B0043 code meaning
Third Row Left Frontal Stage 3 Deployment Control
What B0043 means
B0043 completes the left third-row frontal group as its stage 3 element. By analogy with front airbags this can be a vent valve squib, as Mercedes-Benz uses for B000313 and B001213, or a further gas chamber like the third chamber in Breed's patent that is kept for a second collision. No public source ties B0043 to a third-row bag. GM gives the number a separate, documented meaning in its older modules: the Saab 9-5 of 2006 stores B0043 if the driver stage 2 terminal sits above 4.1 V or under 1.0 V for 2 seconds, and the 9-3 splits it into shorts to supply, to ground or to another firing loop. Check which airbag the scan tool names. Airbag lamp on.
B0043 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of B0043
- Airbag warning lamp on
- Third deployment element of this airbag is disabled
- 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 B0043
- PossibleDamaged stage 3 lead or squib
- Less likelyShort between two firing loops in a shared harness
- Less likelyRestraint module configured for equipment the vehicle does not have (wrong part or coding)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Third row left frontal airbagSquib circuitSRS seat wiringSRS control module
What each part of B0043 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). |
| 43 | The exact fault in that area. |
What to do next
- Note B0043 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 B0043
What does B0043 mean?
B0043 means "Third Row Left Frontal Stage 3 Deployment Control". B0043 completes the left third-row frontal group as its stage 3 element. It is a generic code, so it means the same on every make.
Is it safe to drive with B0043?
B0043 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will B0043 fail an emissions test?
B0043 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 B0043 to fix?
Difficulty: workshop only. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will B0043 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.