FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Front Impact Sensor

FRONT IMPACT SENSOR (FIS)




The release system for the front airbag consists of a SRSCM installed in the middle of the vehicle and two front impact sensor (FIS) which are located in front of the vehicle. Only the SRSCM is capable of releasing the airbags or the seat-belt pretensioner system in the vehicle. In the dialog between the SRSCM and the front impact sensor it is the SRSCM which takes the release decision. The SRSCM is supported in connection with the front airbag function by the two front impact sensor, which act as intelligent acceleration sensors and as such back up the central airbag controller. Both the front impact sensors continuously report the current system status of the vehicle to the SRSCM.

When crash occurs, SRSCM decides deployment timing and whether deploy the airbag modules or not according to a Crash Severity Level from the FIS installed around the front bump and a signal from acceleration sensor installed in SRSCM.