2012 JEEP WRANGLER service

Window Fogging
Interior fogging on the windshield can be quickly re-
moved by turning the mode selector to Defrost. The
Defrost/Floor mode can be used to maintain a clear
windshield and provide sufficient heating. If side win-
dow fogging becomes a problem, increase blower speed.
Vehicle windows tend to fog on the inside in mild but
rainy or humid weather.
NOTE:Recirculate without A/C should not be used for
long periods as fogging may occur.
Side Window Demisters
A side window demister outlet is located at each end of
the instrument panel. These non-adjustable outlets direct
air toward the side windows when the system is in the
Floor, Mix, or Defrost mode. The air is directed at the area
of the windows through which you view the outside
mirrors.
Outside Air Intake
Make sure the air intake, located directly in front of the
windshield, is free of obstructions such as leaves. Leaves
collected in the air intake may reduce airflow, and if they
enter the plenum, they could plug the water drains. In
winter months, make sure the air intake is clear of ice,
slush, and snow.
A/C Air Filter — If Equipped
The A/C Filter prevents most dust and pollen from
entering the cabin. The filter acts on air coming from
outside the vehicle and recirculated air within the pas-
senger compartment. Refer to “Maintenance Procedures”
in “Maintaining Your Vehicle” for A/C Air Filter service
information or see your authorized dealer for service.
Refer to “Maintenance Schedules” for filter service
intervals.
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UNDERSTANDING YOUR INSTRUMENT PANEL 365

When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) feature (refer to “Electronic Range Select
(ERS)” in this section) to select a lower gear range. Under
these conditions, using a lower gear range will improve
performance and extend transmission life by reducing
excessive shifting and heat buildup.
Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in the current gear until the vehicle is brought to a stop.
After the vehicle has stopped, the transmission will
remain in second gear regardless of which forward gear
is selected. PARK, REVERSE, and NEUTRAL will con-
tinue to operate. The Malfunction Indicator Light (MIL)may be illuminated. Limp Home Mode allows the vehicle
to be driven to an authorized dealer for service without
damaging the transmission.
In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the engine OFF.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no
longer detected, the transmission will return to normal
operation.
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NOTE:Even if the transmission can be reset, we recom-
mend that you visit your authorized dealer at your
earliest possible convenience. Your authorized dealer has
diagnostic equipment to determine if the problem could
recur.
If the transmission cannot be reset, authorized dealer
service is required.
Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control allows the
driver to limit the highest available gear when the shift
lever is in the DRIVE position. For example, if you shift
the transmission into 3 (third gear), the transmission will
never shift above third gear, but will shift down into
second and first gear normally.
You can switch between DRIVE and ERS mode at any
vehicle speed. When the shift lever is in the DRIVE
position, the transmission will operate automatically,
shifting between all available gears. Tapping the shift lever to the left (-) will downshift the transmission,
activate ERS mode, display the current gear in the
instrument cluster, and maintain that gear as the top
available gear. Once in ERS mode, tapping the shift lever
to the left (-) or right (+) will change the top available
gear.
To exit ERS mode, simply press and hold the shift lever to
the right (+) until “D” is once again displayed in the shift
lever position indicator in the instrument cluster.
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid, causing an accident
or personal injury.
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STARTING AND OPERATING 389

the slowest current can push the heaviest vehicle down-
stream and out of control if the water is deep enough to
push on the large surface area of the vehicle’s body.
Before you proceed, determine the speed of the current,
the water’s depth, approach angle, bottom condition and
if there are any obstacles. Then cross at an angle heading
slightly upstream using the low and slow technique.
WARNING!
Never drive through fast moving deep water. It can
push your vehicle downstream, sweeping it out of
control. This could put you and your passengers at
risk of injury or drowning.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Inspect the radiator for mud and debris and clean as
required.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
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STARTING AND OPERATING 411

NOTE:
•Increased noise levels at the end of the steering wheel
travel are considered normal and do not indicate that
there is a problem with the power steering system.
•Upon initial start-up in cold weather, the power steer-
ing pump may make noise for a short amount of time.
This is due to the cold, thick fluid in the steering
system. This noise should be considered normal, and it
does not in any way damage the steering system.
WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
CAUTION!
Prolonged operation of the steering system at the end
of the steering wheel travel will increase the steering
fluid temperature and it should be avoided when
possible. Damage to the power steering pump may
occur.
Power Steering Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through an autho-
rized dealer.5
STARTING AND OPERATING 413

CAUTION!
If the “Brake Warning Light” remains on with the
parking brake released, a brake system malfunction
is indicated. Have the brake system serviced by an
authorized dealer immediately.
ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type, and tires must be properly inflated to produce
accurate signals for the computer.
WARNING!
Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low speed self-
test at about 12 mph (20 km/h). If for any reason your
foot is on the brake when the vehicle reaches 12 mph
(20 km/h), this check will be delayed until 25 mph
(40 km/h).
The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation; this is normal.
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STARTING AND OPERATING 417

Enabling HDC
1. Shift the transfer case into 4WD LOW range. Refer to
“Four-Wheel Drive Operation” in “Starting and Operat-
ing” for further information.
2. Press the “Hill Descent” button. The “Hill Descent
Control Indicator Light” in the instrument cluster will
turn on solid.
NOTE:If the transfer case is not in 4WD LOW range,
the “Hill Descent Control Indicator Light” will flash for
five seconds and HDC will not be enabled.
Disabling HDC
1. Press the “Hill Descent” button or shift the transfer
case out of 4WD LOW range. The “Hill Descent Control
Indicator” light in the instrument cluster will turn off.TIRE SAFETY INFORMATION
Tire Markings
1 — U.S. DOT Safety
Standards Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and Temperature Grades
432 STARTING AND OPERATING

EXAMPLE:
Service Description: 95= Load Index
— A numerical code associated with the maximum load a tire can carry
H = Speed Symbol
— A symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions
— The maximum speed corresponding to the speed symbol should only be achieved under
specified operating conditions (i.e., tire pressure, vehicle loading, road conditions, and
posted speed limits)
Load Identification: ....blank.... = Absence of any text on the sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL) = Extra load (or reinforced) tire
Light Load (LL) = Light load tire
C, D, E, F, G = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load — Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure — Maximum pressure indicates the maximum permissible cold tire inflation pressure for
this tire
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