B0030 code meaning
Second Row Left Side Airbag Deployment Control
What B0030 means
In J2012 the B003x block covers the second seat row, and B0030 is the left rear side airbag, mounted in the rear door or the outer backrest. Mitsubishi files B0030 under the rear side airbag module LH and sets a short to another circuit after 2 seconds. Mercedes-Benz reads B003013 as an open squib in the left rear sidebag on the A-Class, CLA and GLB, often caused by higher contact resistance at the restraint unit connector (LI54.21-P-070658). The older GM numbering differs: on the 2006 Saab 9-5, B0030 is a passenger side airbag loop whose pin voltage is above 4.1 or below 1.0 volts for 2 seconds, and the Saab 9-3 reads it as a passenger side bag short. The right-hand rear twin is B0038. Airbag lamp on.
B0030 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 B0030
- Airbag warning lamp on
- Rear left side airbag may not deploy in a side impact
- Safety note: do not probe the airbag circuit yourself; unplug airbag connectors only with the battery disconnected and the stated wait time observed
Common causes of B0030
- Most likelyRaised contact resistance at the restraint module or rear side airbag connector
- PossibleDamaged lead in the rear door transition or rear seat backrest
- Less likelyInternal fault in the rear left side airbag module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Second row left side airbagSRS control moduleSRS wiring
What each part of B0030 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). |
| 30 | The exact fault in that area. |
What to do next
- Note B0030 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 B0030
What does B0030 mean?
B0030 means "Second Row Left Side Airbag Deployment Control". In J2012 the B003x block covers the second seat row, and B0030 is the left rear side airbag, mounted in the rear door or the outer backrest. It is a generic code, so it means the same on every make.
Is it safe to drive with B0030?
B0030 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will B0030 fail an emissions test?
B0030 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 B0030 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will B0030 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.