B0040
Front Crash Sensor Communication Error
2006-2011 BMW 328i 3.0L I6
Critical SeverityBodyGeneric (SAE)
Description
Communication loss between the front crash sensor and the airbag control module over the dedicated sensor bus.
Symptoms
- Airbag warning light on
- SRS fault stored
- Frontal protection may be degraded
Common Causes
- Damaged sensor bus wiring
- Faulty front crash sensor
- ACM internal fault
- Connector pin damage
Diagnostic Steps
- Scan SRS codes for communication faults
- Inspect sensor bus wiring
- Check connector pins
- Test sensor power and ground
- Attempt ACM-to-sensor communication test
Repair Notes
Repair sensor bus wiring or replace front crash sensor.
Related Codes
Other Body Codes
- B0001Driver Frontal Stage 1 Deployment Control
- B0002Driver Frontal Stage 2 Deployment Control
- B0003Passenger Frontal Stage 1 Deployment Control
- B0004Passenger Frontal Stage 2 Deployment Control
- B0005Driver Knee Airbag Deployment Circuit
- B0006Passenger Knee Airbag Deployment Circuit
- B0007Rear Left Side Airbag Deployment Circuit
- B0008Rear Right Side Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
- B0011Driver Side Airbag Deployment Circuit Open
B0040 on Other Vehicles
Common Questions
What does code B0040 mean on a 2006-2011 BMW 328i?
B0040 stands for "Front Crash Sensor Communication Error". Communication loss between the front crash sensor and the airbag control module over the dedicated sensor bus.
What are the symptoms of B0040 on a BMW 328i?
Common symptoms of B0040 include: Airbag warning light on, SRS fault stored, Frontal protection may be degraded.
What causes B0040 on a 2006-2011 BMW 328i?
Common causes of B0040 include: Damaged sensor bus wiring, Faulty front crash sensor, ACM internal fault, Connector pin damage.