Body, generic

B007E Driver Seat Belt Pretensioner C Deployment Control

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B007E is the driver's third (C) pretensioner circuit. Mercedes-Benz fills this slot with the retractor: in LI54.21-P-070658 for the A-, CLA- and GLB-Class, B007E13 is an open circuit at the squib of the driver's emergency tensioning retractor, with B0079 for the belt end fitting tensioner and B0080 for the driver's belt force limiter. The retractor unit is housed either inside the B-pillar or within the seat and winds the spool back to remove slack from the shoulder belt, as GM and Joyson explain. The same Mercedes list puts the rear retractors on the C codes B00E3, B00E4, B00E6 and B00E7, so there the C stage consistently means the retractor. A stored B007E means the airbag lamp is on and the driver's shoulder belt will not be pretensioned.

Likely causes

Retractor plug at the lower driver-side B-pillar loose or terminals spread
Harness pinched by B-pillar or sill trim
Internal fault of the driver retractor pretensioner

Symptoms

  • Airbag warning lamp on
  • Driver's shoulder belt is not tightened in a crash
  • Safety note: the retractor holds a pyrotechnic charge; disconnect the battery, wait, and leave the work to a specialist workshop

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–700
Time0.5–2.5 h

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

Parts involved

driver pretensioner csquib circuitsrs control module

Related codes

B0070B0079B007FB0080

References: static.nhtsa.gov, static.nhtsa.gov, joysonsafety.com, gmstc.com.