B0057 code meaning
Third Row Center Seat Belt Sensor
What B0057 means
In J2012, B0057 is the buckle sensor for the third row's centre seat, a position found only in eight-seat vans and SUVs. FMVSS 208 S7.5(c) will require a belt warning there from September 2028. No carmaker documents B0057 publicly with this meaning. Older GM airbag modules give the number a different job: the 2006 Saab 9-5 and the Saab 9-3 store B0057 when the passenger pretensioner loop resistance stays under 1.5 ± 0.2 ohms for 2 seconds. GM bulletin 14609 lists B0057 with B0058, B0059 and B0064 to B0066 on 2004-09 Colorado and Canyon extended cabs, whose rear door harness can suffer fatigue breaks and can disable the front pretensioners; GM extended coverage to 10 years. On older GM vehicles, check the pretensioner loop first.
B0057 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of B0057
- Airbag warning lamp on
- Depending on the module: wrong belt status for the middle third-row seat, or passenger pretensioner possibly inactive
- Safety note: buckle and pretensioner plugs carry firing circuits nearby; only unplug them with the battery disconnected and the wait time observed
Common causes of B0057
- PossibleFaulty buckle sensor or lead at the middle third-row seat
- PossibleOlder GM trucks: broken wire in the rear door harness to the pretensioner (bulletin 14609)
- Less likelyOlder GM/Saab module: shorted passenger pretensioner squib or connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Seat belt buckle switchSRS seat wiringPassenger seatbelt pretensionerSRS control module
What each part of B0057 means
| B | Body system: airbags, seat belts, power seats, lights and climate control. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 57 | The exact fault in that area. |
What to do next
- Note B0057 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about B0057
What does B0057 mean?
B0057 means "Third Row Center Seat Belt Sensor". In J2012, B0057 is the buckle sensor for the third row's centre seat, a position found only in eight-seat vans and SUVs. It is a generic code, so it means the same on every make.
Is it safe to drive with B0057?
B0057 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will B0057 fail an emissions test?
B0057 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is B0057 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will B0057 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.