B0154Passenger Buckle Switch Circuit Malfunction
- Generic OBD-II code · Body
- How the car detects it
- B0154 has no entry in the publicly available J2012 lists, and carmakers do not describe it in public material; J2012 assigns the front passenger buckle sensor to B0052, which this title duplicates. On the passenger side the buckle signal does more than drive a reminder: together with seat occupancy it helps the restraint module choose how the passenger airbag and pretensioner act. TRW's US5966784A reads latch state from the direction of a magnetic field through a Hall device; US5898366A guides the flux through a spring-loaded armature that touches the latch. For passenger cars built from 1 September 2028, FMVSS 208 applies its new belt warning rules (S7.5) to the front outboard seats as well. Typical result: wrong or missing passenger reminder, often with the airbag lamp.
- What you may notice
- Passenger belt reminder wrong, permanently on or missing
- Airbag warning lamp on
- Safety note: seat plugs share space with airbag and pretensioner wiring; disconnect the battery and wait before unplugging anything
- Likely causes
- LikelyBuckle connector under the passenger seat loose, corroded or kicked off
- PossibleBuckle wire chafed by the seat rail or a seat adjustment
- PossibleSwitch inside the buckle worn or soiled by spilled drinks
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €60 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.