B00E7 code meaning
Third Row Left Seat Belt Pretensioner C Deployment Control
What B00E7 means
B00E7 marks the C-stage tensioner of the third row's left seat, listed after its right-hand twin B00E6. Mercedes-Benz documents it: LI54.21-P-070658 uses B00E713 when the firing pill of the left third-row tensioning retractor shows an open, in the same list as the rear and driver retractors. In that topic the remedy does not start with the tensioner but with fault-tracing the wire and reconnecting the restraint unit plugs; only a recurring fault calls for a new control unit of at least level Q4. Joyson describes this kind of pyrotechnic retractor, which can sit in the body or the seat structure. No other maker publishes B00E7. Airbag lamp on; the left third-row occupant is not tensioned.
B00E7 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of B00E7
- Airbag lamp or fixed SRS message
- No pretensioning for the left third-row seat
- Safety note: pyrotechnic device – disconnect the battery and wait before touching it; have it serviced at a specialist workshop
Common causes of B00E7
- Most likelyRaised resistance at the restraint unit plug
- PossibleLeft third-row retractor connector disturbed during trim or seat work
- Less likelyControl unit below the required level, fault keeps returning
- Less likelyRetractor squib open internally
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Third row left pretensioner cSquib circuitSRS control module
What each part of B00E7 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). |
| E7 | The exact fault in that area. |
What to do next
- Note B00E7 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 B00E7
What does B00E7 mean?
B00E7 means "Third Row Left Seat Belt Pretensioner C Deployment Control". B00E7 marks the C-stage tensioner of the third row's left seat, listed after its right-hand twin B00E6. It is a generic code, so it means the same on every make.
Is it safe to drive with B00E7?
B00E7 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will B00E7 fail an emissions test?
B00E7 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 B00E7 to fix?
Difficulty: workshop only. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will B00E7 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.