An ice pick type test light connected to a source of battery voltage can be used to test for wiring continuity without actually powering up a circuit. That way, the resistance of the light bulb in the tester prevents over current and blown fuses, etc. even under "dead short" conditions.
Jerry

"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
Love your enemies and drive 'em nuts!