Body, Comfort and Passive Safety Codes

B codes for airbags, seat belt pretensioners, climate control, central locking, power windows, alarm and lighting. Many of them do not turn on the check engine light but a warning light of their own.

Most basic code readers cannot access these modules: you need a multi-system scan tool. Airbag codes call for extra care, because the system contains pyrotechnic charges that can deploy while you work on it.

Most searched codes in this system

• Resistance out of range in the driver or passenger airbag circuit.
• Seat occupancy sensor faults.
• Seat belt pretensioner circuits.
• Power window and door lock motors.

What to check first

1. Disconnect the battery and wait the time the manufacturer specifies before touching an airbag.
2. Check the connector under the seat, which often comes loose when the seat is moved.
3. Use a scan tool that can reach the body module to read the full code.
4. Never measure an airbag directly with an ohmmeter.