Question about this Sun tach

[blown motor]

Can someone identify which is the signal wire that goes to the tach. Black is ground and white is the light. I would think that red is power which leaves the bare wire for the signal. Shouldn't the signal wire  be insulated? Green? This doesn't make sense.

[Katfish]

Coil wire can't be bare, that in non-insulated wire must be ground.

[blown motor]

But it touched the black wire to negative on the battery and the white to positive and the light worked. So I figured black was the ground wire.

[anlauto]

You'd think so....did you open up the cable further up and see if the green wire is bare all the way up ?

[blown motor]

Correction!!! The bare wire IS ground. When I touched the black wire to the post the bare wire must have been contacting metal somewhere making a ground and do the light came in. I just redid things being more careful about the loose wires. So black must be the signal wire.

[Kowal]

That is not a factory wire harness from Sun.   Take the back cover off and you will be able to figure out the signal and ground and see where the light is.   Make a new harness for yourself, you don't know what was done with that one