I already have a 12v flashing led that I intend to put into my car as dummy immobilisor warning LED. What I would also like to do is wire it up so that the LED only flashes when the cars ignition is off. ie. it stops flashing once the car has started.
My initial thought is to use a basic 12v relay with the switched igniton live supply energising the coil of the relay. With the flashing LED being fed via a "normally closed" contact of that relay, in my simply theory once the relay is energised by switching on the cars ignition the contact should open and hence stop the led flashing. My question to you educated folk is, will my idea work correctly, and if so what relay would be the best option, (I wouldnt know where to start). And is there a simpler way of acheiving the same result as in not requiring a relay etc etc.
My initial thought is to use a basic 12v relay with the switched igniton live supply energising the coil of the relay. With the flashing LED being fed via a "normally closed" contact of that relay, in my simply theory once the relay is energised by switching on the cars ignition the contact should open and hence stop the led flashing. My question to you educated folk is, will my idea work correctly, and if so what relay would be the best option, (I wouldnt know where to start). And is there a simpler way of acheiving the same result as in not requiring a relay etc etc.