2023 JEEP GLADIATOR check engine

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.
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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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170STARTING AND OPERATING
The Stop/Start feature is enabled after every
normal customer engine start. At that time, the
system will go into STOP/START READY.
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 instrument cluster display
within the Stop/Start section Ú page 121.
The vehicle must be completely stopped.
The gear selector must be in a forward gear and
the brake pedal pressed.
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.
POSSIBLE REASONS THE ENGINE DOES
N
OT 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 is set to MAX A/C
Engine has not reached normal operating
temperature
Engine or exhaust temperature is too high
The transmission is not in a forward gear
Hood is open
Transfer case is in 4L or N (Neutral)
Brake pedal is not pressed with sufficient pres -
sure
Accelerator pedal input
Vehicle speed threshold has not been achieved
from previous Autostop
Steering angle is beyond threshold
ACC is on and speed is set
Vehicle is at high altitude
System fault is 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.
TO START THE ENGINE WHILE IN
A
UTOSTOP MODE
While in a forward gear, the engine will start when
the brake pedal is released or the throttle pedal is
pressed. The transmission will automatically
re-engage upon engine restart.
Conditions That Will Cause The Engine To Start
Automatically While In Autostop Mode:

The transmission selector is moved out of DRIVE

To maintain cabin temperature comfort
Actual cabin temperature is significantly
different than temperature set on Auto HVAC
HVAC is set to full defrost mode
HVAC system temperature or fan speed is
manually adjusted
Battery voltage drops too low
Stop/Start OFF switch is pushed
A Stop/Start system error occurs
Stop/Start Autostop Active time exceeds five
minutes
Transfer case is in 4L or N (Neutral)
Steering wheel is turned beyond threshold

23_JT_OM_EN_USC_t.book Page 170

STARTING AND OPERATING171
TO MANUALLY TURN OFF THE STOP/
S
TART SYSTEM

Stop/Start OFF Switch

Push the Stop/Start OFF switch (located on the
switch bank). The light on the switch will illuminate.
The “Stop/Start OFF” message will appear in
instrument cluster display within the Stop/Start
section, and the autostop function will be disabled
Ú page 121.
NOTE:The Stop/Start system will reset itself back to an
ON condition every time the ignition is turned off
and back on.
TO MANUALLY TURN ON THE STOP/
S
TART SYSTEM
Push the Stop/Start Off switch (located on the
switch bank). The light on the switch will turn off.
SYSTEM MALFUNCTION
If there is a malfunction in the Stop/Start system,
the system will not shut down the engine. A
“SERVICE STOP/START SYSTEM” message and a
yellow Stop/Start telltale will appear in the
instrument cluster display Ú page 121.
If the “SERVICE STOP/START SYSTEM” message
appears in the instrument cluster display, have the
system checked by an authorized dealer.
STOP/START SYSTEM — MANUAL
TRANSMISSION (IF EQUIPPED)
The Engine Stop/Start (ESS) function is developed
to reduce fuel consumption. The system will stop
the engine automatically during a vehicle stop if
the required conditions are met. Pressing the
clutch pedal will automatically restart the vehicle.
NOTE:It is recommended that the Stop/Start system be
disabled during off-road use. Secondary Battery
Your vehicle may be equipped with a secondary
battery used to power the Stop/Start system and
the 12 Volt vehicle electrical system. The
secondary battery is located behind the wheel well
for the front passenger wheel.

Battery Locations

1 — Primary Battery
2 — Secondary Battery
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172STARTING AND OPERATING
AUTOSTOP MODE
The Stop/Start feature is enabled after every
normal customer engine start. It will remain in
STOP/START NOT READY until you drive forward
with a vehicle speed greater than 5 mph (8 km/h).
At that time, the system will go into STOP/START
READY and if all other conditions are met, can go
into an STOP/START AUTOSTOP ACTIVE mode.
To Activate The STOP/START AUTOSTOP ACTIVE
Mode, The Following Must Occur:

The system must be in STOP/START READY
state. A STOP/START READY message will be
displayed in the instrument cluster
Ú
page 121.

Vehicle speed must be less than 2 mph
(3 km/h).
The gear selector must be in the NEUTRAL posi -
tion and the clutch pedal must be fully released. The engine will shut down,
the tachometer will fall
to the Stop/Start position, the STOP/START
AUTOSTOP ACTIVE message will appear, and the
heater/air conditioning (HVAC) air flow will be
reduced.
POSSIBLE REASONS THE ENGINE DOES
N
OT AUTOSTOP
Prior to engine shut down, the system will check
many safety and comfort conditions to see if they
are fulfilled. In following situations the engine will
not stop:
Driver’s seat belt is not buckled
Outside temperature is less than 10°F (–12°C)
or greater than 109°F (43°C)
Actual cabin temperature is significantly
different than temperature set on Auto HVAC
HVAC is set to full defrost mode
Engine has not reached normal operating
temperature
Battery is discharged
When driving in REVERSE
Hood is open
Transfer case is in 4L or N (Neutral)
Driver's seat is not occupied or driver door is
open
Vehicle is at high altitude
The vehicle is on a steep grade
Forward Gear is engaged
Steering angle is beyond threshold
System fault is present
HVAC is set to MAX A/C
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.
TO START THE ENGINE WHILE IN
A
UTOSTOP MODE
When the gear selector is in NEUTRAL, the engine
will start when the clutch pedal is pressed (does
not require complete/full pedal press). The vehicle
will go into STOP/START SYSTEM NOT READY
mode until the vehicle speed is greater than 5 mph
(8 km/h).
Conditions that will cause the engine to start
automatically while in STOP/START AUTOSTOP
ACTIVE mode, the engine will start automatically
when:
Actual cabin temperature is significantly
different than temperature set on Auto HVAC
HVAC is set to full defrost mode
Stop/Start Autostop Active time exceeds five
minutes
WARNING!
Vehicles with the Stop/Start system will be
equipped with two batteries. Both the main
and the supplemental batteries must be
disconnected to completely de-energize the
12 Volt electrical system.
Serious injury or death could result if you do
not disconnect both batteries. To learn how to
properly disconnect, see an authorized dealer.

23_JT_OM_EN_USC_t.book Page 172

STARTING AND OPERATING173
Battery voltage drops too low
Vehicle is moving faster than 5 mph (8 km/h)
Stop/Start OFF switch is pressed
Transfer case is in 4L or N (Neutral)
Steering wheel is turned beyond threshold (ESS
Models Only)
TO MANUALLY TURN OFF THE STOP/
S
TART SYSTEM

Stop/Start OFF Switch

Push the Stop/Start OFF switch (located on the
switch bank). The light on the switch will illuminate.
The “Stop/Start OFF” message will appear in
instrument cluster display within the Stop/Start
section, and the Autostop function will be disabled
Ú page 121.
NOTE:The Stop/Start system will reset itself back to an
ON condition every time the ignition is turned off
and back on.
TO MANUALLY TURN ON THE STOP/
S
TART SYSTEM
Push the Stop/Start Off switch (located on the
switch bank). The light on the switch will turn off.
SYSTEM MALFUNCTION
If there is a malfunction in the Stop/Start system,
the system will not shut down the engine. A
“SERVICE STOP/START SYSTEM” message and a
yellow Stop/Start telltale will appear in the
instrument cluster display Ú page 121.
If the “SERVICE STOP/START SYSTEM” message
appears in the instrument cluster display, have the
system checked by an authorized dealer.
CRUISE CONTROL SYSTEMS — IF EQUIPPED
Your vehicle may be equipped with the Cruise
Control system, or the Adaptive Cruise Control
(ACC) system:
Cruise Control will keep your vehicle at a
constant preset speed.
Adaptive Cruise Control (ACC) will adjust the
vehicle speed up to the preset speed to main -
tain a distance with the vehicle ahead.
NOTE:
In vehicles equipped with ACC, if ACC is not
enabled, Fixed Speed Cruise Control will not
detect vehicles directly ahead of you. Always be
aware of the feature selected.
Only one Cruise Control feature can operate at a
time. For example, if Fixed Speed Cruise Control
is enabled, Adaptive Cruise Control will be
unavailable, and vice versa.
CRUISE CONTROL
When engaged, the Cruise Control system takes
over accelerator operations at speeds greater than
20 mph (32 km/h).
The Cruise Control buttons are located on the right
side of the steering wheel.
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