A mazda security indicator light flashing when the car is off is an indication that something has gone wrong with the immobilizer system. This is designed to prevent your car from starting if it detects that the key fob that controls it has been tampered with in some way, like being pressed against another object, or that it has been stolen. This system also makes sure that the key fob itself is in range of the vehicle, so that signals from other devices like phones and transceivers cannot interfere with it.
The first thing to do if your mazda security indicator light keeps flashing is to try using a different key or a spare. This should reset the immobilizer system and turn off the warning indicator light. If this doesn’t work, you will need to consult a mechanic or your car’s dealership for further help.
Sometimes the problem is with the key itself. Whenever you press the lock button, the integrated chip in the key sends a signal to the vehicle that it has been locked. If this signal is disrupted for any reason, the security indicator light will keep flashing. We recommend getting regular maintenance on your keys to make sure that they are functioning properly, which will prevent this kind of problem in the future.
Another possible issue is that the vehicle has detected that a new key has been used. This can happen if you have lost or misplaced your original key. To solve this problem, bring all of your keys to an Authorized Mazda Repairer. They will be able to reset the electronic codes in all of your remaining keys and the immobilizer system.