Wiring circuit fault finding

[ausi steve]

In trying to sort out wiring harnesses, instead of using an Ohm meter where you have to balance it so you can watch the needle to see if you have the correct wire you are chasing, make up a buzzer/bell powered by a battery. Connect across the buzzer/bell circuit two lengths of wire say 3M each with alligator clips attached at their other ends, When the alligator clips are connected the buzzer/bell will sound.
Connect one alligator clip to the wire of which you are trying to find the other end and simply touch the other alligator clip to the various wire ends till you hear the buzzer/bell operate, it save a lot of time and frustration and is great for black only wiring harnesses.

[RCK974X]

Great idea,

The better class of multimeters already have a buzzer option on their 'low resistance' settings for exactly the same reason.....

[phillpot]

Or a simple, cheap test lamp

[ausi steve]

I too use a test lamp but it requires current in the circuit which may at times not be possible or it may cause a short and fry the wires but the simple buzzer does not allow any harm to the wires whilst you are sorting out the harness.