Funda o cojín no original que afecta al sensor de ocupación

Something added to the passenger seat that changes what the seat weighs or how weight spreads across it — a fitted cover, a cushion, a beaded mat, an aftermarket heater pad, or objects wedged underneath.

It belongs on this list because it is a genuinely common cause and the only one on it that costs nothing to test. The occupant classification system decides whether to arm the passenger airbag by weighing the seat and reading how that weight is distributed, and it was calibrated against the seat as built. Anything added sits between the occupant and the sensors and shifts both readings.

Distribution matters as much as weight, which is why a light cover can still cause a fault. The system tells a small adult from a strapped-down child seat by the pattern the load makes — a person's weight sits in two concentrated areas, a rigid child seat base spreads it. A taut cover spreads it too.

A tensioned cover is the worst case, because it pulls down on the cushion even with the seat empty, and the system may read an occupant who is not there.

So before anything is dismantled: strip the seat back to bare and see whether the light clears. It is a five-minute check that regularly saves the cost of a module. If a cover is wanted, only one made for that vehicle and marked as compatible with occupant sensing should be used.