B00A1: Occupant Position System
What to do
The car will drive normally and the airbag warning light will be on. The airbag can still deploy, but without the adjustment for how you are sitting — worth having fixed rather than lived with, and worth sitting upright and properly belted in the meantime.
What this code means
The occupant position system has reported a fault.
Occupant sensing exists because a deploying airbag is dangerous to somebody in the wrong place, and the system has to know who is in the seat before it decides what to do.
The problem it solves is real and was learned expensively. Early airbags deployed at one force regardless of who was there, and they injured and killed children and small adults in crashes that would otherwise have been survivable. A bag inflating at three hundred kilometres an hour into someone sitting close to it is a weapon, which is why the industry moved to systems that can soften, delay or suppress deployment.
Two quite different questions are being asked, and the standard gives them separate codes. Classification asks who — an adult, a small adult, a child, a child seat, or an empty seat — and is answered mostly by weight. Position asks where — how far the occupant is from the airbag, and whether they are leaning into its path.
Both matter because either alone gives wrong answers. A heavy adult leaning forward is in as much danger from the bag as a light one sitting normally, and weight cannot see that.
Position sensing answers the question weight cannot: is this person too close to the airbag, or leaning into where it will go?
"Out of position" is the term of art, and it covers ordinary human behaviour — leaning forward to adjust the radio, a child kneeling up to look out, someone slumped asleep against the door. A bag that is right for a person sitting upright and belted can injure the same person leaning forward, because it meets them while it is still inflating rather than after it has filled.
How it is measured varies more than any other part of this system: ultrasonic sensors in the headliner, infrared, capacitive sensing in the seat back, or a camera. Which one a vehicle uses determines what the sensor letters mean, and only its own documentation says.
Losing it does not usually disable the airbag — it removes the refinement, so the module falls back to a fixed deployment that assumes a normally seated occupant. Safe for most people in most crashes, and exactly the assumption the system exists to avoid making.
Likely causes
Start here
- Faulty occupant classification module · specialist
- Damaged wiring under the front seats · specialist
- Corroded or loose connector · specialist
Less common
- Damaged wiring harness · specialist
- Faulty restraints control module · specialist
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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