Body, generic

B0049 Third Row Right Frontal Stage 1 Deployment Control

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B0049 marks the stage 1 charge of a right third-row frontal bag, the main charge of a bag that would have to come out of the second-row seatback ahead of it. Daimler's application for a bag mounted behind a front seat and Mercedes-Benz's later design with chambers that bridge a changing seat gap show how such a bag can be built; in series, Mercedes offers rear frontal airbags only for the outer second-row seats of its S-Class and Maybach models. No carmaker documents B0049 and no bulletin cites it. A third-row frontal code on a vehicle without that equipment points to a module set up for the wrong variant. Airbag lamp on.

Likely causes

Loose connector of the airbag lead in the second-row seatback
Lead strained when the second-row seat is folded or slid
Restraint module configured for equipment the vehicle does not have (wrong part or coding)

Symptoms

  • Airbag warning lamp on
  • Frontal airbag for the right third-row seat may not deploy
  • 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

third row right frontal airbagsquib circuitsrs seat wiringsrs control module

Related codes

B004AB004BB0041B0048

References: patents.google.com, patents.google.com, media.mbusa.com.