B00A0: Occupant Classification System
What to do
The passenger airbag may be switched off, or deploy on the wrong assumption. Remove any seat cover, cushion or heater pad from the passenger seat and see whether the light clears — these systems weigh the seat, and anything added to it can be enough. If the seat has recently been removed or replaced, it likely needs recalibrating.
What this code means
The occupant classification 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.
This is the system-level code, and it sits above the individual sensor codes at B00B0 and B00C0. With a sensor code beside it, this is the consequence. Standing alone, the sensors report healthy and the classification they produce is still not trusted — which points at the module, its calibration, or the mat of sensors as a whole rather than any one element.
One cause is specific to this system and easily missed: anything that changes what the seat weighs. A heavy seat cover, a cushion, an aftermarket heater pad, or objects wedged under the seat all add load the calibration did not expect. So does a seat that has been removed and refitted, because the classification is calibrated to the installed assembly and many vehicles require a recalibration afterwards.
Likely causes
Start here
- Faulty occupant classification module · specialist
- Aftermarket seat cover or cushion affecting the occupant sensor · easy
- Damaged wiring under the front seats · specialist
- Corroded or loose connector · specialist
Less common
- 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
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about B00A0.