Toyota Matrix 2009 Owner's Manual page 45

1-7. Safety information
The main SRS airbag system components are shown above. The
SRS airbag system is controlled by the airbag sensor assembly. The
airbag sensor assembly consists of a safing sensor and an airbag
sensor.
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In certain types of severe frontal or side impacts, the SRS airbag sys-
tem triggers the airbag inflators. A chemical reaction in the inflators
quickly fills the airbags with non-toxic gas to help restrain the motion
of the occupants.
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