Ford Five Hundred (2007 year). Manual — part 33

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 inflate 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).

• side airbags and curtain (if equipped). Refer to Side airbag system

later in this chapter.

• one or more impact and safing sensors.
• Safety belt pretensioner
• a readiness light and tone.
• diagnostic module.
• and the electrical wiring which connects the components.
• Front passenger sensing system. Refer to Front 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.

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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The front passenger sensing system will disable (will not inflate) the
front passenger’s frontal airbag if:
• the front passenger seat is unoccupied, or has small/medium objects in

the front seat,

• the system determines that an infant is present in a rear-facing infant

seat that is installed according to the manufacturer’s instructions,

• the system determines that a small child is present in a forward-facing

child restraint that is installed according to the manufacturer’s
instructions,

• the system determines that a small child is present in a booster seat,
• a front passenger takes his/her weight off of the seat for a period of

time,

• a child or a small person occupies the front passenger seat.
For side airbag equipped vehicles, the front passenger sensing system
will turn off the passenger seat side airbag if:
• the seat is empty and safety belt is unbuckled.
The front passenger sensing system
uses a

⬙passenger airbag off⬙ or

⬙pass airbag off⬙ indicator which will
illuminate and stay lit to remind you
that the front passenger frontal airbag is disabled. The indicator lamp is
located above the glove box on the instrument panel.

Note: The indicator lamp will illuminate for a short period of time when
the ignition is turned to the ON position to confirm it is functional.

When the front passenger seat is not occupied (empty seat) or in the
event that the front passenger frontal airbag is enabled (may inflate), the
indicator lamp will be unlit.

The front passenger sensing system is designed to disable (will not
inflate) the front passenger’s frontal airbag when a rear facing infant
seat, a forward-facing child restraint, or a booster seat is detected.
• When the front passenger sensing system disables (will not inflate)

the front passenger frontal airbag, the indicator lamp will illuminate
and stay lit to remind you that the front passenger frontal airbag is
disabled.

• If the child restraint has been installed and the indicator lamp is not

lit, then turn the vehicle off, remove the child restraint from the
vehicle and reinstall the restraint following the child restraint
manufacturer’s instructions.

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The front passenger sensing system is designed to enable (may inflate)
the front passenger’s frontal airbag anytime the system senses that a
person of adult size is sitting properly in the front passenger seat.
• When the front passenger sensing system enables the front passenger

frontal airbag (may inflate), the indicator will be unlit and stay unlit.

If a person of adult size is sitting in the front passenger’s seat, but the

⬙passenger airbag off⬙ or ⬙pass airbag off⬙ indicator lamp is lit, it is
possible that the person isn’t sitting properly in the seat. If this happens:
• Turn the vehicle off and ask the person to place the seatback in the

full upright position.

• Have the person sit upright in the seat, centered on the seat cushion,

with the person’s legs comfortably extended.

• Restart the vehicle and have the person remain in this position for

about two minutes. This will allow the system to detect that person
and enable the passenger’s frontal airbag.

• If the indicator lamp remains lit even after this, the person should be

advised to ride in the rear seat.

Occupant

Pass Airbag Off
Indicator Light

Passenger Airbag

Empty seat

Unlit

Disabled

Small child in child
safety seat or booster

Lit

Disabled

Small child with safety
belt buckled or
unbuckled

Lit

Disabled

Adult

Unlit

Enabled

Even with Advanced Restraints Systems, children 12 and under
should be properly restrained in the back seat.

After all occupants have adjusted their seats and put on safety belts, it’s
very important that they continue to sit properly. A properly seated
occupant sits upright, leaning against the seat back, and centered on the
seat cushion, with their feet comfortably extended on the floor. Sitting
improperly can increase the chance of injury in a crash event. For
example, if an occupant slouches, lies down, turns sideways, sits forward,
leans forward or sideways, or puts one or both feet up, the chance of
injury during a crash is greatly increased.

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