Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
Is there 12V across the coil. ie. 0V one side, 12V the other. 12V on one side only tells half the story. If there's 12V across the coil and if it isn't open circuit, then it should turn into a magnet, which should then induce an alternating current in the field coils because of the wriggly iron thing bolted to the crankshaft spinning round. Getting too technical now.