If there's enough of a short to blow the fuse, there's enough to make a light burn bright when inserted in place of the fuse. If it's in series with another bulb, it burns dim, or not at all. It simply limits the current in the shorted wire low enough to prevent damage while the technician searches for the source of the short. I use a small peanut bulb like is used for dashboard illumination with wires and alligator clips or blade terminals attached so I can plug it in place of the fuse. Once the shorted part or wire is located, the bulb goes out- - - -it loses its ground. This method is convenient when a short must be traced the whole length of a vehicle and meter leads simply aren't long enough to reach both ends of the wire.
Jerry

Last edited by Hotrod Lincoln; 04/13/2010 8:54 PM.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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