Brake pads are worn. When the brake pads are worn, the brake light will blink to indicate that the pads need to be replaced. This should also be addressed immediately as worn brake pads can lead to brake failure.
Parking brake is engaged. When the parking brake is engaged, the brake light will blink to indicate that the parking brake is on. This is a reminder to release the parking brake before driving.
Brake system malfunction. If the brake system is malfunctioning, the brake light will blink to indicate that there is a problem with the brakes. This should be investigated further to identify and fix the source of the problem.