Ford Explorer 2009 Owner's Manual page 218

Seating and Safety Restraints
The Safety Canopy system is designed to activate when the vehicle
sustains lateral deceleration sufficient to cause the side crash sensor to
close an electrical circuit that initiates Safety Canopy inflation or when
a certain likelihood of a rollover event is detected by the rollover sensor.
The Safety Canopy is mounted to the roof side-rail sheet metal, behind
the headliner, above the first and second row seats. In certain lateral
collisions or rollover events, the Safety Canopy system will be activated,
regardless of which seats are occupied. The Safety Canopy is designed
to inflate between the side window area and occupants to further
enhance protection provided in side impact collisions and rollover events.
The fact that the Safety Canopy system did not activate 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
Safety Canopy is designed to inflate in certain side impact collisions or
rollover events, not in rear impact, frontal or near-frontal collisions,
unless the collision causes sufficient lateral deceleration or rollover
likelihood.
WARNING: Several Safety Canopy system components get hot
after inflation. Do not touch them after inflation.
WARNING: If the Safety
Canopy system has
deployed, the Safety Canopy
will not function again. The
Safety Canopy system
(including the A, B and C
pillar trim) must be inspected
and serviced by an authorized
dealer. If the Safety Canopy is
not replaced, the unrepaired area
will increase the risk of injury in a
collision.
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