2008 FORD EXPLORER sensor

electrical loads as soon as possible. If the warning stays on or comes on
when the engine is operating at normal speeds, have the electrical
system checked as soon as possible.
FUEL LEVEL LOW.Displayed as an early reminder of a low fuel
condition.
PARK BRAKE ENGAGED.Displayed when the manual park brake is
set, the engine is running and the vehicle is driven more than 3 mph (5
km/h). If the warning stays on after the park brake is released, contact
your authorized dealer as soon as possible.
CHECK BRAKE SYSTEM.Displayed when the braking system is not
operating properly. If the warning stays on or continues to come on,
contact your authorized dealer as soon as possible.
CHECK PARK AID (if equipped).Displayed when the transmission is
in R (Reverse) and the Reverse Sensing System (Park Aid) is disabled.
Refer toReverse Sensing System (Park Aid)in this section to enable.
LOW TIRE PRESSURE.Displayed when one or more tires on your
vehicle have low tire pressure. Refer toInflating your tiresin theTires,
Wheels and Loadingchapter.
TIRE MONITOR FAULT.Displayed when the Tire Pressure Monitoring
System is malfunctioning. If the warning stays on or continues to come
on, have the system inspected by your authorized dealer.
TIRE SENSOR FAULT.Displayed when a tire pressure sensor is
malfunctioning, or your spare tire is in use. For more information on how
the system operates under these conditions, refer toUnderstanding
your Tire Pressure Monitoring Systemin theTires, Wheels and
Loadingchapter. If the warning stays on or continues to come on, have
the system inspected by your authorized dealer.
BRAKE FLUID LEVEL LOW.Indicates the brake fluid level is low and
the brake system should be inspected immediately. Refer toBrake fluid
reservoirin theMaintenance and Specificationschapter.
CHECK HEADLAMP.Displayed when the headlamps are activated and
at least one bulb is burned out. Check the lamps as soon as possible and
have the burned out lamp replaced. Refer toReplacing headlamp bulbs
in theLightschapter.
CHECK HIGHBEAM LAMP.Displayed when the highbeam lamps are
activated and at least one bulb is burned out. Check the lamps as soon
as possible and have the burned out lamp replaced. Refer toReplacing
headlamp bulbsin theLightschapter.
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Before returning the seatback to its original position, make sure
that cargo or any objects are not trapped behind the seatback.
After returning the seatback to its original position, pull on the
seatback to ensure that it has fully latched. An unlatched seat may
become dangerous in the event of a sudden stop or collision.
SAFETY RESTRAINTS
Personal Safety System™
The Personal Safety System™ provides an improved overall level of
frontal crash protection to front seat occupants and is designed to help
further reduce the risk of airbag-related injuries. The system is able to
analyze different occupant conditions and crash severity before activating
the appropriate safety devices to help better protect a range of
occupants in a variety of frontal crash situations.
Your vehicle’s Personal Safety System™ consists of:
•Driver and passenger dual-stage airbag supplemental restraints.
•Front safety belts with pretensioners, energy management retractors,
and safety belt usage sensors.
•Driver’s seat position sensor.
•Front passenger sensing system
•“Passenger airbag off” or “pass airbag off” indicator lamp
•Front crash severity sensor.
•Restraints Control Module (RCM).
•Restraint system warning light and back-up tone.
•The electrical wiring for the airbags, crash sensor(s), safety belt
pretensioners, front safety belt usage sensors, driver seat position
sensor, front passenger sensing system, and indicator lights.
How does the Personal Safety System™ work?
The Personal Safety System™ can adapt the deployment strategy of your
vehicle’s safety devices according to crash severity and occupant
conditions. A collection of crash and occupant sensors provides
information to the Restraints Control Module (RCM). During a crash, the
RCM may activate the safety belt pretensioners and/or either one or both
stages of the dual-stage airbag supplemental restraints based on crash
severity and occupant conditions.
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The fact that the pretensioners or airbags did not activate for both front
seat occupants in a collision does not mean that something is wrong with
the system. Rather, it means the Personal Safety System™ determined
the accident conditions (crash severity, belt usage, etc.) were not
appropriate to activate these safety devices. Front airbags are designed
to activate only in frontal and near-frontal collisions, not rollovers,
side-impacts, or rear-impacts unless the collision causes sufficient
longitudinal deceleration.
Driver and passenger dual-stage airbag supplemental restraints
The dual-stage airbags offer the capability to tailor the level of airbag
inflation energy. A lower, less forceful energy level is provided for more
common, moderate-severity impacts. A higher energy level is used for
the most severe impacts. Refer toAirbag supplemental restraints
section in this chapter.
Front crash severity sensor
The front crash severity sensor enhances the ability to detect the
severity of an impact. Positioned up front, it provides valuable
information early in the crash event on the severity of the impact. This
allows your Personal Safety System™ to distinguish between different
levels of crash severity and modify the deployment strategy of the
dual-stage airbags and safety belt pretensioners.
Driver’s seat position sensor
The driver’s seat position sensor allows your Personal Safety System™ to
tailor the deployment level of the driver dual-stage airbag based on seat
position. The system is designed to help protect smaller drivers sitting
close to the driver airbag by providing a lower airbag output level.
Front passenger sensing system
For airbags to do their job they must inflate with great force, and this
force can pose a potentially deadly risk to occupants that are very close
to the airbag when it begins to inflate. For some occupants, this occurs
because they are initially sitting very close to the airbag. For other
occupants, this occurs when the occupant is not properly restrained by
safety belts or child safety seats and they move forward during pre-crash
braking. The most effective way to reduce the risk of unnecessary
injuries is to make sure all occupants are properly restrained. Accident
statistics suggest that children are much safer when properly restrained
in the rear seating positions than in the front.
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Air bags can kill or injure a child in a child seat.NEVERplace a
rear-facing child seat in front of an active air bag. If you must
use a forward-facing child seat in the front seat, move the seat all the
way back.
Always transport children 12 years old and under in the back
seat and always properly use appropriate child restraints.
The front passenger sensing system can automatically turn off the front
passenger airbag and passenger seat-mounted side airbag. The system is
designed to help protect small (child size) occupants from frontal airbag
deployments when they are seated or restrained in the front passenger
seat contrary to proper child-seating or restraint usage
recommendations. Even with this technology, parents areSTRONGLY
encouraged to always properly restrain children in the rear seat. The
sensor also turns off the passenger front airbag and passenger
seat-mounted side airbag when the passenger seat is empty.
Front safety belt usage sensors
The front safety belt usage sensors detect whether or not the driver and
front outboard passenger safety belts are fastened. This information
allows your Personal Safety System™ to tailor the airbag deployment
and safety belt pretensioner activation depending upon safety belt usage.
Refer toSafety restraintssection in this chapter.
Front safety belt pretensioners
The safety belt pretensioners at the front outboard seating positions are
designed to tighten the safety belts firmly against the occupant’s body
during frontal collisions, and in side collisions and rollovers. This helps
increase the effectiveness of the safety belts. In frontal collisions, the
safety belt pretensioners can be activated alone or, if the collision is of
sufficient severity, together with the front airbags.
Front safety belt energy management retractors
The front outboard safety belt energy management retractors allow webbing
to be pulled out of the retractor in a gradual and controlled manner in
response to the occupant’s forward momentum. This helps reduce the risk
of force-related injuries to the occupant’s chest by limiting the load on the
occupant. Refer toSafety restraintssection in this chapter.
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Determining if the Personal Safety System™ is operational
The Personal Safety System™ uses a warning light in the instrument cluster
or a back-up tone to indicate the condition of the system. Refer to the
Warning lights and chimessection in theInstrument Clusterchapter.
Routine maintenance of the Personal Safety System™ is not required.
The Restraints Control Module (RCM) monitors its own internal circuits
and the circuits for the airbag supplemental restraints, crash sensor(s),
safety belt pretensioners, front safety belt buckle sensors, front
passenger sensing system, and the driver seat position sensor. In
addition, the RCM also monitors the restraints warning light in the
instrument cluster. A difficulty with the system is indicated by one or
more of the following:
•The warning light will either flash or stay lit.
•The warning light will not illuminate immediately after the ignition is
turned on.
•A series of five beeps will be heard. The tone pattern will repeat
periodically until the problem and warning light are repaired.
If any of these things happen, even intermittently, have the Personal Safety
System™ serviced at an authorized dealer immediately. Unless serviced,
the system may not function properly in the event of a collision.
Safety restraints precautions
Always drive and ride with your seatback upright and the lap
belt snug and low across the hips.
To reduce the risk of injury, make sure children sit in the back
seat where they can be properly restrained.
Never let a passenger hold a child on his or her lap while the
vehicle is moving. The passenger cannot protect the child from
injury in a collision.
All occupants of the vehicle, including the driver, should always
properly wear their safety belts, even when an airbag
supplemental restraint system (SRS) is provided.
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Do not attempt to service, repair, or modify the airbag
supplemental restraint systems or its fuses. See your authorized
dealer.
Modifications to the front end of the vehicle, including frame,
bumper, front end body structure and non-Ford tow hooks may
effect the performance of the airbag sensors increasing the risk of
injury. Do not modify the front end of the vehicle with anything other
than authorized Ford accessories for your vehicle.
Additional equipment may affect the performance of the airbag
sensors increasing the risk of injury. Please refer to theBody
Builders Layout Bookfor instructions about the appropriate
installation of additional equipment.
Children and airbags
Children must always be properly
restrained. Accident statistics
suggest that children are safer when
properly restrained in the rear
seating positions than in the front
seating position. Failure to follow
these instructions may increase the
risk of injury in a collision.
Airbags can kill or injure a
child in a child seat.
NEVERplace a rear-facing child
seat in front of an active airbag. If
you must use a forward-facing
child seat in the front seat, move
the seat all the way back.
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How does the airbag supplemental restraint system work?
The airbag SRS is designed to
activate when the vehicle sustains
longitudinal deceleration sufficient
to cause the sensors to close an
electrical circuit that initiates airbag
inflation.
The fact that the airbags did not
inflate in a collision does not mean
that something is wrong with the
system. Rather, it means the forces
were not of the type sufficient to
cause activation. Front airbags are designed to activate in frontal and
near-frontal collisions, not rollover, side-impact, or rear-impacts unless
the collision causes sufficient longitudinal deceleration.
The airbags inflate and deflate
rapidly upon activation. After airbag
deployment, it is normal to notice a
smoke-like, powdery residue or
smell the burnt propellant. This may
consist of cornstarch, talcum
powder (to lubricate the bag) or
sodium compounds (e.g., baking
soda) that result from the
combustion process that inflates the
airbag. Small amounts of sodium
hydroxide may be present which
may irritate the skin and eyes, but
none of the residue is toxic.
While the system is designed to help
reduce serious injuries, contact with
a deploying airbag may also cause abrasions, swelling or temporary
hearing loss. Because airbags must inflate rapidly and with considerable
force, there is the risk of death or serious injuries such as fractures,
facial and eye injuries or internal injuries, particularly to occupants who
are not properly restrained or are otherwise out of position at the time
of airbag deployment. Thus, it is extremely important that occupants be
properly restrained as far away from the airbag module as possible while
maintaining vehicle control.
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Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the air bag has deployed,the air bag will not function
again and must be replaced immediately.If the air bag is not
replaced, the unrepaired area will increase the risk of injury in a
collision.
The SRS consists of:
•driver and passenger airbag modules (which include the inflators and
airbags).
•seat-mounted side airbags. Refer toSeat-mounted side airbag system
later in this chapter
•Safety Canopy™ system. Refer toSafety Canopy™ systemlater in
this chapter.
•one or more impact and safing sensors.
•a readiness light and tone.
•diagnostic module.
•and the electrical wiring which connects the components.
•Front passenger sensing system. Refer toFront passenger sensing
system.later in this chapter.
•“Passenger airbag off” or “pass airbag off” indicator lamp. Refer to
Front passenger sensing systemlater in this chapter.
The diagnostic module monitors its own internal circuits and the
supplemental airbag electrical system wiring (including the impact
sensors), the system wiring, the airbag system readiness light, the airbag
back up power and the airbag ignitors.
Front passenger sensing system
The front passenger sensing system is designed to meet the regulatory
requirements of Federal Motor Vehicle Safety Standard (FMVSS) 208
and is designed to disable (will not inflate) the front passenger’s frontal
airbag under certain conditions.
The front passenger sensing system works with sensors that are part of
the front passenger’s seat and safety belt. The sensors are designed to
detect the presence of a properly seated occupant and determine if the
front passenger’s frontal airbag should be enabled (may inflate) or
disabled (will not inflate).
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