coolant temperature JEEP WRANGLER UNLIMITED 2013 Owners Manual

13. Air Bag Warning Light
This light will turn on for four to eight seconds
as a bulb check when the ignition switch is first
turned to ON/RUN. If the light is either not on
during starting, stays on, or turns on while
driving, have the system inspected at an authorized
dealer as soon as possible. Refer to “Occupant Restraints”
in “Things To Know Before Starting Your Vehicle” for
further information.
14. Rear Axle Lock Indicator — If Equipped
This light indicates when the rear axle lock has
been activated.
15. Tachometer
Indicates the engine speed in revolutions per minute
(RPM x 1000). CAUTION!Do not operate the engine with the tachometer
pointer in the red area. Engine damage will occur.
16. Coolant Temperature Warning Light
This light warns of an overheated engine condition.
If the light turns on while driving, safely pull over
and stop the vehicle. If the A/C system is on, turn it off.
Also, shift the transmission into NEUTRAL and idle the
vehicle. If the temperature reading does not return to
normal, turn the engine off immediately and call for
service.
NOTE: As the coolant temperature gauge approaches
 H,  this indicator will illuminate and a single chime will
sound. Further overheating will cause the temperature304 UNDERSTANDING YOUR INSTRUMENT PANEL

gauge to pass  H.  In this case, a continuous chime will
sound, until the engine is allowed to cool or the 4 minutes
duration is expired, whichever come first.
17. Vehicle Security Light — If Equipped
This light will flash at a fast rate for approxi-
mately 15 seconds, when the vehicle security
alarm is arming, and then will flash slowly
until the vehicle is disarmed.
18. Temperature Gauge
The temperature gauge shows engine coolant tempera-
ture. Any reading within the normal range indicates that
the engine cooling system is operating satisfactorily.
The gauge pointer will likely indicate a higher tempera-
ture when driving in hot weather, up mountain grades,
or when towing a trailer. It should not be allowed to
exceed the upper limits of the normal operating range. CAUTION!Driving with a hot engine cooling system could
damage your vehicle. If the temperature gauge reads
“H” pull over and stop the vehicle. Idle the vehicle
with the air conditioner turned off until the pointer
drops back into the normal range. If the pointer
remains on the “H” and you hear continuous chimes,
turn the engine off immediately and call an autho-
rized dealer for service.
WARNING!A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. You may want to call an authorized dealer
for service if your vehicle overheats. If you decide to (Continued)
4 UNDERSTANDING YOUR INSTRUMENT PANEL 305

CAUTION!Driving with a hot cooling system could damage your
vehicle. If the temperature gauge reads HOT (H), pull
over and stop the vehicle. Idle the vehicle with the air
conditioner turned off until the pointer drops back
into the normal range. If the pointer remains on HOT
(H), and you hear continuous chimes, turn the engine
off immediately, and call for service.
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.
6 WHAT TO DO IN EMERGENCIES 539

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 (antifreeze). 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 verti-
cally 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
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.
7 MAINTAINING YOUR VEHICLE 577

CAUTION! (Continued)• Do not use water alone or alcohol-based engine
coolant (antifreeze) products. Do not use additional
rust inhibitors or antirust products, as they may not
be compatible with the radiator engine coolant and
may plug the radiator.
• This vehicle has not been designed for use with
propylene glycol-based engine coolant (antifreeze).
Use of propylene glycol-based engine coolant (an-
tifreeze) is not recommended.
Adding 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 ten years or 150,000 miles (240,000 km) before replace-
ment. To prevent reducing this extended maintenance period, it is important that you use the same engine
coolant (antifreeze) throughout the life of your vehicle.
Please review these recommendations for using Organic
Additive Technology (OAT) engine coolant (antifreeze).
When adding engine coolant (antifreeze):
• The manufacturer recommends using MOPAR 
Antifreeze/Coolant 10 Year/150,000 Mile Formula
OAT (Organic Additive Technology) or equivalent.
• Mix a minimum solution of 50% OAT 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.
7 MAINTAINING YOUR VEHICLE 579

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 is not
recommended and can result in cooling system damage.
Drain, flush, and refill as soon as possible to avoid
damage if coolant types are mixed in an emergency.
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
recovery 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
engine 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.
• Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or en-
gine damage may result.580 MAINTAINING YOUR VEHICLE

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 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. 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.
7 MAINTAINING YOUR VEHICLE 581

ABS (Anti-Lock Brake System) ............... .303
Adding Engine Coolant (Antifreeze) ........... .579
Adding Fuel ............................ .510
Additives, Fuel .......................... .509
Airbag ..................................62
Airbag Deployment ........................71
Airbag Light .............................74
Airbag Maintenance ........................73
Airbag, Side ..............................70
Air Cleaner, Engine (Engine Air Cleaner Filter) . . . .569
Air Conditioner Maintenance ................ .571
Air Conditioning ......................... .392
Air Conditioning Controls .................. .392
Air Conditioning Filter .................... .402
Air Conditioning, Operating Tips ............. .403
Air Conditioning Refrigerant ................ .571
Air Conditioning System ................... .392
Air Pressure, Tires ........................ .483
Alarm Light ............................ .305 Alarm (Security Alarm) ......................19
Alterations/Modifications, Vehicle ...............9
Antenna, Satellite Radio .................... .352
Antifreeze (Engine Coolant) ................. .578
Disposal ............................ .581
Anti-Lock Brake System (ABS) ............... .455
Anti-Lock Warning Light ................... .303
Appearance Care ........................ .591
Arming Theft System (Security Alarm) ...........20
Assistance Towing ........................ .130
Auto Down Power Windows ..................42
Automatic Door Locks ......................39
Automatic Headlights ..................... .168
Automatic Oil Change Indicator .............. .325
Automatic Temperature Control (ATC) ......... .396
Automatic Transmission ................... .420
Adding Fluid ........................ .588
Fluid and Filter Changes ................ .588
Fluid Change ........................ .588634 INDEX

Requirements ........................ .506
Tank Capacity ........................ .610
Fueling ............................... .510
Fuses ................................. .598
Gas Cap (Fuel Filler Cap) .................. .510
Gasoline, Clean Air ....................... .507
Gasoline (Fuel) .......................... .506
Gasoline, Reformulated .................... .507
Gauges
Coolant Temperature ................... .305
Fuel ............................... .300
Odometer ........................... .308
Speedometer ......................... .300
Tachometer .......................... .304
Gear Ranges ............................ .415
Gear Select Lever Override ................. .554
General Information ........................19
Glass Cleaning .......................... .594 Gross Axle Weight Rating .................. .516
Gross Vehicle Weight Rating ................. .515
GVWR ................................ .513
Hands-Free Phone (Uconnect™) ...............114
HardTop.............................. .202
Hard Top, Modular ....................... .202
Hard Top Removal ....................... .210
Hazard Warning Flasher ................... .538
Headlights
Automatic ........................... .168
Bulb Replacement ..................... .607
High Beam .......................... .170
High Beam/Low Beam Select Switch ........ .170
Passing ............................. .170
Replacing ........................... .607
Switch ............................. .167
Head Restraints ......................... .160
Heated Mirrors ...........................113640 INDEX

Shoulder Belt Upper Anchorage ................55
Side Airbag ..............................70
Side Window Demisters (Defrosters) ........... .402
Signals, Turn ........................... .103
Snow Chains (Tire Chains) .................. .492
Snow Tires ............................. .486
Soft Top ............................... .221
Spare Tire .............................. .487
Speed Control (Cruise Control) ............... .178
Speedometer ............................ .300
Starting .................................28
Automatic Transmission ................. .410
Cold Weather .........................411
Engine Block Heater .................... .413
Engine Fails to Start .....................411
Manual Transmission ................... .410
Remote ...............................28
Steering
Power .............................. .450 Tilt Column .......................... .177
Wheel, Tilt .......................... .177
Steering Wheel Audio Controls .............. .389
Steering Wheel Mounted Sound System Controls . . .389
Storage ............................... .605
Storage, Behind the Seat ................... .190
Storage, Vehicle .......................... .401
Storing Your Vehicle ...................... .605
Stuck, Freeing ........................... .552
Sunrider ............................... .280
Supplemental Restraint System - Airbag ..........62
Sway Bar Disconnect, Electronic .............. .434
Swing Gate, Rear ..........................44
Synthetic Engine Oil ...................... .568
System, Remote Starting .....................28
Tachometer ............................. .304
Temperature Control, Automatic (ATC) ......... .396
Temperature Gauge, Engine Coolant ........... .305648 INDEX