2006 JEEP GRAND CHEROKEE sensor

Airbag System Components
The airbag system consists of the following:
•Occupant Restraint Control Module
•Airbag Warning Light
•Driver Airbag
•Passenger Airbag
•Side Curtain Airbags above Side Windows (If
Equipped)
•Side Remote Acceleration Sensors (If Equipped)
•Steering Wheel and Column
•Instrument Panel
•Interconnecting Wiring
•Knee Impact Bolsters
•Front Acceleration Sensors
•Driver and Front Passenger Seat Belt Pretensioner
•Occupant Classification System (OCS) — Front Pas-
senger Seat Only (If Equipped)
Occupant Classification Module
Passenger Airbag Disable (PAD) Indicator Light
Weight Sensors
How The Airbag System Works
•
TheOccupant Restraint Control (ORC) Modulede-
termines 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 direc-
tion provided by the ORC. The ORC may also modify
the rate of inflation based on the occupant size pro-
vided by the Occupant Classification Module. The
ORC will detect roll overs, not rear impacts.
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 47
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The OCS classifies an occupant using weight sensors
mounted in the base of the front passenger seat. Any
weight on the seat will be sensed by the system. Objects
hanging on the seat or other passengers pushing down
on the seat will also be sensed. The weight of an adult
will cause the system to turn the airbag on. In this case,
the OCS has classified the occupant of the seat as an
adult. An adult occupant needs to sit in a normal position
(with their feet on or near the floor) in order to be
properly classified. Reclining the seat back too far may
change how an occupant is classified by the OCS.
Drivers and adult passengers should verify that the
“PAD Indicator Light” is not illuminated when an adult
is riding in the front passenger seat. If an adult occu-
pant’s weight is transferred to another part of the vehicle
(like the door or instrument panel), the weight sensors in
the seat may not properly classify the occupant. Objects
lodged under the seat or between the seat and the center
console can prevent the occupant’s weight from beingmeasured properly and may result in the occupant being
improperly classified. Ensure that the front passenger
seat back does not touch anything placed on the back seat
because this can also affect occupant classification. Also,
if you fold down the rear seat check to be sure it doesn’t
touch the front passenger seat.
If the front passenger seat is damaged in any way, it
should only be serviced by an authorized dealer. If the
seat is removed (or even if the seat attachment bolts are
loosened or tightened in any way), take the vehicle to an
authorized dealer.
If there is a fault present in the OCS, the “Airbag Warning
Light” (a red light located in the center of the instrument
cluster directly in front of the driver) will be turned on.
This indicates that you should take the vehicle to an
authorized dealer. The “Airbag Warning Light” is turned
on whenever there is fault that can affect the operation of
the airbag system. If there is a fault present in the OCS,
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 51
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both the “PAD Indicator Light” and the “Airbag Warning
Light” are illuminated to show that the passenger airbag
is turned off until the fault is cleared. If an object is
lodged under the seat and interferes with operation of
the weight sensors, a fault will occur which turns on both
the “PAD Indicator Light” and the “Airbag Warning
Light.” Once the lodged object is removed, the fault will
be automatically cleared after a short period of time.
•TheDriver and Passenger Airbag/Inflator Unitsare
located in the center of the steering wheel and the right
side of the instrument panel. When the ORC detects a
collision requiring the airbags, it signals the inflator
units. A large quantity of nontoxic gas is generated to
inflate the front airbags. Different airbag inflation rates
are possible, based on collision severity and occupant
size. The steering wheel hub trim cover and the upper
right side of the instrument panel separate and fold
out of the way as the bags inflate to their full size. The
bags fully inflate in about 50–70 milliseconds. This isabout half of the time it takes to blink your eyes. The
bags then quickly deflate while helping to restrain the
driver and front passenger.
The driver front airbag gas is vented through the vent
holes in the sides of the airbag. The passenger front
airbag gas is vented through the vent holes in the sides
of the airbag. In this way, the airbags do not interfere
with your control of the vehicle.•TheOccupant Classification Module (OCM)is lo-
cated beneath the front passenger seat. The OCM
classifies the occupant into categories based on the
measurements made by the seat weight sensors. The
OCM communicates with the Occupant Restraint Con-
trol (ORC) Module. The ORC uses the occupant cat-
egory to determine whether the front passenger airbag
should be turned off. It also determines the rate of
airbag inflation during a collision.
52 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

•Your vehicle has fourWeight Sensorslocated between
the seat and the floor pan. The weight sensors measure
applied weight and transfers that information to the
OCM.
•TheSide Impact SRS Side Curtain Airbagsare de-
signed to activate only in certain side or rollover
collisions. When the ORC (with side impact option)
detects a collision requiring the side curtain airbag to
inflate, it signals the inflators on the crash side of the
vehicle. A quantity of nontoxic gas is generated to
inflate the side curtain airbag. The inflating side cur-
tain airbag pushes the outside edge of the headliner
out of the way and covers the window. The airbag
inflates in about 30 milliseconds (about one quarter of
the time it takes to blink your eyes) with enough force
to injure you if you are not belted and seated properly,
or if items are positioned in the area where the sidecurtain airbag inflates. This especially applies to chil-
dren. The side curtain airbag is only about 3
12inches
(9 cm) thick when it is inflated.
•TheKnee Impact Bolstershelp protect the knees of
the driver and the front passenger, and position every-
one for the best interaction with the front airbag.
The front passenger seat assembly contains critical com-
ponents that affect the front passenger airbag deploy-
ment. Correctly functioning front passenger seat compo-
nents are critical for the Occupant Classification System
(OCS) to properly classify the front passenger and calcu-
late the proper airbag deployment. Do not make any
modifications to the front passenger seat components,
assembly, or to the seat cover.
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 53
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▫Turn Signals.........................124
▫High Beam Switch....................125
▫Passing Light........................125
▫Headlight Time Delay..................125

Windshield Wipers And Washers............126
▫Mist...............................127
▫Speed Sensitive Intermittent Wiper System . . . 127
▫Rain Sensing Wipers—If Equipped.........128

Tilt Steering Column....................130

Electronic Brake Control System............130
▫ABS (Anti-Lock Brake System)............131
▫TCS (Traction Control System)............132
▫BAS (Brake Assist System)...............132▫ERM (Electronic Rollover Mitigation).......133
▫ESP (Electronic Stability Program).........134
▫ESP/BAS Warning Lamp And
ESP/TCS Indicator Light................137

Rear Park Assist System— If Equipped.......138
▫Rear Park Assist Sensors................138
▫Rear Park Assist Warning Display.........139
▫Enable/Disable The Rear Park Assist System . . 140
▫Service The Rear Park Assist System........141
▫Cleaning The Rear Park Assist System......141

Adjustable Pedals — If Equipped...........144

Electronic Speed Control..................146
▫To Activate..........................146
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 75
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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)” 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
operate until the wiper switch is moved, vehicle speed
is greater than 0 mph (0 km/h), or the outside tem-
perature is greater than 32°F (0°C).
•Transmission in N (Neutral) Position— When the
ignition is ON, and the transmission is in the N
(Neutral) position, the rain sensing system will not
operate until the wiper switch is moved, vehicle speed
is greater than 5 mph (8 km/h), or the shift lever is
moved out of the N (Neutral) position.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 129
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WARNING!
Many factors, such as vehicle loading, road condi-
tions and driving conditions, influence the chance
that wheel lift or rollover may occur. ERM cannot
prevent all wheel lift or roll overs, especially those
that involve leaving the roadway or striking objects
or other vehicles. Only a safe, attentive, and skillful
driver can prevent accidents. The capabilities of an
ERM-equipped vehicle must never be exploited in a
reckless or dangerous manner which could jeopar-
dize the user’s safety or the safety of others.
ESP (Electronic Stability Program)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESP cor-
rects for over/under steering of the vehicle by applying
the brake of the appropriate wheel to assist in counter-
acting the over/under steer condition. Engine power
may also be reduced to help the vehicle maintain the
desired path.
ESP uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESP applies the brake of the appropri-
ate wheel to assist in counteracting the oversteer or
understeer condition.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
134 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

REAR PARK ASSIST SYSTEM— IF EQUIPPED
The Rear Park Assist System provides visual and audible
indications of the distance between the rear fascia and the
detected obstacle when backing up. Refer to the Warning
Section and Note Section for limitations of this system
and recommendations.
The Rear Park Assist System will remember the last
system state (enabled or disabled) from the last ignition
cycle when the ignition is changed to the RUN/ON
position.
The Rear Park Assist System can be active only when the
shifter is in R (Reverse). If the Rear Park Assist System is
enabled at this shifter 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
approximately 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. The monitored area seems oval
in shape.
The sensors can detect obstacles from approximately 11.8
inches (30 cm) up to 59 inches (150 cm) from the rear
fascia in the horizontal direction, depending on the
location and orientation of the obstacle and the type of
obstacle.
138 UNDERSTANDING THE FEATURES OF YOUR VEHICLE