
there is no need to remove the radiator/coolant
pressure cap unless checking for engine coolant
freeze point or replacing coolant. Advise your
service attendant of this. As long as the engine
operating temperature is satisfactory, the coolant
only needs to be checked once a month.
When additional engine coolant is needed to
maintain the proper level, only OAT coolant that
meets the requirements of FCA Material Standard
MS.90032 should be added to the coolant bottle.
Do not overfill.
Cooling System Notes
NOTE:When the vehicle is stopped after a few miles/kilo -
meters of operation, you may observe vapor
coming from the front of the engine compartment.
This is normally a result of moisture from rain,
snow, or high humidity accumulating on the
radiator and being vaporized when the thermostat
opens, allowing hot engine coolant (antifreeze) to
enter the radiator. If an examination of your engine compartment
shows no evidence of radiator or hose leaks, the
vehicle may be safely driven. The vapor will soon
dissipate.
Do not overfill the coolant expansion bottle.
Check the freezing point of the coolant in the
radiator and in the coolant expansion bottle. If
determined that more engine coolant needs to
be added to the radiator, the contents of the
coolant expansion bottle must also be protected
against freezing.
If frequent engine coolant additions are
required, the cooling system should be pressure
tested for leaks.
Maintain engine coolant concentration at a
minimum of 50% OAT coolant (conforming to
MS.90032) and distilled water for proper corro
-
sion protection of your engine which contains
aluminum components.
Make sure that the coolant expansion bottle
overflow hoses are not kinked or obstructed.
Keep the front of the radiator clean. With air
conditioning, keep the front of the condenser
clean.
Do not change the thermostat for Summer or
Winter operation. If replacement is ever neces -
sary, install ONLY the correct type thermostat. Other designs may result in unsatisfactory
engine system performance, poor gas mileage,
and increased emissions.
CHARGE AIR COOLER — INTER-COOLER
(D
IESEL ENGINE)
The charge air cooler is positioned in front of the
radiator and the air conditioner condenser. Air
enters the engine through the air cleaner and
passes through the turbocharger, where it is
pressurized. This pressurized air rapidly reaches
high temperature. The air is then directed through
a hose to the charge air cooler and through
another hose to the intake manifold of the engine.
This cooling process enables more efficient
burning of fuel resulting in fewer emissions.
To guarantee optimum performance of the system,
keep the surfaces of the charge air cooler,
condenser and radiator clean and free of debris.
Periodically check the hoses leading to and from
the charge air cooler for cracks or loose clamps
resulting in loss of pressure and reduced engine
performance.
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380SERVICING AND MAINTENANCE
(Continued)
BRAKE SYSTEM
In order to ensure brake system performance, all
brake system components should be inspected
periodically. For the proper maintenance intervals
Úpage 354.
Fluid Level Check — Brake Master Cylinder
The fluid level of the master cylinder should be
checked whenever the vehicle is serviced, or
immediately if the Brake System Warning Light is
on. If necessary, add fluid to bring level within the
designated marks on the side of the reservoir of
the brake master cylinder. Be sure to clean the top
of the master cylinder area before removing cap.
With disc brakes, fluid level can be expected to fall
as the brake pads wear. Brake fluid level should be
checked when pads are replaced. If the brake fluid
is abnormally low, check the system for leaks.
For further information Ú page 426.
FRONT/REAR AXLE FLUID
For normal service, periodic fluid level checks are
not required. When the vehicle is serviced for other
reasons the exterior surfaces of the axle assembly
should be inspected. If gear oil leakage is
suspected, inspect the fluid level.
Fluid Level Check
Lubricant should be approximately 1/8 inch
(3 mm) below the bottom edge of the oil fill hole.
NOTE:Make sure that the vehicle is level and supported
by the axles.
Adding Fluid
Add lubricant only at the fill hole and only to the
level specified above.
Selection Of Lubricant
Use only the manufacturer’s recommended fluid
Úpage 426.
WARNING!
Riding the brakes can lead to brake failure and
possibly a collision. Driving with your foot resting
or riding on the brake pedal can result in
abnormally high brake temperatures, excessive
lining wear, and possible brake damage. You
would not have your full braking capacity in an
emergency.
WARNING!
Use only manufacturer recommended brake
fluid Ú page 426. Using the wrong type of
brake fluid can severely damage your brake
system and/or impair its performance. The
proper type of brake fluid for your vehicle is
also identified on the original factory installed
hydraulic master cylinder reservoir.
To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that
has been in a tightly closed container. Keep
the master cylinder reservoir cap secured at
all times. Brake fluid in a open container
absorbs moisture from the air resulting in a
lower boiling point. This may cause it to boil
unexpectedly during hard or prolonged
braking, resulting in sudden brake failure. This
could result in a collision.
Overfilling the brake fluid reservoir can result
in spilling brake fluid on hot engine parts,
causing the brake fluid to catch fire. Brake
fluid can also damage painted and vinyl
surfaces, care should be taken to avoid its
contact with these surfaces.
Do not allow petroleum based fluid to contam -
inate the brake fluid. Brake seal components
could be damaged, causing partial or
complete brake failure. This could result in a
collision.
WARNING!

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SERVICING AND MAINTENANCE381
TRANSFER CASE
Fluid Level Check
The fluid level should be to the bottom edge of the
fill hole when the vehicle is in a level position.

Transfer Case

Drain And Refill
For the proper maintenance intervals Úpage 354.
Selection Of Lubricant
Use only the manufacturer’s recommended fluid
Úpage 426.
MANUAL TRANSMISSION — IF EQUIPPED
Fluid Level Check
Check the fluid level by removing the fill plug. The
fluid level should be between the bottom of the fill
hole and a point not more than 3/16 of an inch
(4.76 mm) below the bottom of the hole.
Add fluid, if necessary, to maintain the proper
level.
Frequency Of Fluid Change
Under normal operating conditions, the fluid
installed at the factory will give satisfactory
lubrication for the life of the vehicle. If the fluid
becomes contaminated with water, it should be
changed immediately. Otherwise, change the fluid
as recommended in the Maintenance Plan
Úpage 354.
Selection Of Lubricant
Use only manufacturer's recommended manual
transmission fluid Ú page 424.
AUTOMATIC TRANSMISSION —
I
F EQUIPPED
Special Additives
It is strongly recommended against using any
special additives in the transmission. Automatic
Transmission Fluid (ATF) is an engineered product
and its performance may be impaired by
supplemental additives. Therefore, do not add any
fluid additives to the transmission. Avoid using
transmission sealers as they may adversely affect
seals.
1 — Fill Hole
2 — Drain Hole
CAUTION!
Do not use chemical flushes in your transmis -
sion as the chemicals can damage your trans -
mission components. Such damage is not
covered by the New Vehicle Limited Warranty.
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SERVICING AND MAINTENANCE383
The fuses protect electrical systems against
excessive electrical 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 an extended period of time with the
engine off, it may result in vehicle battery
discharge.
Blade Fuses

Power Distribution Center (PDC)
The Power Distribution Center is located in the
engine compartment near the battery. This center
contains cartridge fuses, mini fuses, and relays.
The PDC top cover is labeled with each serviceable
fuse/relay location, function, and size.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.
WARNING!
1 — Fuse Element
2 — Blade Fuse with a good/functional fuse
element
3 — Blade fuse with a bad/not functional fuse
element (blown fuse)
CAUTION!
When installing the power distribution center
cover, it is important to ensure the cover is
properly positioned and fully latched. Failure to
do so may allow water to get into the power
distribution center and possibly result in an
electrical system failure.
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