Possible cause
WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
- Connector terminal disconnection, poor contact, damage, deformation, corrosion
- Open circuit in wiring harness between BSM control module (RH) and branch C
- BSM control module (RH) malfunction
Courtesy of MAZDA MOTORS CORP.