OBD2 code B0401: Anti-theft/alarm system
Anti-theft system fault.
Detected Root Component
Body Component
Observed Symptoms
- Faulty central locking
- Dashboard errors
- Unable to start
Possible Causes
- Faulty BCM module
- Defective sensor
- Incorrect module configuration
- Damaged wiring
Tools Required
Interactive Diagnostic
Answer each question to calculate your diagnostic score.
No steps available.
Diagnostic Result
Score threshold guide
Was this diagnostic helpful?
Parts likely to be the cause (Boîtier fusibles / BSI)
Boîtier fusibles / BSI
Photo d'illustration : Boîtier fusibles / BSI
© DTC-Logic.com
Click on an image to enlarge
Frequently asked questions about code B0401
What does code B0401 mean? ▾
OBD2 code B0401: Anti-theft/alarm system. Anti-theft system fault.
What are the symptoms of code B0401? ▾
Code B0401 may cause: Faulty central locking, Dashboard errors, Unable to start. The intensity of these symptoms varies depending on the vehicle and driving conditions.
What causes code B0401? ▾
The most common causes of code B0401 are: Faulty BCM module, Defective sensor, Incorrect module configuration, Damaged wiring. A proper OBD2 diagnostic will pinpoint the exact cause.
Is it serious to drive with code B0401? ▾
Code B0401 has moderate severity (Warning). Short-term driving remains possible, but a prompt check is recommended to prevent worsening.
How do I fix code B0401? ▾
Start by reading the code with an OBD2 scanner, then follow the interactive decision tree on this page. Priority causes to check: Faulty BCM module, Defective sensor, Incorrect module configuration, Damaged wiring. Difficulty: Easy · Estimated time: 30-60min.