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Seat Occupancy Detection (OC3)



Seat Occupancy Detection (OC3)

The seat occupancy detection consists of a seat occupancy mat on which pressure-sensitive sensors are fitted. In addition, the seat occupancy mat has a hard-wire connection to an electronic evaluation unit. The weight classification is based on evaluating the impression created by the person when taking their seat. The seat occupancy detection cannot measure weights. Due to the activation of individual cells of the seat occupancy mat, a weight class is determined by the electronic evaluation unit. The electronic evaluation unit sends cyclical information on the classification to the airbag control unit.

Seat occupancy detection
Data exchange between the seat occupancy detection and the airbag control unit is across a hardware cable. The seat occupancy detection monitors the inputs and outputs. Possible fault states are stored in the fault code memory of the airbag control unit.
If there is a defect in the seat occupancy detection, the seat occupancy mat including foam part must be replaced. After replacement of the seat occupancy mat, the fault code memory of the airbag control unit contains the following entry: "Seat occupancy detection, passenger: not released". After replacement of the seat occupancy mat, the seat mat must be released.



NOTE: All work on the airbag must only be conducted with the battery disconnected.Connect and disconnect airbag control unit, sensors and gas generators only with the battery disconnected.The airbag control unit contains vehicle-specific data and must therefore be encoded before placing into operation.Removal and installation in other vehicles is prohibited.