2021 JEEP WRANGLER check engine

Checking Oil Level — Gasoline Engine
To ensure proper lubrication of your vehicle's
engine, the engine oil must be maintained at
the correct level. The engine oil level should
be checked five minutes after a warmed up
engine has been shut off.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil
level readings. Always maintain the oil level
within the SAFE zone on the dipstick. Adding
1 quart (0.95 liters) of oil when the reading is
at the bottom of the crosshatch zone will
result in a reading at the top of the cross-
hatch zone on these engines.
CAUTION!
Overfilling or underfilling the crankcase
will cause aeration or loss of oil pressure.
This could damage your engine.
Checking Oil Level — Diesel Engine
To assure proper engine lubrication, the en-
gine oil must be maintained at the correct
level. Check the oil level at regular intervals,
such as every fuel stop.For vehicles equipped with a Diesel Particu-
late Filter (DPF), it is acceptable to have an
oil level up to 3/8 inch (10 mm) above the
MAX line. Beyond 3/8 inch (10 mm) it is
recommended to change the oil.
The best time to check the engine oil level is
about five minutes after a fully warmed en-
gine is shut off.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil
level readings. Maintain the oil level between
the MIN and MAX markings on the dipstick.
Adding 1 U.S. Quart (0.95 L) of oil when the
reading is at the MIN mark will result in a
MAX reading on these engines.
Cooling System
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
WARNING!
system pressure cap when the radiator
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 auto-
matically 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 ignition to the OFF mode. The
fan is temperature controlled and can
start at any time the ignition is in the ON
mode.
Engine Coolant Checks
Check the engine coolant (antifreeze) protec-
tion every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant (antifreeze) is dirty or rusty in
appearance, the system should be drained,
flushed and refilled with fresh engine coolant
(antifreeze). Check the front of the A/C con-
denser (if equipped) or radiator for any accu-
mulation of bugs, leaves, etc. If dirty, clean
SERVICING AND MAINTENANCE
182

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 en-
tire system for leaks. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.
Adding Washer Fluid
The fluid reservoir for the windshield washers
and the rear window washer (if equipped) is
shared. 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 radia-
tor 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 solu-
tion or mixture that meets or exceeds the
temperature range of your climate. This rat-
ing information can be found on most washer
fluid containers.
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.
Brake System
In order to assure brake system performance,
all brake system components should be in-
spected periodically. Refer to the “Mainte-
nance Plan” in this section for the proper
maintenance intervals.
WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your
foot resting or riding on the brake pedal
WARNING!
can result in abnormally high brake tem-
peratures, excessive lining wear, and pos-
sible brake damage. You would not have
your full braking capacity in an emergency.
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 cylin-
der 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 sys-
tem for leaks.
Refer to “Fluids And Lubricants” in “Techni-
cal Specifications” for further information.
183

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 per-
formance. The proper type of brake fluid
for your vehicle is also identified on the
original factory installed hydraulic mas-
ter 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 cylin-
der 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 fail-
ure. This could result in a collision.
• Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot en-
gine parts, causing the brake fluid to
WARNING!
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
contaminate the brake fluid. Brake seal
components could be damaged, causing
partial or complete brake failure. This
could result in a collision.
Manual Transmission
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.
Automatic Transmission
Fluid Level Check — Gasoline Engine
It is best to check the fluid level when the
transmission is at normal operating tempera-
ture (approximately 180°F/82°C). This oc-
curs after at least 15 miles (25 km) of driv-
ing. At normal operating temperature, the
fluid cannot be held comfortably between the
fingertips.
Use the following procedure to check the
transmission fluid level properly:
1. Park the vehicle on level ground.
2. Remove the engine cover by pulling it up
off the mounting studs (two in the front
and two in the rear).
3. Run the engine at normal idle speed for at
least 60 seconds, and leave the engine
running for the rest of this procedure.
4. Fully apply the parking brake, and press
the brake pedal.
SERVICING AND MAINTENANCE
184

5. Place the gear selector momentarily into
each gear position (allowing time for the
transmission to fully engage in each posi-
tion), ending with the transmission in
PARK.
6. Remove the dipstick, wipe it clean and
reinsert it until seated.
7. Remove the dipstick again and note the
fluid level on both sides. The fluid level
reading is only valid if there is a solid
coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be
full of fluid if the actual level is at or above
the hole. The fluid level should be be-
tween the HOT (upper) reference holes on
the dipstick at normal operating tempera-
ture. If the fluid level is low, add fluid
through the dipstick tube to bring it to the
proper level.Do not overfill.Use ONLY the
specified fluid (refer to "Fluids And Lubri-
cants" under “Technical Specifications”
for fluid specifications). After adding any
quantity of oil through the dipstick tube,
wait a minimum of two minutes for the oil
to fully drain into the transmission before
rechecking the fluid level.NOTE:
• The holes in the dipstick will be full of
fluid if the actual level is at or above the
hole.
• If it is necessary to check the transmis-
sion below the operating temperature,
the fluid level should be between the
two COLD (lower) holes on the dipstick
with the fluid at approximately 80°F
(27°C). If the fluid level is correctly
established at 80° F (27°C), it should
be between the HOT (upper) reference
holes when the transmission reaches
180° F (82°C). Remember it is best to
check the level at the normal operating
temperature.
CAUTION!
If the fluid temperature is below 50°F
(10°C) it may not register on the dipstick.
Do not add fluid until the temperature is
elevated enough to produce an accurate
reading. Run the engine at idle, in PARK,
to warm the fluid.8. Reinstall the engine cover and snap it
down securely onto the four mounting
studs.
9. Check for leaks. Release the parking
brake.
NOTE:
To prevent dirt and water from entering the
transmission after checking or replenishing
fluid, make sure that the dipstick cap is
properly reseated. It is normal for the dipstick
cap to spring back slightly from its fully
seated position, as long as its seal remains
engaged in the dipstick tube.
Fluid Level Check — 2.8L Turbo Diesel
Engine
The fluid level is preset at the factory and
does not require adjustment under normal
operating conditions. Routine fluid level
checks are not required, therefore the trans-
mission filler tube is capped and no dipstick
is provided. An authorized dealer can check
your transmission fluid level using a special
service dipstick.
185

After 25 miles (40 km), check the lug nut/
bolt torque to be sure that all the lug nuts/
bolts are properly seated against the wheel.
WARNING!
To avoid the risk of forcing the vehicle off
the jack, do not tighten the lug nuts fully
until the vehicle has been lowered. Failure
to follow this warning may result in per-
sonal injury.
FUEL REQUIREMENTS —
GASOLINE ENGINES
This engine is designed to meet all emissions
regulations and provide excellent fuel
economy and performance when using high
quality unleaded gasoline with a minimum
research octane rating (RON) of 91.
Light spark knock at low engine speeds is not
harmful to your engine. However, continued
heavy spark knock at high speeds can cause
damage, and immediate service is required.
Poor quality gasoline can cause problems
such as hard starting, stalling, and hesita-
tions. If you experience these symptoms, try
another brand of gasoline before considering
service for the vehicle.
Ethanol
The manufacturer recommends that your ve-
hicle be operated on fuel containing no more
than 15% ethanol. Purchasing your fuel from
a reputable supplier may reduce the risk of
exceeding this 15% limit and/or of receiving
fuel with abnormal properties. It should also
be noted that an increase in fuel consump-tion should be expected when using ethanol-
blended fuels, due to the lower energy con-
tent of ethanol. Problems that result from
using methanol/gasoline or E-85 ethanol
blends are not the responsibility of the
manufacturer.
CAUTION!
Use of fuel with Ethanol content higher
than 15% may result in engine malfunc-
tion, starting and operating difficulties,
and materials degradation. These adverse
effects could result in permanent damage
to your vehicle.
FUEL REQUIREMENTS —
DIESEL ENGINES
Use Premium Quality Diesel fuels with a
Cetane rating of 50 or higher, and meeting
the EN590 standard are highly recom-
mended. See your authorized dealer for fur-
ther information regarding fuels available in
your area.
Torque Patterns
209

Accessories..................212
Mopar...................212
Adding Fuel.................139
AirBag .....................93
Advance Front Air Bag.........93
Air Bag Operation.............94
Air Bag Warning Light..........92
Enhanced Accident Response . .98, 168
Event Data Recorder (EDR)......168
Front Air Bag...............93
If A Deployment Occurs.........97
Knee Impact Bolsters..........95
Maintaining Your Air Bag System . . .98
Transporting Pets............112
Air Bag Light............58, 92, 113
Air Bag Maintenance.............98
Air Conditioner Maintenance.......186
Air Conditioning Filter.........38, 187
Air Conditioning, Operating Tips......37
Air Conditioning Refrigerant. . . .186, 187
Air Conditioning System.......37, 186
Air Pressure, Tires..............193
Alarm (Security Alarm).........18, 61
Alterations/Modifications, Vehicle......4
Antifreeze (Engine Coolant)........210Anti-Lock Brake System (ABS).......68
Anti-Lock Warning Light...........61
Arming System (Security Alarm)......18
Assist, Hill Start................70
Audio Jack...............219, 226
Audio Settings................218
Automatic Headlights............29
Automatic Oil Change Indicator......58
Automatic Temperature Control (ATC) . . .37
Automatic Transmission..........127
Fluid Level Check...........184
Fluid Type................211
Autostick...................128
Axle Fluid...................211
Axle Lock...................132
Battery..................60, 186
Charging System Light.........60
Belts, Seat
.................
.113
Brake Assist System.............69
Brake Control System, Electronic.....69
Brake Fluid..............183, 211
Brake System................183
Fluid Check...............183
Master Cylinder.............183Parking..................121
Brake/Transmission Interlock.......127
Bulb Replacement..........146, 147
Bulbs, Light.................114
Capacities, Fluid..............210
Caps, Filler
Fuel....................139
Oil (Engine)...............180
Carbon Monoxide Warning.........112
Car Washes..................202
CD (Compact Disc) Player.........218
Center High Mounted Stop Light.....149
Chains, Tire..................200
Changing A Flat Tire.........154, 192
Checking Your Vehicle For Safety. . . .112
Checks, Safety................112
Child Restraints
How To Stow An Unused ALR Seat
Belt....................110
Cleaning
Wheels..................199
Climate Control................33
Manual...................33
Clock Setting.............218, 221
INDEX
259

Cold Weather Operation..........117
Compact Spare Tire.............198
Connector
UCI ....................233
Universal Consumer Interface
(UCI)...................233
Cooling System...............182
Coolant Capacity............210
Inspection................182
Selection Of Coolant (Antifreeze) . .210
Customer Assistance............242
Daytime Running Lights...........29
Dealer Service................189
Defroster, Windshield............113
Delay (Intermittent) Wipers.........31
Diagnostic System, Onboard........64
Diesel Engine Maintenance........175
Diesel Fuel..................209
Diesel Fuel Requirements.........209
Dimmer Switch, Headlight.........29
Dipsticks
Oil (Engine)...............182
Disabled Vehicle Towing..........165
Disarming, Security System.........18
Doors......................19Driver's Seat Back Tilt............21
Electronic Brake Control System......69
Anti-Lock Brake System........68
Electronic Roll Mitigation.......75
Traction Control System........71
Electronic Speed Control (Cruise
Control)..................136
Electronic Stability Control (ESC).....71
Electronic Throttle Control Warning
Light.....................60
Emergency Brake..............121
Emergency, In Case Of
Jacking..............154, 192
Jump Starting..............160
Engine.....................180
Break-In Recommendations.....121
Compartment...........180, 181
Compartment Identification . .180, 181
Cooling.................
.182
Exhaust Gas Caution..........112
Fails To Start...............118
Flooded, Starting............118
Fuel Requirements...........210
Jump Starting..............160
Oil .....................210
Oil Change Interval...........58Oil Filler Cap..............180
Oil Selection..............210
Overheating...............163
Starting.................117
Enhanced Accident Response
Feature................98, 168
Exhaust Gas Caution............112
Exhaust System...............112
Exterior Lights.............28, 114
Fabric Care..................203
Fabric Top..................203
Filters
Air Conditioning..........38, 187
Flashers
Hazard Warning.............146
Turn Signal......64, 114, 148, 149
Flash-To-Pass.................29
Flooded Engine Starting..........118
Fluid, Brake.................211
Fluid Capacities...............210
Fluid Leaks..................114
Fluid Level Checks
Brake...................183
Engine Oil................182
Manual Transmission.........184
Fluids And Lubricants...........210
INDEX
260

AirBag .............58, 92, 113
Automatic Headlights..........29
Back-Up.................149
Brake Assist Warning..........75
Bulb Replacement.......146, 147
Center Mounted Stop.........149
Cruise...................64
Daytime Running............29
Dimmer Switch, Headlight.......29
Exterior..................114
Fog .................29, 148
Hazard Warning Flasher........146
Headlight Leveling............30
Headlights.............28, 147
Headlight Switch.............28
High Beam................29
High Beam/Low Beam Select.....29
Hill Descent Control Indicator.....76
Instrument Cluster............28
Malfunction Indicator
(Check Engine)..............61
Passing..................29
Rear Fog.................148
Rear Servicing.............149
Rear Tail Lamps............149
Seat Belt Reminder...........60
Security Alarm..............61Service..............146, 147
Side Marker...............149
Tire Pressure Monitoring (TPMS) . . .62
Traction Control.............75
Turn Signal . . .29, 64, 114, 148, 149
Warning (Instrument Cluster
Description)................64
Locking Axle.................132
Lug Nuts...................208
Maintenance Free Battery.........186
Maintenance Schedule.......170, 175
Diesel..................175
Malfunction Indicator Light
(Check Engine)...............61
Manual Transmission........123, 184
Fluid Level Check...........184
Lubricant Selection..........211
Shift Speeds.............
.124
Media Center Radio.............220
Memory Feature (Memory Seat)......21
Memory Seat..................21
Memory Seats And Radio..........21
Mirrors.....................28
Heated...................28
Modifications/Alterations, Vehicle......4
Monitor, Tire Pressure System.......77Mopar.....................212
Mopar Accessories.............212
Navigation..................229
Navigation System (Uconnect GPS) . . .229
Navigation Voice Prompt Volume.....229
New Vehicle Break-In Period.......121
Occupant Restraints.............84
Octane Rating, Gasoline (Fuel)......209
Oil Change Indicator..........58, 176
Oil Change Indicator, Reset.....58, 176
Oil, Engine
Capacity.................210
Change Interval..............58
Dipstick.................182
Pressure Warning Light.........60
Recommendation...........210
Viscosity.................210
Oil Pressure Light...............60
Onboard Diagnostic System.........64
Operating Precautions............64
Operator Manual (Owner's Manual).....4
Outlet
Power...................52
Overheating, Engine............163
INDEX
262