2008 FORD FOCUS sensor

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).
•side airbags. Refer toSide airbag systemlater in this chapter.
•side air curtain system. Refer toSide air curtain systemlater in this
chapter.
•safety belt pretensioners
•one or more impact and safing sensors.
•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 system.later in this chapter.
•a readiness light and tone.
•diagnostic module.
•and the electrical wiring which connects the components.
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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Do not attempt to service, repair, or modify the airbag SRS, its
fuses or the seat cover on a seat containing an airbag. See your
authorized dealer.
All occupants of the vehicle should always wear their safety belts
even when an airbag SRS is provided.
How does the side airbag system work?
The design and development of the
side airbag system included
recommended testing procedures
that were developed by a group of
automotive safety experts known as
the Side Airbag Technical Working
Group. These recommended testing
procedures help reduce the risk of
injuries related to the deployment of
side airbags.
The side airbag system consists of
the following:
•An inflatable nylon bag (airbag)
with a gas generator concealed
behind the outboard bolster of
the driver and front passenger
seatbacks.
•A special seat cover designed to allow airbag deployment.
•The same warning light, electronic control and diagnostic unit as used
for the front airbags.
•Two pressure sensors located in the front doors.
•Two crash sensors located between the “A” and “B” pillars.
Side airbags, in combination with safety belts, can help reduce the risk of
severe injuries in the event of a significant side impact collision.
The side airbags are fitted on the outboard side of the seatbacks of the
front seats. In certain lateral collisions, the airbag on the side affected by
the collision will be inflated. The front passenger sensing system will
turn off the passenger seat side airbag if the seat is empty (unless for
some reason the safety belt is properly buckled). If the front passenger
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seat is empty, and the safety belt is not properly buckled, the front
passenger seat side airbag will be turned off by the front passenger
sensing system. The airbag was designed to inflate between the door
panel and occupant to further enhance the protection provided
occupants in side impact collisions.
The airbag SRS is designed to activate when the vehicle sustains lateral
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. Side airbags are designed
to inflate in side-impact collisions, not roll-over, rear-impact, frontal or
near-frontal collisions, unless the collision causes sufficient lateral
deceleration.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the side airbag has
deployed,the airbag will
not function again. The side
airbag system (including the
seat) must be inspected and
serviced by an authorized
dealer.If the airbag is not
replaced, the unrepaired area will
increase the risk of injury in a
collision.
Side curtain airbag system
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How does the side air curtain system work?
The design and development of the
side air curtain system included
recommended testing procedures
that were developed by a group of
automotive safety experts known as
the Side Airbag Technical Working
Group. These recommended testing
procedures help reduce the risk of
injuries related to the deployment of
side airbags (including side air
curtain systems).
The side air curtain system consists
of the following:
•An inflatable nylon curtain with a
gas generator concealed behind
the headliner and above the
doors.
•The headliner will flex to open
above the side doors to allow air curtain deployment.
•The same warning light, electronic control and diagnostic unit as used
for the front airbags.
•Two crash sensors located under the outboard side of the front seats,
attached near the floor.
•Two crash sensors located at the base of the “C” pillars above the
wheel house.
Side air curtains and side airbags, in combination with safety belts, can
help reduce the risk of severe injuries in the event of a significant side
impact collision.
Children 12 years old and under should always be properly restrained in
the rear seats. The side air curtain will not interfere with children
restrained using a properly installed child or booster seat because it is
designed to inflate downward from the headliner above the doors along
the side window openings.
The side air curtains are mounted to the sheet metal above the first and
second row seats. In certain lateral collisions, the air curtain and
seat-mounted side airbag on the side affected by the collision will be
inflated, except that the passenger sensing system will deactivate the
passenger seat-mounted side airbag if it detects an empty unbuckled
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passenger seat. The air curtain was designed to inflate between the side
window area and occupant to further enhance the head protection
provided to occupants in side impact collisions. The seat-mounted side
airbag was designed to inflate between the door panel and occupant to
further enhance the protection provided occupants in side impact
collisions.
The side air curtain system SRS is designed to activate when the vehicle
sustains lateral deceleration sufficient to cause the sensors to close an
electrical circuit that initiates air curtain and seat-mounted side airbag
inflation.
The fact that the side air curtain and seat-mounted side airbag 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. The side air curtain system is designed to inflate in side
impact collisions, not roll-over, rear impact, frontal or near-frontal
collisions, unless the collision causes sufficient lateral deceleration.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the side air curtain has
deployed,the air curtain
will not function again. The
side air curtain system
(including the A, B and C
pillar trim and headliner) must
be inspected and serviced by
an authorized dealer.If the air
curtain is not replaced, the
unrepaired area will increase the
risk of injury in a collision.
Determining if the system is operational
The SRS uses a readiness light in the instrument cluster or a tone to
indicate the condition of the system. Refer to theAirbag readiness
section in theInstrument Clusterchapter. Routine maintenance of the
side airbag is not required.
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When mounting replacement tires and wheels, you should not
exceed the maximum pressure indicated on the sidewall of the
tire to set the beads without additional precautions listed below. If the
beads do not seat at the maximum pressure indicated, re-lubricate and
try again.
When inflating the tire for mounting pressures up to 20 psi greater
than the maximum pressure on the tire sidewall, the following
precautions must be taken to protect the person mounting the tire:
1. Make sure that you have the correct tire and wheel size.
2. Lubricate the tire bead and wheel bead seat area again.
3. Stand at a minimum of 12 ft. (3.66 m) away from the tire wheel
assembly.
4. Use both eye and ear protection.
For a mounting pressure more than 20 psi greater than the maximum
pressure, a Ford Dealer or other tire service professional should do the
mounting.
Always inflate steel carcass tires with a remote air fill with the person
inflating standing at a minimum of 12 ft. (3.66 m) away from the tire
wheel assembly.
Important:Remember to replace the wheel valve stems when the road
tires are replaced on your vehicle.
It is recommended that the two front tires or two rear tires generally be
replaced as a pair.
The tire pressure sensors mounted in the wheels (if equipped) are not
designed to be used in aftermarket wheels.
The use of wheels or tires not recommended by Ford Motor Company
may affect the operation of your Tire Pressure Monitoring System (if
equipped).
If the TPMS indicator is flashing, your TPMS is malfunctioning. Your
replacement tire might be incompatible with your TPMS, or some
component of the TPMS may be damaged (if equipped).
Safety practices
Driving habits have a great deal to do with your tire mileage and safety.
•Observe posted speed limits
•Avoid fast starts, stops and turns
•Avoid potholes and objects on the road
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Changing tires with TPMS
Each road tire is equipped with
a tire pressure sensor fastened
to the inside rim of the wheel.
The pressure sensor is covered
by the tire and is not visible
unless the tire is removed. The
pressure sensor is located
opposite (180 degrees) from the
valve stem. Care must be taken
when changing the tire to avoid
damaging the sensor.It is
recommended that you always have
your tires serviced by an authorized
dealer.
The tire pressure should be checked
periodically (at least monthly) using
an accurate tire gauge, refer to
Inflating your tiresin this chapter.
Understanding your Tire Pressure Monitoring System (TPMS)
The Tire Pressure Monitoring System measures pressure in your four
road tires and sends the tire pressure readings to your vehicle. The Low
Tire Pressure Warning Lamp will turn ON if the tire pressure is
significantly low. Once the light is illuminated, your tires are under
inflated and need to be inflated to the manufacturer’s recommended tire
pressure. Even if the light turns ON and a short time later turns OFF,
your tire pressure still needs to be checked. Visit www.checkmytires.org
for additional information.
When your temporary spare tire is installed
When one of your road tires needs to be replaced with the temporary
spare, the TPMS system will continue to identify an issue to remind you
that the damaged road wheel/tire needs to be repaired and put back on
your vehicle.
To restore the full functionality of the Tire Pressure Monitoring System,
have the damaged road wheel/tire repaired and remounted on your
vehicle. For additional information, refer toChanging tires with TPMS
in this section.
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CHANGING A FLAT TIRE
If you get a flat tire while driving:
•do not brake heavily.
•gradually decrease the vehicle’s speed.
•hold the steering wheel firmly.
•slowly move to a safe place on the side of the road.
Your vehicle may be equipped with a conventional spare tire that is
different in one or more of the following: type, brand, size, speed rating
and tread design. If this is the case, this dissimilar spare tire is still rated
for your vehicle loads (GAWR and GVWR). This temporary spare tire is
not equipped with a Tire Pressure Monitor System (TPMS) sensor.
Note:The tire pressure monitoring system (TPMS) indicator light will
illuminate when the spare is in use. To restore the full functionality of
the TPMS system, all road wheels equipped with the tire pressure
monitoring sensors must be mounted on the vehicle.
Have a flat tire serviced by an authorized dealer in order to prevent
damage to the TPMS sensor, refer toTire Pressure Monitoring System
(TPMS)in theTires, Wheels, and Loadingchapter. Replace the spare
tire with a road tire as soon as possible. During repairing or replacing of
the flat tire, have the authorized dealer inspect the TPMS sensor for
damage.
The use of tire sealants may damage your Tire Pressure
Monitoring System and should only be used if it is supplied with
your vehicle as part of the original temporary mobility kit.
Refer toTire Pressure Monitoring System (TPMS)in theTire,
Wheels and Loadingchapter for important information. If the
tire pressure monitor sensor becomes damaged, it will no longer
function.
Dissimilar spare tire/wheel information
Failure to follow these guidelines could result in an increased
risk of loss of vehicle control, injury or death.
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