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Occupant Classification Module

Works out who is sitting in the passenger seat — empty, a child or child restraint, a small occupant, or an adult — from a sensing mat, a fluid-filled bladder or strain gauges in the seat frame. The passenger airbag is then enabled, disabled or deployed at reduced force accordingly, which is what the passenger airbag off lamp reports.

Its faults are overwhelmingly physical rather than electrical, and mostly innocent. Anything loading the seat from above or below corrupts the reading: a bag or a jack wedged under the frame, a heavy aftermarket seat cover, a cushion, a floor mat trapped under the rails, or a child seat belted in tightly.

And the system must be re-zeroed after almost any work on that seat — a step skipped constantly when a seat comes out for carpet drying or wiring. Emptying the seat and the space beneath it, removing any cover and sitting in it normally is a free first test that resolves a good proportion of these.

Also known as: ocs, ocs module, occupant classification, seat weight sensor, passenger seat sensor, occupant sensor, seat occupancy sensor, weight sensing system

Referenced by 33 codes

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Codes involving this component (33)

Other components in Body, Interior and Safety

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