check engine JEEP GLADIATOR 2023 User Guide

138GETTING TO KNOW YOUR INSTRUMENT PANEL
AdBlue® (UREA) Injection System Failure
Warning Light — If Equipped
This warning light will illuminate along
with a dedicated message on the display
(if equipped) if an unknown fluid not
conforming with acceptable
characteristics is inserted, or if an average
consumption of AdBlue® (UREA) over 50% is
detected. Contact an authorized dealer as soon as
possible. If the problem is not solved, a specific message will
appear on the Instrument Cluster Display
whenever a certain threshold is reached until it will
no longer be possible to start the engine.
When about 125 miles (200 km) are remaining
before the AdBlue® (UREA) tank is empty, a
continuous dedicated message will appear on the
instrument panel, accompanied by a buzzer sound
(if equipped).
YELLOW INDICATOR LIGHTS
4WD Indicator Light — If Equipped
This light alerts the driver that the vehicle
is in the four-wheel drive mode, and the
front and rear driveshafts are
mechanically locked together forcing the
front and rear wheels to rotate at the same speed.
4WD Low Indicator Light — If Equipped
This light alerts the driver that the vehicle
is in the 4WD Low mode. The front and
rear driveshafts are mechanically locked
together forcing the front and rear
wheels to rotate at the same speed. Low range
provides a greater gear reduction ratio to provide
increased torque at the wheels.
4WD Part Time Indicator Light —
If Equipped
This light alerts the driver that the vehicle
is in the four-wheel drive part time mode,
and the front and rear driveshafts are
mechanically locked together forcing the
front and rear wheels to rotate at the same speed.
Axle Locker Fault Indicator Light —
If Equipped
This light indicates when front and/or
rear axle locker fault has been detected.
Rear Axle Lock Indicator Light —
If Equipped
This light indicates when the rear axle
lock has been activated Ú page 161.
Front And Rear Axle Lock Indicator Light —
If Equipped
This light indicates when the front, rear,
or both axles have been locked. The
telltale will display the lock icon on the
front and rear axles to indicate the
current lock status.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures
and warning have been established for the tire
size equipped on your vehicle. Undesirable
system operation or sensor damage may result
when using replacement equipment that is not
of the same size, type, and/or style. Aftermarket
wheels can cause sensor damage. Using
aftermarket tire sealants may cause the Tire
Pressure Monitoring System (TPMS) sensor to
become inoperable. After using an aftermarket
tire sealant it is recommended that you take
your vehicle to an authorized dealer to have your
sensor function checked.

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142GETTING TO KNOW YOUR INSTRUMENT PANEL
If any of these systems require service, the OBD II
system will turn on the Malfunction Indicator Light
(MIL). It will also store diagnostic codes and other
information to assist your service technician in
making repairs. Although your vehicle will usually
be drivable and not need towing, see an authorized
dealer for service as soon as possible.
ONBOARD DIAGNOSTIC SYSTEM
(OBD II) C
YBERSECURITY
Your vehicle is required to have an 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 Ú page 214.
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 and/or provinces 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.
CAUTION!
Prolonged driving with the MIL on could cause
further damage to the emission control
system. It could also affect fuel economy and
driveability. The vehicle must be serviced
before any emissions tests can be performed.
If the MIL is flashing while the vehicle is
running, severe catalytic converter damage
and power loss will soon occur. Immediate
service is required.
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, infor -
mation stored in your vehicle systems,
including personal information.

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GETTING TO KNOW YOUR INSTRUMENT PANEL143
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 illuminated until you place the ignition
in the off position 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, 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.3

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STARTING AND OPERATING145
however the ignition will remain in the ACC
position (NOT the OFF position). Never leave a
vehicle out of the PARK position, or it could roll.
3. If the gear selector is in NEUTRAL, and the vehicle speed is below 5 mph (8 km/h),
pushing the ENGINE START/STOP button once
will turn the engine off. The ignition will remain
in the ACC position.
4. If the vehicle speed is above 5 mph (8 km/h), the ENGINE START/STOP button must be held
for two 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 modes: OFF, ACC,
and RUN. To change the ignition modes without
starting the vehicle and use the accessories, follow
these steps:
1. Starting 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 in
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 transmis
-
sion
Driver door is ajar or if the driver door is
removed and the driver is not on the seat (seat
pad sensor detects driver missing)
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 precau -
tion, 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.
4

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146STARTING AND OPERATING
Vehicle is not in PARK
Vehicle speed is 1.2 mph (1.9 km/h) or less
Ignition is switched from ON/RUN to OFF
NOTE:For Keyless Enter ‘n Go™ equipped vehicles, the
engine will turn off and the ignition will change to
ACC position. After 30 minutes the ignition
switches to OFF automatically, unless the driver
turns the ignition OFF.
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 transmis -
sion
Driver door is ajar or if the driver 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 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).
4WD LOW
AutoPark will be disabled when operating the
vehicle in 4WD LOW.
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.
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.
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.

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.

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STARTING AND OPERATING149
(Continued)
3. The system will automatically engage the
starter to crank the engine. If the vehicle fails
to start, the starter will disengage automat-
ically 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.
COLD WEATHER PRECAUTIONS
Operation in ambient temperature below 32°F
(0°C) may require special considerations. The
following charts suggest these options:
Fuel Operating Range
NOTE:Use Ultra Low Sulfur Diesel (ULSD) Fuels
ONLY.

Fuel Operating Range Chart

*Number 1 ULSD Fuel should only be used where
extended arctic conditions 0°F (-18°C) exist.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build-up
may cause serious injury or death.
When leaving the vehicle, always make sure
the keyless ignition node is in the OFF posi -
tion, 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 chil -
dren to be in a vehicle unattended is
dangerous for a number of reasons. A child or
others could be seriously 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.
WARNING!
4

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STARTING AND OPERATING151
NOTE:Under certain conditions the Stop/Start system
may be temporarily disabled and the engine fan
will run after the engine is turned off to protect the
engine. 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 transmis -
sion 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
automatically turn off.
Do Not Operate The Engine With Low Oil
Pressure
If the Low Oil Pressure Warning Light turns on while
driving, stop the vehicle and shut down the engine
as soon as possible. After the vehicle is safely
stopped, restart the engine and monitor the lamp. If the lamp is still illuminated, shut the engine off,
contact an authorized dealer, and do not operate
the vehicle until the cause is corrected. If the lamp
is no longer illuminated, the engine can be
operated, but should be taken to an authorized
dealer as soon as possible for further inspection.
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.
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
see Ú page 424.
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.
4

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152STARTING AND OPERATING
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 interpreted 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
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 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 Úpage 424. 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.
Parking Brake Lever

When the parking brake is applied with the ignition
switch ON, the Brake Warning Light in the
instrument cluster will illuminate.
NOTE:
When the parking brake is applied and the auto -
matic transmission is placed in gear, the Brake
Warning Light will flash. If vehicle speed is
detected, a chime will sound to alert the driver.
Fully release the parking brake before
attempting to move the vehicle.
This light only shows that the parking brake is
applied. It does not show the degree of brake
application.
CAUTION!
Never use Non-Detergent Oil or Straight Mineral
Oil in the engine or damage may result.

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156STARTING AND OPERATING
(Continued)
IGNITION PARK INTERLOCK
This vehicle is equipped with an Ignition Park
Interlock system 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.
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 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 indi -
cator solidly indicates PARK (P) without
blinking. Ensure that the vehicle is completely
stopped, and the PARK position is properly
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
something. Only shift into gear when the
engine is idling normally and your foot is firmly
pressing the brake pedal.
WARNING!
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 transmis -
sion is locked in PARK, securing the vehicle
against unwanted movement.
When exiting the vehicle, always make sure
the ignition 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 chil -
dren to be in a vehicle unattended is
dangerous for a number of reasons. A child or
others could be seriously or fatally injured.
Children should be warned not to touch the
parking brake, brake pedal or the transmis -
sion 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!
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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158STARTING AND OPERATING
(Continued)
(Continued)
PARK (P)
This range supplements the parking brake by
locking the transmission. The engine can be
started in this range. Never attempt to use PARK
while the vehicle is in motion. Apply the parking
brake when exiting the vehicle in this range.
When parking on a hill, apply the parking brake
before shifting the transmission to PARK. As an
added precaution, turn the front wheels toward the
curb on a downhill grade and away from the curb
on an uphill grade.
When exiting the vehicle, always:
Apply the parking brake
Shift the transmission into PARK
Turn the ignition off
Remove the key fob from the vehicle
NOTE:On four-wheel drive vehicles, be sure that the
transfer case is in a drive position.
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 transmission 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 indi
-
cator solidly indicates PARK (P) without
blinking. Ensure that the vehicle is completely
stopped, and the PARK position is properly
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
something. Only shift into gear when the
engine is idling normally and your foot is firmly
pressing the brake pedal.
WARNING!
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 transmis -
sion is locked in PARK, securing the vehicle
against unwanted movement.
When exiting the vehicle, always make sure
the ignition 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 chil -
dren to be in a vehicle unattended is
dangerous for a number of reasons. A child or
others could be seriously or fatally injured.
Children should be warned not to touch the
parking brake, brake pedal or the transmis -
sion 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!

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