2009 JEEP GRAND CHEROKEE sensor

Airbag System Components
The airbag system consists of the following:
•Occupant Restraint Control (ORC)
•Airbag Warning Light
•Driver Airbag
•Passenger Airbag
•Side Curtain Airbags above Side Windows
•Side Remote Acceleration Sensors
•Driver Side Seat Track Position Sensor
•Steering Wheel and Column
•Instrument Panel
•Interconnecting Wiring
•Knee Impact Bolsters
•Front Acceleration Sensors
•Driver and Front Passenger Seat Belt Pretensioners
How the Airbag System Works
•
TheOccupant Restraint Control (ORC)determines if
a frontal, side, or rollover collision is severe enough to
require the front and/or side airbags to inflate. The
front airbag inflators are designed to provide different
rates of airbag inflation from direction provided by the
ORC. The ORC will detect roll overs, not rear impacts.
The ORC also monitors the readiness of the electronic
parts of the system whenever the ignition switch is in
the START or ON positions. These include all of the
items listed above except the knee bolster, the instru-
ment panel, and the steering wheel and column. If the
key is in the LOCK position, in the ACC position, or
not in the ignition, the airbags are not on and will not
inflate.
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 51
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Airbag Warning Light
You will want to have the airbag system ready to inflate
for your protection in an impact. The airbag system is
designed to be maintenance free. If any of the following
occurs, have an authorized dealer service the system
promptly:
•Airbag Warning Light does not come on during the six
to eight seconds after the ignition switch is first turned
on,
•Remains on after the six to eight second interval, or
•Flickers, or comes on and remains on for any period of
time while driving.
NOTE:If the speedometer, tachometer, or any engine
related gauges are not working, the airbag control mod-
ule may also be disabled. The airbags may not be ready
to inflate for your protection. Promptly check the fuseblock for blown fuses. Refer to “Fuses” in Section 7 of this
manual. See your authorized dealer if the fuse is good.
Event Data Recorder (EDR)
In the event of an accident, your vehicle is designed to
record up to five seconds of specific vehicle data param-
eters (see the following list) in an event data recorder
prior to the moment of airbag deployment, or near
deployment, and up to one-quarter second of high-speed
deceleration data during and/or after airbag deployment
or near-deployment. EDR data are ONLY recorded if an
airbag deploys, or nearly deploys, and are otherwise
unavailable.
NOTE:
•A near-deployment event occurs when the airbag
sensor detects severe vehicle deceleration usually in-
dicative of a crash, but not severe enough to warrant
airbag deployment.
56 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

▫To Resume Speed.................... 146
▫To Vary The Speed Setting.............. 146
▫To Accelerate For Passing.............. 147
Rear Park Assist — If Equipped........... 147
▫Rear Park Assist Sensors............... 147
▫Rear Park Assist Warning Display........ 148
▫Enable/Disable The Rear Park Assist...... 150
▫Service The Rear Park Assist............ 150
▫Cleaning The Rear Park Assist........... 151
Rear Camera — If Equipped.............. 151
▫Turning The Rear Camera On Or Off — With
Navigation Radio.................... 152
▫Turning The Rear Camera On Or Off —
Without Navigation Radio.............. 152Overhead Console..................... 153
▫Courtesy/Reading Lights.............. 153
▫Sunglasses Storage................... 154
Garage Door Opener — If Equipped........ 154
▫Programming HomeLink.............. 155
▫Gate Operator/Canadian Programming.... 158
▫Using HomeLink................... 158
▫Reprogramming A Single
HomeLinkButton................... 159
▫Security........................... 159
▫Troubleshooting Tips.................. 159
▫General Information.................. 160
Power Sunroof — If Equipped............ 160
76 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

Rain Sensing Wipers — If Equipped
This feature senses moisture on the windshield and
automatically activates the wipers for the driver. The
feature is especially useful for road splash or overspray
from the windshield washers of the vehicle ahead. Rotate
the end of the multifunction lever to one of five settings
to activate this feature.
The sensitivity of the system can be adjusted with the
multifunction lever. Wiper delay position 1 is the least
sensitive, and wiper delay position 5 is the most sensi-
tive. Setting 3 should be used for normal rain conditions.
Settings 1 and 2 can be used if the driver desires less
wiper sensitivity. Settings 4 and 5 can be used if the
driver desires more sensitivity. Place the wiper switch in
the OFF position when not using the system.
NOTE:
•The rain sensing feature will not operate when the
wiper switch is in the Low or High speed position.
•The rain sensing feature may not function properly
when ice, or dried salt water is present on the wind-
shield.
•Use of Rain-Xor products containing wax or silicone
may reduce rain sensor performance.
•A customer programmable feature in the Electronic
Vehicle Information Center (EVIC) allows the Rain
Sense feature to be turned off. Refer to “Electronic
Vehicle Information Center (EVIC) — Customer-
Programmable Features” in Section 4 of this manual.
The rain sensing system has protection features for the
wiper blades and arms, and will not operate under the
following conditions:
•Low Ambient Temperature— When the ignition is
first turned ON, the rain sensing system will not
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 141
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To Accelerate For Passing
Press the accelerator as you would normally. When the
pedal is released, the vehicle will return to the set speed.
Using Electronic Speed Control On Hills
The transmission may downshift on hills to maintain the
vehicle set speed.
NOTE:The Electronic Speed Control system maintains
speed up and down hills. A slight speed change on
moderate hills is normal.
On steep hills, a greater speed loss or gain may occur so
it may be preferable to drive without Electronic Speed
Control.
REAR PARK ASSIST — IF EQUIPPED
The Rear Park Assist provides visible and audible indi-
cations of the distance between the rear fascia and the
detected obstacle when backing up. Refer to the WarningSection and Note Section for limitations of this system
and recommendations.
The Rear Park Assist will remember the last system state
(enabled or disabled) from the last ignition cycle when
the ignition is changed to the ON position.
The Rear Park Assist can be active only when the shift
lever is in REVERSE. If the Rear Park Assist is enabled at
this shift lever position, the system will be active until the
vehicle speed is increased to approximately 11 mph
(18 km/h) or above. The system will be active again if the
vehicle speed is decreased to speeds less than approxi-
mately 10 mph (16 km/h).
Rear Park Assist Sensors
The four Rear Park Assist Sensors, located in the rear
fascia, monitor the area behind the vehicle that is within
the sensors’ field of view.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 147
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The sensors can detect obstacles from approximately 12
to 59 in (30 to 150 cm) from the rear fascia in the
horizontal direction, depending on the location and
orientation of the obstacle and the type of obstacle.
Rear Park Assist Warning Display
The Rear Park Assist Warning Display, located in the
headliner near the flipper glass, provides both visible and
audible warnings to indicate the distance between the
rear fascia and the detected obstacle.
When the ignition is turned to the ON position, the
warning display will turn ON all of its LEDs for about
one second. Each side of the warning display has six
yellow and two red LEDs. The vehicle is close to the
obstacle when the red LED is ON.
148 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

Cleaning The Rear Park Assist
Clean the Rear Park Assist Sensors with water, car wash
soap and a soft cloth. Do not use rough or hard cloths. Do
not scratch or poke the sensors. Otherwise, you could
damage the sensors.
REAR CAMERA — IF EQUIPPED
Vehicles with a uconnecttunes radio may be equipped
with a rearview camera (located on the rear liftgate) that
allows you to see an on-screen image (on the navigation
radio screen) of the rear of your vehicle, whenever the
vehicle is put into REVERSE.
WARNING!
Drivers must be careful when backing up even when
using the Rear Camera System. Always check care-
fully behind your vehicle, and be sure to check for
pedestrians, animals, other vehicles, obstructions, or
blind spots before backing up. You are responsible
for the safety of your surroundings and must con-
tinue to pay attention while backing up. Failure to do
so can result in serious injury or death.
CAUTION!
•To avoid vehicle damage, the Rear Camera system
should only be used as a parking aid. The Rear
Camera system is unable to view every obstacle or
object in your drive path.
(Continued)
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 151
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tires or wheels on your vehicle, to ensure that the
replacement or alternate tires and wheels allow the TPMS
to continue to function properly.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Do not use tire sealant from a can, or
balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.13. 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 dealership for service.
UNDERSTANDING YOUR INSTRUMENT PANEL 189
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