2009 JEEP COMMANDER fuel cap

5. Malfunction Indicator Light (MIL)
The Malfunction Indicator Light (MIL) is part of
an onboard diagnostic system called OBD II that
monitors engine and automatic transmission con-
trol systems. The light will illuminate when the key is in
the ON position before engine start. If the bulb does not
come on when turning the key from OFF to ON, have the
condition checked promptly.
Certain conditions such as a loose or missing gas cap,
poor fuel quality, etc. may illuminate the light after
engine start. The vehicle should be serviced if the light
stays on through several of your typical driving cycles. In
most situations the vehicle will drive normally and will
not require towing.
The Malfunction Indicator Light flashes to alert you to
serious conditions that could lead to immediate loss of
power or severe catalytic converter damage. The vehicle
should be serviced as soon as possible if this occurs.6. Airbag Warning Light
This light turns on and remains on for six to
eight seconds as a bulb check when the ignition
switch is first turned ON. If the light is not on
during starting, stays on, or turns on while
driving, have the system inspected by an authorized
dealer as soon as possible.
7. Anti-Lock Brake (ABS) Light
This light monitors the Anti-Lock Brake System
(ABS). The light will turn on when the ignition
switch is turned to the ON position and may
stay on for as long as four seconds.
If the ABS light remains on or turns on while driving, it
indicates that the Anti-Lock portion of the brake system
is not functioning and that service is required. However,
the conventional brake system will continue to operate
normally if the BRAKE warning light is not on.
UNDERSTANDING YOUR INSTRUMENT PANEL 193
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▫General Information................... 366
Fuel Requirements..................... 367
▫3.7/4.7L Engine (If Equipped)............ 367
▫5.7L Engine (If Equipped)............... 367
▫Reformulated Gasoline................. 368
▫Gasoline/Oxygenate Blends............. 368
▫E-85 Usage In Non-Flex Fuel Vehicles...... 369
▫MMT In Gasoline.................... 369
▫Materials Added To Fuel............... 370
▫Fuel System Cautions.................. 370
▫Carbon Monoxide Warnings............. 371
Flexible Fuel (4.7L Engine Only) —
If Equipped........................... 372▫E-85 General Information............... 372
▫Ethanol Fuel (E-85)................... 373
▫Fuel Requirements.................... 373
▫Selection Of Engine Oil For Flexible Fuel
Vehicles (E-85) And Gasoline Vehicles...... 374
▫Starting........................... 374
▫Cruising Range...................... 374
▫Replacement Parts.................... 375
Adding Fuel......................... 375
▫Fuel Filler Cap (Gas Cap)............... 375
Vehicle Loading....................... 378
▫Certification Label.................... 378
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Economy
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Underinflation also increases tire
rolling resistance and results in higher fuel consumption.
Ride Comfort and Vehicle Stability
Proper tire inflation contributes to a comfortable ride.
Overinflation produces a jarring and uncomfortable ride.
Both underinflation and overinflation affect the stability
of the vehicle and can produce a feeling of sluggish
response or over responsiveness in the steering.
Unequal tire pressures can cause erratic and unpredict-
able steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver’s side “B” Pillar.
The pressure should be checked and adjusted, as well as
inspected for signs of tire wear or visible damage, at least
once a month. Use a good quality pocket-type gauge to
check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are underinflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage it.
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CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement
equipment that is not of the same size, type, and/or
style. Aftermarket wheels can cause sensor dam-
age. Do not use aftermarket tire sealants or balance
beads if your vehicle is equipped with a TPMS, as
damage to the sensors may result.
•After inspecting or adjusting the tire pressure
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the valve
stem, which could damage the Tire Pressure Moni-
toring Sensor.NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, or to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
•The TPMS is not a substitute for proper tire maintenance,
and it is the driver ’s responsibility to maintain correct tire
pressure using an accurate tire gauge, even if under-
inflation has not reached the level to trigger illumination
of the Tire Pressure Monitoring Telltale Light.
•Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
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FLEXIBLE FUEL (4.7L ENGINE ONLY) — IF
EQUIPPED
E-85 General Information
The information in this section is for Flexible Fuel ve-
hicles only. These vehicles can be identified by a unique,
yellow fuel filler cap (gas cap) that statesEthanol (E-85)/
Unleaded Gasoline,and by theFLEXFUELbadge that
will be located on the body of your vehicle. This section
only covers those subjects that are unique to these
vehicles. Please refer to the other sections of this manual
for information on features that are common between
Flexible Fuel and gasoline-only powered vehicles.
E-85 Fuel Cap
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CAUTION!
Only vehicles with the E-85 fuel filler cap (gas cap)
can operate on E-85.
ETHANOL FUEL (E-85)
E-85 is a mixture of approximately 85% fuel ethanol and
15% unleaded gasoline.
WARNING!
Ethanol vapors are extremely flammable and could
cause serious personal injury. Never have any smok-
ing materials lit in or near the vehicle when remov-
ing the fuel filler tube cap (gas cap) or filling the
tank. Do not use E-85 as a cleaning agent and never
use it near an open flame.
Fuel Requirements
If your vehicle is E-85 compatible, it will operate on
unleaded gasoline with an octane rating of 87, or E-85
fuel, or any mixture of these two fuels.
E-85 Badge
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consumption. You can expect your MPG and your driv-
ing range to decrease by about 30% compared to gasoline
operation.
Replacement Parts
All components in your Flexible Fuel Vehicle (FFV) are
designed to be compatible with ethanol. Always be sure
that your vehicle is serviced with correct ethanol com-
patible parts.
CAUTION!
•Replacing fuel system components with non-
ethanol compatible components can damage your
vehicle.
•Do not use ethanol mixture greater than 85% in
your vehicle. It will cause difficulty in cold start-
ing and may affect drivability.
ADDING FUEL
Fuel Filler Cap (Gas Cap)
The gas cap is located behind the fuel filler door, on the
driver’s side of the vehicle. If the gas cap is lost or
damaged, be sure the replacement cap is for use with this
vehicle.
Fuel Filler Cap
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CAUTION!
•Damage to the fuel system or emission control
system could result from using an improper fuel
cap (gas cap). A poorly fitting cap could let impu-
rities into the fuel system. Also, a poorly fitting
aftermarket cap can cause the Malfunction Indica-
tor Light to illuminate, due to fuel vapors escaping
from the system.
•A poorly fitting gas cap may cause the Malfunc-
tion Indicator Light to turn on.
•To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.
NOTE:When the fuel nozzle “clicks” or shuts off, the
fuel tank is full.
WARNING!
•Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank filled.
•Never add fuel when the engine is running. This is
in violation of most state and federal fire regula-
tions and will cause the malfunction indicator
light to turn on.
NOTE:Tighten the gas cap about one–quarter turn until
you hear one click. This is an indication that cap is
properly tightened.
If the gas cap is not tighten properly, the Malfunction
Indicator Light will come on. Be sure the gas cap is
tightened every time the vehicle is refueled.
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