Body, generic

B0033 Second Row Left Frontal Stage 3 Deployment Control

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B0033 is the third deployment element of a frontal airbag for the left second-row seat. A third igniter can be a further gas chamber; a Breed patent describes an inflator with one igniter per chamber whose firing order and 0 to 25 ms delays the controller chooses. Mercedes-Benz fills the stage 3 slot of its front bags with the vent valve squib (B000313, B001213), a model for what stage 3 may mean behind a seat. No carmaker documents B0033 for a rear bag. GM bulletin 08-09-41-002H names B0033 with bytes 04, 0D and 0E in its CPA retainer bulletin for numerous GM cars and trucks of 2005 to 2014, where the number belongs to another GM loop. Airbag lamp on.

Likely causes

Connector position assurance lock missing or not seated, so the plug works loose
Damaged stage 3 lead or igniter in the rear airbag
Restraint module configured for equipment the vehicle does not have (wrong part or coding)

Symptoms

  • Airbag warning lamp on
  • Adaptive inflation of the left rear airbag is lost
  • Safety note: do not probe the airbag circuit yourself; unplug airbag connectors only with the battery disconnected and the stated wait time observed

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–1,200
Time1–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

second row left frontal airbagsquib circuitsrs seat wiringsrs control module

Related codes

B0031B0032B003B

References: patents.google.com, static.nhtsa.gov, static.nhtsa.gov, patents.google.com.