Fault code B1505 – a step-by-step guide to diagnosing and fixing it

Error code B1505 is displayed and the check engine light is on - what does this mean?

The DTC B1505 is a manufacturer-specific fault code that is recognized by the OBD system and typically indicates problems with the airbag system or the body electronics. This trouble code mainly occurs in Ford vehicles and indicates faults in the airbag control unit or related safety systems.

What can cause this fault code?

• Defective airbag sensor in the driver's area
• Damaged wiring to the airbag system
• Loose or corroded plug connections
• Faulty airbag control unit
• Defective belt tensioner sensor
• Broken ground wire in the airbag circuit
• Damaged crash sensor
• Defective airbag coil cable in the steering wheel

What symptoms occur in parallel with fault code B1505?

• Airbag warning light: The airbag indicator light lights up continuously or flashes in the dashboard
• Deactivated airbags: The entire airbag system may be deactivated
• Seat belt pretensioner problems: Automatic seat belt pretensioners may not work properly
• Electronic malfunctions: Other body electronics may be affected
• No error messages on the display: Additional warning messages regarding the safety systems

How to fix the problem of fault code B1505?

• Repairing fault code B1505 requires a systematic diagnosis of the airbag components.
• Read out the airbag system with a professional OBD scanner and document all fault codes, then replace defective sensors or control units in accordance with the manufacturer's specifications
• Check and clean all plug connections in the airbag system and replace all plug connectors if they are corroded or damaged
• Measure the wiring between the airbag control unit and sensors with a multimeter and repair damaged cables or replace complete wiring harnesses
• Remove the airbag spiral cable in the steering wheel and check for breaks; if defective, replace the complete spiral cable set
• Check the crash sensors at the intended positions and replace with original parts if they malfunction
• Program or replace the airbag control unit if other components are functional but the eobd code still exists