B0079Driver Seat Belt Pretensioner B Deployment Control
- Generic OBD-II code · Body
- How the car detects it
- B0079 marks the driver's second (B) pretensioner. Mercedes-Benz uses the code in exactly this way: in LI54.21-P-070658, valid for A-Class, CLA and GLB, B007913 is an open circuit in the squib of the belt end fitting tensioner on the driver's side, while the retractor of the same seat appears as B007E. An end fitting or anchor pretensioner pulls on the lower belt anchor next to the door side of the seat and so tightens the lap section; GM's restraint guide and a Hyundai-Kia patent describe this layout. Older Saab models give the number another meaning: the 2006 Saab 9-5 stores B0079 when an incorrect driver-side side-impact sensor is installed. A stored B0079 lights the airbag lamp and means the driver's lap tensioner may not fire.
- What you may notice
- Airbag warning lamp on
- Driver's lap belt section not tightened in a crash
- Safety note: the end fitting tensioner is pyrotechnic; never probe it live – battery off, wait time, specialist workshop
- Likely causes
- LikelyPlug at the driver's belt end fitting tensioner beside the seat loose or corroded
- PossibleLead to the end fitting tensioner pinched by the seat rail
- RareOn a 2006 Saab 9-5, wrong side-impact sensor fitted (older GM meaning)
- RareInternal fault of the end fitting tensioner squib
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.