How does the Personal Safety System work?

How does the Personal Safety System work?  - Personal safety system™ - Seating and Safety Restraints - Lincoln MKZ Owners Manual - Lincoln MKZ

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.

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. The pretensioners are designed to activate in frontal and near-frontal collisions, and in side collisions when the seat-mounted side airbags and side curtains activate.

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