Completely normal for the light to flash when engine is off and car parked. I had this same question answered on this forum when I was a newbie years ago!

 

It might help with casual car thieves. They see the flashing light knowing it is a security system active, and they move on to a less secure target. Of course this would probably not deter any professionals that want your vehicle.

 

My car RAV4 security light is blinking. What is the problem

 

There is no problem. The blinking light simply means the engine immobilizer system is active, i.e. the car cannot be started unless an authorized key is present.

 

I too had the security light come and it was never on prior.