Sök
B0040
System
Supplemental Restraint (Airbag)
Scanner som krävs
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Occupant Classification System Malfunction

Understand B0040, common causes, and the right TOPDON scanner to diagnose it.

Passenger occupancy classification system fault — airbag may stay disabled incorrectly.

Vanliga symptom

  • Passenger airbag off light always on
  • Airbag warning

Typiska orsaker

  • Occupancy mat in passenger seat
  • Seat cushion replaced without sensor
  • Connector under seat

Vilken scanner behöver du?

Full-system scanner (engine, ABS, SRS, transmission, service resets)

Använd live-data och freeze frame innan du byter delar. ABS-, SRS- och U-koder kräver oftast en fullsystems-scanner.

Diagnostiktips

  • Spara freeze frame när koden först sätts
  • Rensa koden först efter att orsaken är åtgärdad
  • Kontrollera relaterade väntande koder
  • Verifiera batterispänning över 12,4 V innan du misstänker sensorer

Rekommenderade TOPDON-scannrar

Vanliga frågor

What does B0040 mean?
B0040 indicates occupant classification system malfunction. Passenger occupancy classification system fault — airbag may stay disabled incorrectly.
Can I diagnose B0040 with a basic code reader?
B0040 may set in the engine module, but related diagnostics often benefit from an enhanced or full-system scanner with live data and freeze frame.
Which TOPDON scanner do I need for B0040?
Full-system scanner (engine, ABS, SRS, transmission, service resets) See recommended tools on this page.
Is it safe to drive with B0040?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.