What does it mean?
B1323 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Airbag > Weight Classification > WCS Sensor Defect .
Symptoms
- Airbag warning lamp stays on from the moment the ignition is switched on
- Passenger airbag off indicator lit with an adult in the seat, or lit when the seat is empty
- Occupant classification data implausible or frozen at one value
- Passenger seat belt reminder misbehaves
- The restraint system may not respond correctly in a crash, which makes this a genuine safety fault
Likely causes
- Internally failed weight classification sensor whose self-test no longer passes
- Leaking sensor bladder or a load cell that has drifted out of calibration
- Seat cushion foam compressed, damaged or replaced with a non-original part
- Liquid spilled into the seat cushion reaching the sensor
- Sensor damaged during seat cover or heater element replacement
- Loose seat mounting distorting how the sensor is loaded
- Calibration never carried out after previous seat work
How to fix it
- Disconnect the battery and observe the required waiting period before working on restraint components
- Read the weight classification live data with the seat empty and then with a known load applied
- Confirm nothing is stored under the seat and no cargo strap or wire presses on the cushion
- Inspect the sensor and its wiring for spilled liquid, corrosion and crushing
- Verify the seat bolts are torqued correctly and the frame is straight
- Replace the weight classification sensor or cushion assembly with the correct part for the vehicle
- Run the zeroing and calibration routine, then confirm every classification state is reported before releasing the vehicle