I don't know a whole lot about electronics, so bare with me here.
I need a switch that is activated by 12v, kinda like this:
12v is applied to the THINGY, the THINGY connects 2 wires for 1-2 seconds then releases. Keep in mind 12v was not disconnected from the THINGY at any point in time... When power is disconnected, nothing happens, but the THINGY is ready to do it all over again.
Now, is that something that exists already? If not, would it be easy enough to throw it together with basic soldering skills?