2008 JEEP WRANGLER coolant temperature

15. Tachometer
This light indicates the engine speed in revolutions per
minute (RPM).
CAUTION!
Do not operate the engine with the tachometer
pointer in the red area. Engine damage will occur.
16. Engine Coolant Temperature Warning Light This light warns of an overheated engine condi-
tion. If the engine is critically hot, a warning chime
will sound 10 times. After the chime turns off, the
engine will still be critically hot until the light goes out.
17. Sentry Key/Security Alarm Indicator Light — If
Equipped
Refer to “Sentry Key Immobilizer System” or “Vehicle
Security Alarm” in Section 2 of this manual. 18. Coolant Temperature Gauge
Indicates engine coolant temperature. The red
zone to the far right indicates possible overheat-
ing. Seek your authorized dealer immediately if
the gauge operates in the red zone. On U.S. vehicles, the
temperature is indicated in degrees fahrenheit; and on
Canadian vehicles in degrees centigrade.
19. Cruise Indicator Light This light shows when the electronic speed
control system is turned on.
20. 4WD Indicator Light — If Equipped This light alerts the driver that the vehicle is in
the four-wheel drive mode, and the front and
rear driveshafts are mechanically locked to-
gether forcing the front and rear wheels to
rotate at the same speed.
UNDERSTANDING YOUR INSTRUMENT PANEL 209
4

ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the cord
to a standard 110-115 Volt AC electrical outlet with a
grounded, three wire extension cord. The engine block
heater cord is found under the hood bundled in front of
the battery tray.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110-115 Volt AC electrical cord could
cause electrocution.
Use the heater when temperatures below 0°F (-18°C) are
expected to last for several days.
MANUAL TRANSMISSION
WARNING!
You or others could be injured if you leave the
vehicle unattended without having the parking
brake fully applied. The parking brake should al-
ways 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 vehicle on a hill with the
clutch pedal partially engaged, as this will cause
abnormal wear on the clutch.
STARTING AND OPERATING 275
5

into the passenger compartment. In addition, inspect the
exhaust system each time the vehicle is raised for lubri-
cation or oil change. Replace as required.
Cooling System
WARNING!
You or others can be badly burned by hot antifreeze/
coolant or steam from your radiator. If you see or hear
steam coming from under the hood, don’t 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 antifreeze/coolant protection every 12 months
(before the onset of freezing weather, where applicable).
If antifreeze/coolant is dirty or rusty in appearance, thesystem should be drained, flushed and refilled with fresh
antifreeze/coolant. 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 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
antifreeze/coolant from the radiator drain cock. If the cap
is sealing properly, the antifreeze/coolant will begin to
drain from the coolant recovery bottle. DO NOT RE-
MOVE THE COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.
394 MAINTAINING YOUR VEHICLE

Adding Engine Coolant
Your vehicle has been built with an improved antifreeze/
coolant that allows extended maintenance intervals. This
antifreeze/coolant can be used up to 5 Years or 100,000
mi (160 000 km) before replacement. To prevent reducing
this extended maintenance period, it is important that
you use the same antifreeze/coolant throughout the life
of your vehicle. Please review these recommendations for
using Hybrid Organic Additive Technology (HOAT)
antifreeze/coolant. When adding antifreeze/coolant:
•The manufacturer recommends using MOPAR
Antifreeze/Coolant 5 Year/100,000 Mile Formula
HOAT (Hybrid Organic Additive Technology).
•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
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 antifreeze/coolant types will decrease
the life of the antifreeze/coolant and will require more
frequent antifreeze/coolant changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
antifreeze/coolant, and to ensure that antifreeze/coolant
will return to the radiator from the coolant reserve tank.
396 MAINTAINING YOUR VEHICLE

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 antifreeze/coolant 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.
Disposal of Used Engine Coolant
Used ethylene glycol based antifreeze/coolant is a regu-
lated substance requiring proper disposal. Check with
your local authorities to determine the disposal rules for
your community. To prevent ingestion by animals orchildren, do not store ethylene glycol based antifreeze/
coolant in open containers or allow it to remain in
puddles on the ground. If ingested by a child, contact a
physician immediately. Clean up any ground spills im-
mediately.
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 antifreeze/coolant 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
antifreeze/coolant freeze point or replacing antifreeze/
coolant. 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.
MAINTAINING YOUR VEHICLE 397
7

Charging System Light.................... 206
Chart, Tire Sizing ........................ 314
Check Engine Light
(Malfunction Indicator Light) .............213,380
Child Restraint .................... 62,63,69,72
Child Restraint Tether Anchors .............68,69
Child Seat .............................. 67
Climate Control ......................... 259
Clock ........................... 224,236,251
Compact Disc (CD) Maintenance ............. 258
Compass .............................. 215
Compass Calibration ..................... 217
Computer, Trip/Travel .................... 215
Console ............................... 118
Console, Floor .......................... 118
Contract, Service ........................ 439
Converter, Catalytic ...................... 386
Cooling System ......................... 394
Adding Coolant (Antifreeze) .............. 396Coolant Capacity
...................... 424
Coolant Level ......................... 397
Disposal of Used Coolant ................ 397
Drain, Flush, and Refill .................. 395
Inspection ........................... 394
Points to Remember .................... 398
Pressure Cap ......................... 396
Selection of Coolant (Antifreeze) .........395,424
Temperature Gauge ..................... 209
Corrosion Protection ..................... 406
Crankcase Emission Control System .......... 388
Cruise Light ........................... 209
Cup Holder ............................ 117
Customer Assistance ..................... 437
Data Recorder, Event ...................... 60
Daytime Running Lights ................... 99
Dealer Service .......................... 382
Defroster, Rear Window ................... 198
448 INDEX

Defroster, Windshield.................. 260,262
Delay (Intermittent) Wipers ................. 100
Diagnostic System, Onboard ................ 379
Digital Video Disc (DVD) Player ............. 250
Dimmer Switch, Headlight .................. 98
Dipsticks Oil (Engine) .......................... 383
Disabled Vehicle Towing ................... 374
Disarming, Theft System ................... 18
Disposal Engine Oil ........................... 385
Used Coolant (Antifreeze) ................ 397
Door Locks ........................... 31,32
Doors ................................. 26
Drive Belts ............................ 386
Driver’s Seat Back Tilt ..................... 87
Driving ............................... 294
Off-Pavement ......................... 294
Off-Road ............................ 294 Dual Top
.............................. 120
Electrical Outlet, Auxiliary (Power Outlet) ...... 116
Electrical Power Outlets ................... 116
Electronic Brake Control System ............. 105
Anti-Lock Brake System ................. 105
Brake Assist System .................... 107
Electronic Roll Mitigation ................ 108
Electronic Stability Program ............... 109
Traction Control System ................. 106
Electronic Roll Mitigation (ERM) ............. 108
Electronic Speed Control (Cruise Control) ...... 102
Electronic Stability Program (ESP) ............ 109
Electronic Throttle Control Warning Light ...... 214
Emergency Brake ........................ 308
Emergency, In Case of Brake Warning Light .................... 207
Coolant Temperature Gauge .............. 209
Hazard Warning Flasher ................. 364
INDEX 449
10

Gasoline/Oxygenate Blends................ 337
Gauges Coolant Temperature .................... 209
Fuel ................................ 206
Odometer ............................ 211
Speedometer ......................... 206
Tachometer .......................... 209
Gear Ranges ........................ 276,281
General Information .................... 17,335
Glass Cleaning .......................... 410
Gross Axle Weight Rating ...............342,345
Gross Vehicle Weight Rating .............342,345
GVWR ............................... 342
Hands-Free Phone (UConnect™) ........85,250,251
Hard Drive (HDD) ....................... 250
HardTop ............................. 125
Hard Top, Modular ...................... 125
Hard Top Removal ....................... 129 Hazard Warning Flasher
................... 364
Head Restraints .......................... 89
Head Rests ............................. 89
Headlights Bulb Replacement ...................... 420
Dimmer Switch ........................ 98
Replacing ............................ 420
Switch ............................... 97
Heater ............................... 259
Heater, Engine Block ..................... 275
High Beam Indicator ..................... 207
Hitches Trailer Towing ........................ 348
Holder, Cup ........................... 117
Hood Release ........................... 94
Hoses ............................. 399,400
Hydraulic Clutch Fluid .................... 403
Ignition ............................... 12
452 INDEX