B0003Driver Frontal Stage 3 Deployment Control
- Generic OBD-II code · Body
- How the car detects it
- Some driver airbag modules carry a third pyrotechnic element in addition to the two inflator stages, and B0003 covers its firing loop. FCA lists the code as driver frontal squib 3; its STAR case S2108000180 found B0003-2B (wires shorted together) next to B0001 and B0002 when connector locks behind the steering wheel were not engaged. Mercedes-Benz uses B000313 for the squib of the vent valve inside the driver airbag, which lets gas escape so the cushion becomes softer. An FCA patent describes such an active vent that the airbag electronics opens or keeps closed using data from occupant classification. With this loop faulted, the bag loses its third stage or adaptive venting, while the two inflator stages may still work. The airbag lamp lights up.
- What you may notice
- Airbag warning lamp on, often together with B0001 or B0002
- Adaptive venting or third deployment stage unavailable
- Safety note: do not probe the airbag circuit yourself; unplug airbag connectors only with the battery disconnected and the stated wait time observed
- Likely causes
- LikelyConnector position assurance lock at the airbag module not engaged
- PossibleThird squib or vent valve squib in the airbag module faulty
- RareDamaged clock spring conductor for the third circuit
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €80 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.