service interval JEEP WRANGLER UNLIMITED 2021 Owner handbook (in English)

105
Air Bag Warning Light
The Occupant Restraint Controller
(ORC) monitors the readiness of the
electronic parts of the air bag
system whenever the ignition
switch is in the START or ON/RUN position.
If the ignition switch is in the OFF position or
in the ACC position, the air bag system is not
on and the air bags will not inflate.
The ORC contains a backup power supply
system that may deploy the air bag system
even if the battery loses power or it becomes
disconnected prior to deployment.
The ORC turns on the Air Bag Warning Light
in the instrument panel for approximately
four to eight seconds for a self-check when
the ignition switch is first in the ON/RUN
position. After the self-check, the Air Bag
Warning Light will turn off. If the ORC
detects a malfunction in any part of the
system, it turns on the Air Bag Warning
Light, either momentarily or continuously. A
single chime will sound to alert you if the
light comes on again after initial startup.
The ORC also includes diagnostics that will
illuminate the instrument panel Air Bag
Warning Light if a malfunction is detected that
could affect the air bag system. The diagnos
-
tics also record the nature of the malfunction.
While the air bag system is designed to be
maintenance free, if any of the following
occurs, have an authorized dealer service the
air bag system immediately.

The Air Bag Warning Light does not come on
during the four to eight seconds when the igni -
tion switch is first in the ON/RUN position.

The Air Bag Warning Light remains on
after the four to eight-second interval.
The Air Bag Warning Light comes on inter -
mittently or remains on while driving.
NOTE:
If the speedometer, tachometer, or any
engine related gauges are not working, the
Occupant Restraint Controller (ORC) may
also be disabled. In this condition the air
bags may not be ready to inflate for your
protection. Have an authorized dealer service
the air bag system immediately.
Redundant Air Bag Warning Light
If a fault with the Air Bag Warning
Light is detected, which could
affect the Supplemental Restraint
System (SRS), the Redundant Air
Bag Warning Light will illuminate on the
instrument panel. The Redundant Air Bag
Warning Light will stay on until the fault is
cleared. In addition, a single chime will
sound to alert you that the Redundant Air
Bag Warning Light has come on and a fault
has been detected. If the Redundant Air Bag
Warning Light comes on intermittently or
remains on while driving have an authorized
dealer service the vehicle immediately.
WARNING!
Ignoring the Air Bag Warning Light in your
instrument panel could mean you won’t
have the air bag system to protect you in a
collision. If the light does not come on as
a bulb check when the ignition is first
turned on, stays on after you start the
vehicle, or if it comes on as you drive, have
an authorized dealer service the air bag
system immediately.
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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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SERVICING AND MAINTENANCE
216
Severe Duty Conditions
Change the engine oil and engine oil filter at
every 4,500 miles (7,500 km) or 6 months
if using your vehicle under any of the
following severe duty conditions:
Stop and go driving.
Driving in dusty conditions.
Short trips of less than 10 miles (16 km).
Trailer towing.
Taxi, police, or delivery service (commer-
cial service).
Off-road or desert operation.
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 engine oil
replacement.
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.

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. Severe Operating Conditions can cause the
change oil message to illuminate as earlier than
specified. Have your vehicle serviced as soon
as possible, within the next 500 miles
(805 km).

NOTE:
The actual interval for changing engine oil
and replacing the engine oil filter depends
on the vehicle usage conditions, and is
signaled by the warning light or message
in the instrument panel. In any case, it
must never exceed 12,500 miles
(20,000 km) or 1 year
Flush and replace the engine coolant at
120 months or 150,000 miles (240,000 km)
whichever comes first.
The maximum mileage is 75,000 mi
(120,000 km). The belt must be replaced
every 5 years regardless of distance trav-
eled. The timing and accessory belts must be
changed every 37,500 miles (60,000 km) or
3 years for particularly demanding use
(dusty areas, severe weather conditions,
very low or very high temperatures for
extended periods, city driving, long periods
of idling). Under no circumstances should
these intervals be exceeded.
WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe-
tent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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SERVICING AND MAINTENANCE
220
(*) The actual interval for changing engine
oil and replacing the engine oil filter
depends on the vehicle usage conditions,
and is signaled by the warning light or
message in the instrument panel. In any
case, it must never exceed 12,500 miles
(20,000 km) or 1 year.
(**) The brake fluid interval is time based
only, mileage intervals do not apply.(***) The maximum mileage is 75,000 mi
(120,000 km). The belt must be replaced
every 5 years regardless of distance traveled.
The timing and accessory belts must be
changed every 37,500 miles (60,000 km) or
3 years for particularly demanding use (dusty
areas, severe weather conditions, very low or
very high temperatures for extended periods,
city driving, long periods of idling). Under no
circumstances should these intervals be
exceeded.
(°) Consumption of additive AdBlue®
(UREA) depends on the condition of use of
the vehicle and is indicated by LED and/or
message on the instrument panel. WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe-
tent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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SERVICING AND MAINTENANCE
230(Continued)
Coolant Checks
Check the engine and, intercooler (if
equipped) coolant (antifreeze) protection
every 12 months (before the onset of
freezing weather, where applicable). If the
engine and, intercooler (if equipped) is dirty
or rusty in appearance, the system should be
drained, flushed and refilled with fresh 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 and, intercooler (if
equipped) 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.
Brake System
In order to ensure brake system perfor
-
mance, all brake system components should
be inspected periodically. Refer to the
“Maintenance Plan” in this section for the
proper maintenance intervals.
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.
Refer to “Fluids And Lubricants” in “Tech -
nical Specifications” for further information.When working near the radiator cooling
fan, turn the ignition to the OFF mode.
The fan is temperature controlled and
can start at any time the ignition is in the
ON mode.
WARNING! (Continued)
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's recommended
brake fluid. Refer to “Fluids And Lubri -
cants” in “Technical Specifications” for
further information. 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.
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