If the Smart City Brake Support (SCBS) is operating, the indicator light (red) flashes.

Smart City Brake Support (SCBS)
Collision WarningMazda 6 Owners Manual: Engine tune-up
IGNITION TIMING INSPECTION
Note
Ignition timing is not adjustable.
Ignition timing verification requires WDS or equivalent.
1. Turn off the electrical loads.
2. Warm up the engine as follows.
(1) Start the engine.
(2) Maintain the engine speed at approx. 3,000 rpm until the
cooli ...
Mazda 6 Owners Manual: Stopping The Smart Brake Support (SBS) System Operation
The Smart Brake Support (SBS) system can be temporarily deactivated.
When the Smart Brake Support (SBS) system is turned off, the Smart Brake Support
(SBS) OFF indicator light turns on.
When the engine is restarted, the system becomes operational.
NOTE
If the Smart Brake Support (SBS) system ...