B00A1
Occupant Position System.
- Generic
- Body
- Generic code
- Medium severity
How this code is built
- B
- SystemBody
- 0
- Defined bySAE, the same on every car
- 0
- AreaBody area 0
- A1
- FaultThe specific fault in that area
What it means
B00A1 is the generic code for a fault in the Occupant Position System. This is the part of the restraint system that tells the airbag control unit where an occupant is sitting or how they are positioned, so it can decide how to deploy the airbags. The control unit has seen a missing, implausible or out-of-range signal or circuit fault from the occupant position sensing, and it has logged the code and usually lit the airbag warning light. The exact sensors involved (seat position, occupant classification, or others) vary by manufacturer and model.
Symptoms
- Airbag or SRS warning light on the dashboard
- Passenger airbag off or on indicator showing incorrectly or flickering
- Front airbag status not matching whether the seat is occupied
- Fault appears after someone sits on or moves the seat, or after seat or trim work
- Intermittent warning light that comes and goes with seat movement
Possible causes
- Damaged, pinched or corroded wiring or connector under the affected seat, often from seat movement or items stored underneathlikely
- Faulty occupant position or seat sensor, or a sensor out of its calibrated statelikely
- Poor connection at the seat or airbag control unit connector after seat removal, trim work or a previous repairpossible
- Low or unstable supply voltage to the restraint system from a weak battery or poor earthpossible
- Liquid spills or contamination affecting the seat sensing components or connectorspossible
- Internal fault in the airbag control unit or occupant classification modulerare
How to diagnose
- Read all stored codes and freeze frame or status data, and note whether B00A1 is current, intermittent or stored from history, plus any other restraint codes
- Check the airbag warning light behaviour at key on and whether the occupant status indicator matches the seat occupancy
- Visually inspect the seat wiring, connectors and any sensor mats for damage, routing problems, corrosion or spill marks
- Check the battery condition and charging voltage, and inspect the relevant earth points
- With the battery disconnected and the correct waiting time observed, reseat the seat and control unit connectors and check pins for damage or looseness
- Reconnect, clear the code and see whether it returns when the seat is moved, loaded or wiggled while watching live data
- Check the sensor signal and circuit resistance against the manufacturer's data for that model, without probing airbag circuits with a test lamp
- Check for software updates or technical bulletins that apply to that model before replacing the control unit
How to fix
- Repair or replace damaged wiring and connectors, and secure the routing away from moving seat parts
- Replace the faulty occupant position or seat sensor, and carry out any required setup or calibration procedure for the model
- Clean and refit loose or contaminated connectors, or replace them if corroded
- Restore good battery condition and repair any earth or supply fault
- Replace the airbag or occupant classification control unit only if testing proves it faulty, and code or initialise it as the manufacturer requires
Can I keep driving?
The car can usually still be driven, but the airbags may not respond correctly in a crash, so have it checked soon. Avoid carrying a child or small passenger in the affected seat until the fault is fixed.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.