
Diagnostic procedure

No.3 there is a malfunction in the system even though abs warning light,
brake system warning light, dsc indicator light and tcs-off light do not
illuminate
No.5 dsc*2 operates frequently/dsc does not work correctly*2: dsc indicator
light goes on and off while dsc operatesMazda 6 Service Manual: Intermittent concern troubleshooting
Vibration Method
1. If malfunction occurs or becomes worse while driving on a rough road or
when engine is vibrating, perform the steps below.
Note
There are several reasons vehicle or engine vibration could cause
an electrical malfunction. Some of the things to check for are:
...
Mazda 6 Service Manual: Smart Brake Support (SBS) (Some models)
The Smart Brake Support (SBS) system alerts the driver of a possible collision
using a display and warning sound if the radar sensor (front) and the Forward Sensing
Camera (FSC) determine that there is the possibility of a collision with a vehicle
ahead while the vehicle is being driven at abo ...