Left-hand (driver's side in LHD vehicles) seat belt pretensioner.
: Corrosion or loose pins in the yellow SRS connectors, often caused by vibration or moisture. nissan b1432-1a
Place a known radar-transparent material (cardboard or thin plastic) over the bumper area. If the code clears momentarily, the issue is external. If not, move inside. Left-hand (driver's side in LHD vehicles) seat belt