by jspbtown » 29 Sat Aug, 2009 10:46 am
Thinking more clearly now..darn brother-in-law!
Blinkers and horns were the last things that clicked with me.
Believe it or not the ground actually comes through the bulbs. In the bulb itself the case is grounded. When you supply power to the bulb, the reaction between the + and - is the heating of the little coil in the bulb. This collision of + and - basically is a controlled short. It glows because that is how its designed.
But if you think for a moment that the - is traveling to the little coil, then it makes sense that when no power is supplied to the bulb, that the - power continues to travel through the little coil, into the wire that provides the + and all the way back to the switch. So, when you activate the switch, the - charge actually continues back towards the flasher.
Because the flasher has + to it from the fuse block, its waiting for a - charge to start working. Flip the blinker switch, the - charge races toward the flasher, it completes the circuit, transfers power briefly, and then in what is a controlled overload, breaks the connection for a second. A second later, it cools, and the connection is made again for a second, when it breaks agains. And so on, and so on.
This is where the flasher gets its - charge.
So in my clearer head this morning I bet that the - on the flasher goes toward the switch.
Ohh...one more thing. If you have an alternator are you making provisions for the alternator light? You need on.