2012 JEEP WRANGLER cooling

NOTE:There are steps that you can take to slow down
an impending overheat condition:
•If your air conditioner (A/C) is on, turn it off. The A/C
system adds heat to the engine cooling system and
turning the A/C off can help remove this heat.
•You can also turn the temperature control to maximum
heat, the mode control to floor and the blower control
to high. This allows the heater core to act as a
supplement to the radiator and aids in removing heat
from the engine 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 try to open a cooling system pressure
cap when the radiator or coolant bottle is hot.
JACKING AND TIRE CHANGING
WARNING!
•Do not attempt to change a tire on the side of the
vehicle close to moving traffic. Pull far enough off
the road to avoid the danger of being hit when
operating the jack or changing the wheel.
•Being under a jacked-up vehicle is dangerous. The
vehicle could slip off the jack and fall on you. You
could be crushed. Never put any part of your body
under a vehicle that is on a jack. If you need to get
under a raised vehicle, take it to a service center
where it can be raised on a lift.
•Never start or run the engine while the vehicle is
on a jack.
(Continued)
6
WHAT TO DO IN EMERGENCIES 493

Preparations For Jump-Start
The battery in your vehicle is located in the right rear of
the engine compartment, behind the Power Distribution
Center.WARNING!
•Take care to avoid the radiator cooling fan when-
ever the hood is raised. It can start anytime the
ignition switch is on. You can be injured by
moving fan blades.
•Remove any metal jewelry such as watch bands or
bracelets that might make an inadvertent electrical
contact. You could be seriously injured.
•Batteries contain sulfuric acid that can burn your
skin or eyes and generate hydrogen gas which is
flammable and explosive. Keep open flames or
sparks away from the battery.
1. Set the parking brake, shift the automatic transmission
into PARK (manual transmission in NEUTRAL) and turn
the ignition to LOCK.
2. Turn off the heater, radio, and all unnecessary electri-
cal accessories.
Positive Battery Post
502 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment — 3.6L ............. 513
 Onboard Diagnostic System — OBD II ...... 514
▫ Loose Fuel Filler Cap Message ........... 514
 Emissions Inspection And Maintenance
Programs ............................ 515
 Replacement Parts ..................... 516
 Dealer Service ........................ 517
 Maintenance Procedures ................. 517
▫ Engine Oil ......................... 518 ▫
Engine Oil Filter ..................... 520
▫ Engine Air Cleaner Filter ............... 520
▫ Maintenance-Free Battery .............. 521
▫ Air Conditioner Maintenance ............ 522
▫ Body Lubrication .................... 526
▫ Windshield Wiper Blades ............... 526
▫ Adding Washer Fluid ................. 527
▫ Exhaust System ..................... 527
▫ Cooling System ..................... 530
7

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 try to open a cooling system pressure
cap when the radiator or coolant bottle is hot.
Engine Coolant Checks
Check the engine coolant (antifreeze) protection 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 (anti-
freeze). Check the front of the A/C condenser (ifequipped) 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 con-
denser (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
entire system for leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
engine coolant (antifreeze) from the radiator drain cock.
If the cap is sealing properly, the engine coolant (anti-
freeze) will begin to drain from the coolant recovery
bottle. DO NOT REMOVE THE COOLANT PRESSURE
CAP WHEN THE COOLING SYSTEM IS HOT.
530 MAINTAINING YOUR VEHICLE

Cooling System – Drain, Flush, And Refill
If the engine coolant (antifreeze) is dirty and contains a
considerable amount of sediment, clean and flush with
reliable cooling system cleaner. Follow with a thorough
rinsing to remove all deposits and chemicals. Properly
dispose of the old engine coolant (antifreeze).
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
Selection Of Engine Coolant
Use only the manufacturer’s recommended engine cool-
ant (antifreeze). Refer to “Fluids, Lubricants, and Genu-
ine Parts” in “Maintaining Your Vehicle” for further
information.
CAUTION!
•Mixing of engine coolant (antifreeze) other than
the specified HOAT engine coolant (antifreeze)
may result in engine damage and may decrease
corrosion protection. If a non-HOAT engine cool-
ant (antifreeze) is introduced into the cooling
system in an emergency, it should be replaced with
the specified engine coolant (antifreeze) as soon as
possible.
•Do not use water alone or alcohol-based engine
coolant (antifreeze) products. Do not use addi-
tional rust inhibitors or antirust products, as they
may not be compatible with the antifreeze/engine
coolant (antifreeze) and may plug the radiator.
•This vehicle has not been designed for use with
Propylene Glycol based engine coolant (anti-
freeze). Use of Propylene Glycol base engine cool-
ant (antifreeze) is not recommended.
7
MAINTAINING YOUR VEHICLE 531

Adding Engine Coolant
Your vehicle has been built with an improved engine
coolant (antifreeze) that allows extended maintenance
intervals. This engine coolant (antifreeze) can be used up
to five years or 104,000 miles (169 000 km) before
replacement. To prevent reducing this extended mainte-
nance period, it is important that you use the same
engine coolant (antifreeze) throughout the life of your
vehicle.
Please review these recommendations for using Hybrid
Organic Additive Technology (HOAT) engine coolant
(antifreeze). When adding engine coolant (antifreeze):
•The manufacturer recommends using MOPAR
Antifreeze/Coolant 5 Year/100,000 Mile Formula
HOAT (Hybrid Organic Additive Technology) or
equivalent.
•Mix a minimum solution of 50% HOAT engine coolant
and distilled water. Use higher concentrations (not to
exceed 70%) if temperatures below 34°F (37°C) are
anticipated.
•Use only high purity water such as distilled or deion-
ized water when mixing the water/engine coolant
(antifreeze) solution. The use of lower quality water
will reduce the amount of corrosion protection in the
engine cooling system.
Please note that it is the owner’s responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE: Mixing engine coolant (antifreeze) types will
decrease the life of the engine coolant (antifreeze) and
will require more frequent coolant changes.
532 MAINTAINING YOUR VEHICLE

Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that engine coolant
(antifreeze) will return to the radiator from the coolant
reserve tank.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
The warning words DO NOT OPEN HOT on the
cooling system pressure cap are a safety precaution.
Never add engine coolant (antifreeze) when the en-
gine is overheated. Do not loosen or remove the cap
to cool an overheated engine. Heat causes pressure to
build up in the cooling system. To prevent scalding
or injury, do not remove the pressure cap while the
system is hot or under pressure.
Disposal Of Used Engine Coolant
Used ethylene glycol based engine coolant (antifreeze) is
a regulated substance requiring proper disposal. Check
with your local authorities to determine the disposal
rules for your community. To prevent ingestion by ani-
mals or children, do not store ethylene glycol based
engine coolant (antifreeze) in open containers or allow it
to remain in puddles on the ground. If ingested by a child
or pet, seek emergency assistance immediately. Clean up
any ground spills immediately.
Engine Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine idling, and warm to normal operating tempera-
ture, the level of the engine coolant (antifreeze) in the
bottle should be between the ranges indicated on the
bottle.
7
MAINTAINING YOUR VEHICLE 533

The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
engine coolant (antifreeze) freeze point or replacing en-
gine coolant (antifreeze). Advise your service attendant
of this. As long as the engine operating temperature is
satisfactory, the coolant bottle need only be checked once
a month.
When additional engine coolant (antifreeze) is needed to
maintain the proper level, it should be added to the
coolant bottle. Do not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles/
kilometers of operation, you may observe vapor coming
from the front of the engine compartment. This is nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot engine
coolant (antifreeze) to enter the radiator. If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
•Do not overfill the coolant bottle.
•Check the engine coolant (antifreeze) freeze point in
the radiator and in the coolant recovery bottle. If
engine coolant (antifreeze) needs to be added, the
contents of the coolant recovery bottle must also be
protected against freezing.
•If frequent engine coolant (antifreeze) additions are
required, or if the level in the recovery bottle does not
drop when the engine cools, the cooling system should
be pressure-tested for leaks.
•Maintain the engine coolant (antifreeze) concentration
at 50% HOAT engine coolant (antifreeze) (minimum)
and distilled water for proper corrosion protection of
your engine which contains aluminum components.
534 MAINTAINING YOUR VEHICLE