2021 JEEP WRANGLER ESP

• Driving on a significantly under-inflated tire
causes the tire to overheat and can lead to
tire failure. Under-inflation also reduces
fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping
ability.
• The TPMS is not a substitute for proper tire
maintenance, and it is the driver’s respon-
sibility to maintain correct tire pressure,
even if under-inflation has not reached the
level to trigger illumination of the “Tire
Pressure Monitoring Telltale Light.”
• Seasonal temperature changes will affect
tire pressure, and the TPMS will monitor
the actual tire pressure in the tire.
Base System
The Tire Pressure Monitor System (TPMS)
uses wireless technology with wheel rim-
mounted electronic sensors to monitor tire
pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire
pressure readings to the Receiver Module.NOTE:
It is particularly important for you to check
the tire pressure in all of your tires regularly
and to maintain the proper pressure.
The Tire Pressure Monitor System (TPMS)
consists of the following components:
• Receiver Module
• Four Tire Pressure Monitoring Sensors
• Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in
the spare wheel if the vehicle is equipped
with a matching full size spare wheel and tire
assembly. The matching full size spare tire
can be used in place of any of the four road
tires. A low spare tire will not cause the “Tire
Pressure Monitoring Telltale Light” to illumi-
nate or the chime to sound while stowed in
the spare location.
The “Tire Pressure Monitoring Tell-
tale Light” will illuminate in the in-
strument cluster, a “LOW TIRE
PRESSURE” message will display in the in-
strument cluster, and an audible chime will
be activated when one or more of the four
active road tire pressures are low. Should thisoccur, you should stop as soon as possible,
check the inflation pressure of each tire on
your vehicle, and inflate each tire to the
vehicle's recommended cold placard pres-
sure value. The system will automatically
update and the “Tire Pressure Monitoring
Telltale Light” will extinguish once the up-
dated tire pressures have been received. The
vehicle may need to be driven for up to
10 minutes above 15 mph (24 km/h) to
receive this information
The “Tire Pressure Monitoring Telltale Light”
will flash on and off for 75 seconds, and will
remain on solid when a system fault is de-
tected. The system fault will also sound a
chime. If the ignition key is cycled, this
sequence will repeat, providing the system
fault still exists. The “Tire Pressure Monitor-
ing Telltale Light” will turn off when the fault
condition no longer exists. A system fault can
occur by any of the following scenarios:
1. Jamming due to electronic devices or driv-
ing next to facilities emitting the same
Radio Frequencies as the TPM sensors.
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properly, or if items are positioned in the area
where the SAB inflates. Children are at an
even greater risk of injury from a deploying air
bag.
WARNING!
Do not use accessory seat covers or place
objects between you and the Side Air
Bags; the performance could be adversely
affected and/or objects could be pushed
into you, causing serious injury.
Side Impacts
The Side Air Bags are designed to activate in
certain side impacts. The Occupant Restraint
Controller (ORC) determines whether the de-
ployment of the Side Air Bags in a particular
impact event is appropriate, based on the
severity and type of collision. The side impact
sensors aid the ORC in determining the ap-
propriate response to impact events. The
system is calibrated to deploy the Side Air
Bags on the impact side of the vehicle during
impacts that require Side Air Bag occupant
protection. In side impacts, the Side Air Bags
deploy independently; a left side impact de-ploys the left Side Air Bags only and a right-
side impact deploys the right Side Air Bags
only. Vehicle damage by itself is not a good
indicator of whether or not Side Air Bags
should have deployed.
The Side Air Bags will not deploy in all side
collisions, including some collisions at cer-
tain angles, or some side collisions that do
not impact the area of the passenger com-
partment. The Side Air Bags may deploy
during angled or offset frontal collisions
where the front air bags deploy.
Side Air Bags are a supplement to the seat
belt restraint system. Side Air Bags deploy in
less time than it takes to blink your eyes.
WARNING!
• Occupants, including children, who are
up against or very close to Side Air Bags
can be seriously injured or killed. Occu-
pants, including children, should never
lean on or sleep against the door, side
windows, or area where the side air bags
inflate, even if they are in an infant or
child restraint.
WARNING!
• Seat belts (and child restraints where
appropriate) are necessary for your pro-
tection in all collisions. They also help
keep you in position, away from an in-
flating Side Air Bag. To get the best
protection from the Side Air Bags, occu-
pants must wear their seat belts properly
and sit upright with their backs against
the seats. Children must be properly
restrained in a child restraint or booster
seat that is appropriate for the size of the
child.
WARNING!
• Side Air Bags need room to inflate. Do
not lean against the door or window. Sit
upright in the center of the seat.
• Being too close to the Side Air Bags
during deployment could cause you to
be severely injured or killed.
• Relying on the Side Air Bags alone could
lead to more severe injuries in a colli-
sion. The Side Air Bags work with your
seat belt to restrain you properly. In
SAFETY
96

NOTE:
• Air bag covers may not be obvious in the
interior trim, but they will open during air
bag deployment.
• After any collision, the vehicle should be
taken to an authorized dealer immediately.
Enhanced Accident Response System
In the event of an impact, if the communica-
tion network remains intact, and the power
remains intact, depending on the nature of
the event, the ORC will determine whether to
have the Enhanced Accident Response Sys-
tem perform the following functions:
• Cut off fuel to the engine.
• Flash hazard lights as long as the battery
has power or until the hazard light button is
pressed. The hazard lights can be deacti-
vated by pressing the hazard light button.
• Turn on the interior lights, which remain on
as long as the battery has power.
• Unlock the power door locks.
Enhanced Accident Response System Reset
Procedure
In order to reset the Enhanced Accident Re-
sponse System functions after an event, the
ignition switch must be changed from igni-
tion START or ON/RUN to ignition OFF. Care-
fully check the vehicle for fuel leaks in the
engine compartment and on the ground near
the engine compartment and fuel tank before
resetting the system and starting the engine.
Maintaining Your Air Bag System
WARNING!
• Modifications to any part of the air bag
system could cause it to fail when you
need it. You could be injured if the air
bag system is not there to protect you.
Do not modify the components or wiring,
including adding any kind of badges or
stickers to the steering wheel hub trim
cover or the upper right side of the
instrument panel. Do not modify the
front bumper, vehicle body structure, or
add aftermarket side steps or running
boards.
WARNING!
• It is dangerous to try to repair any part of
the air bag system yourself. Be sure to
tell anyone who works on your vehicle
that it has an air bag system.
• Do not attempt to modify any part of your
air bag system. The air bag may inflate
accidentally or may not function prop-
erly if modifications are made. Take your
vehicle to an authorized dealer for any
air bag system service. If your seat, in-
cluding your trim cover and cushion,
needs to be serviced in any way (includ-
ing removal or loosening/tightening of
seat attachment bolts), take the vehicle
to your authorized dealer. Only manufac-
turer approved seat accessories may be
used. If it is necessary to modify the air
bag system for persons with disabilities,
contact your authorized dealer.
Event Data Recorder (EDR)
This vehicle is equipped with an event data
recorder (EDR). The main purpose of an EDR
is to record, in certain crash or near crash-
like situations, such as an air bag deployment
SAFETY
98

After Starting
The idle speed is controlled automatically,
and it will decrease as the engine warms up.
Normal Starting — Diesel Engine
1. The gear selector must be in the NEU-
TRAL or PARK position before you can
start the engine.
2. Turn the ignition key to the ON position.
3. Watch for the “Wait To Start Light” in the
instrument cluster. Refer to “Instrument
Cluster” in “Getting To Know Your Instru-
ment Panel” for further review. It will glow
for two to ten seconds or more, depending
on engine temperature. When the “Wait
To Start Light” goes out, the engine is
ready to start.
4. Tip Start Feature (Automatic Transmission
Only)
Do notpress the accelerator. Turn the
ignition key to the START position and
then release it. The starter motor will
continue to run, and it will automatically
disengage when the engine is running. If
the engine fails to start, the starter willdisengage automatically in 25 seconds.
If this occurs, turn the ignition switch to
the LOCK position, wait 25 to 30 sec-
onds, then repeat the “Normal Starting”
procedure.
NOTE:
The starter motor may run up to 30 sec-
onds in very cold conditions until the
engine is started. The starter can be dis-
engaged by turning the ignition key to
the OFF position, if required.
5. Without Tip Start Feature (Manual Trans-
mission Only)
Turn the ignition switch to the START
position and release when the engine
starts. If the engine fails to start within
10 seconds, turn the ignition switch to
the LOCK position, wait 10 to 15 sec-
onds, then repeat the “Normal Starting”
procedure.
6. After the engine starts, allow it to idle for
approximately 30 seconds before driving.
This allows oil to circulate and lubricate
the turbocharger.
Diesel Engine Warm-Up
Avoid full throttle operation when the engine
is cold. When starting a cold engine, bring the
engine up to operating speed slowly to allow
the oil pressure to stabilize as the engine
warms up.
NOTE:
High-speed, no-load running of a cold engine
can result in excessive white smoke and poor
engine performance. No-load engine speeds
should be kept under 1,200 rpm during the
warm-up period, especially in cold, ambient
temperature conditions.
If temperatures are below 32°F (0°C), oper-
ate the engine at moderate speeds for five
minutes before full loads are applied.
Diesel Engine Idling — In Cold Weather
Avoid prolonged idling in ambient tempera-
tures below 0°F (-18°C). Long periods of
idling may be harmful to your engine because
combustion chamber temperatures can drop
so low that the fuel may not burn completely.
Incomplete combustion allows carbon and
varnish to form on piston rings and injector
119

nozzles. Also, the unburned fuel can enter
the crankcase, diluting the oil and causing
rapid wear to the engine.
Stopping the Engine
The following chart should be used as a guide
in determining the amount of engine idle
time required to sufficiently cool down the
turbocharger before shut down, depending
upon the type of driving and the amount of
cargo.Before turning off your turbo diesel engine,
always allow the engine to return to normal idle
speed and run for several seconds. This assures
proper lubrication of the turbocharger. This is
particularly necessary after any period of hard
driving.
Idle the engine a few minutes before routine
shutdown. After full load operation, idle the
engine three to five minutes before shutting itdown. This idle period will allow the lubricat-
ing oil and coolant to carry excess heat away
from the combustion chamber, bearings, in-
ternal components, and turbocharger. This is
especially important for turbocharged,
charge air cooled engines.
TURBOCHARGER "COOL DOWN" CHART
Driving
ConditionsLoad Turbocharger
TemperatureIdle Time (In Minutes)
Before Shut Down
Stop & Go Empty Cool Less than 1
Stop & Go Medium Warm 1
Highway Speeds Medium Warm 2
City Traffic Max. GCWR Warm 3
Highway Speeds Max. GCWR Warm 4
Uphill Grade Max. GCWR Hot 5
STARTING AND OPERATING
120

MANUAL TRANSMISSION —
IF EQUIPPED
WARNING!
You or others could be injured if you leave
the vehicle unattended without having the
parking brake fully applied. The parking
brake should always be applied when the
driver is not in the vehicle, especially on an
incline.
CAUTION!
Never drive with your foot resting on the
clutch pedal, or attempt to hold the ve-
hicle on a hill with the clutch pedal par-
CAUTION!
tially engaged, as this will cause abnormal
wear on the clutch.
NOTE:
During cold weather, you may experience
increased effort in shifting until the transmis-
sion fluid warms up. This is normal.
Shifting
Fully press the clutch pedal before shifting
gears. As you release the clutch pedal, lightly
press the accelerator pedal.
You should always use first gear when starting
from a standing position.
NOTE:
A certain amount of noise from the transmis-
sion is normal. This noise can be most notice-
able when the vehicle is idling in NEUTRAL
with the clutch engaged (clutch pedal re-
leased), but it may also be heard when driv-
ing. The noise may also be more noticeable
when the transmission is warm. This noise is
normal and is not an indication of a problem
with your clutch or transmission.
Shift Pattern
123

NOTE:
Shifting into or out of 4L is possible with the
vehicle completely stopped; however, diffi-
culty may occur due to the mating teeth not
being properly aligned. Several attempts may
be required for clutch teeth alignment and
shift completion to occur. The preferred
method is with the vehicle rolling at 2 to
3 mph (3 to 5 km/h). Avoid attempting to
engage or disengage 4L with the vehicle
moving faster than 2 to 3 mph (3 to 5 km/h).
WARNING!
Failure to engage a transfer case position
completely can cause transfer case dam-
age or loss of power and vehicle control.
You could have a collision. Do not drive the
vehicle unless the transfer case is fully
engaged.
Trac-Lok Rear Axle — If Equipped
The Trac-Lok rear axle provides a constant
driving force to both rear wheels and reduces
wheel spin caused by the loss of traction at
one driving wheel. If traction differs between
the two rear wheels, the differential auto-
matically proportions the usable torque by
providing more torque to the wheel that has
traction.
Trac-Lok is especially helpful during slippery
driving conditions. With both rear wheels on a
slippery surface, a slight application of the
accelerator will supply maximum traction.
WARNING!
On vehicles equipped with a limited-slip
differential, never run the engine with one
rear wheel off the ground. The vehicle may
drive through the rear wheel remaining on
the ground and cause you to lose control of
your vehicle.
Axle Lock (Tru-Lok) — Rubicon Models
The AXLE LOCK switch is located on the
instrument panel (to the left of the steering
column).
This feature will only activate when the fol-
lowing conditions are met:
• Key in ignition, vehicle in 4L (Low) range.
• Vehicle speed should be 10 mph (16 km/h)
or less.
Axle Lock Switch
STARTING AND OPERATING
132

IN CASE OF EMERGENCY
HAZARD WARNING
FLASHERS................146
BULB REPLACEMENT........146
Replacement Bulbs............146
Bulb Replacement.............147
FUSES...................149
General Information.............150
Totally Integrated Power Module.....150
JACKING AND TIRE
CHANGING................154
Jack/Spare Tire Stowage..........154
Preparations For Jacking.........154
Jacking Instructions............155
Declaration Of Conformance.......157
Jack Usage Precautions..........160
JUMP STARTING............160
Preparations For Jump Start........161
Jump Starting Procedure..........162
IF YOUR ENGINE OVERHEATS . .163GEAR SELECTOR OVERRIDE . . .164
FREEING A STUCK VEHICLE . . .164
TOWING A DISABLED
VEHICLE..................165
Without The Ignition Key..........166
Four–Wheel Drive Models.........166
Tow Eye Usage................167
ENHANCED ACCIDENT RESPONSE
SYSTEM (EARS).............168
EVENT DATA RECORDER
(EDR)....................168
IN CASE OF EMERGENCY
145