Topic: Quick electiracal question

[noisebomb]

Just curious, when you are dealing with a bulb socket, which of the two wires is the positive, and which is the negative.  One wire comes from the center of the socket, and the other is attached to the outer wall.  see poorly made diagram to see what I am asking.

Thank you all...
Johnny

[tlbranth]

pretty sure the centre is + and the outside is - (ground)

[mystic_1]

pretty sure the centre is + and the outside is - (ground)

That's the common convention, but really light bulbs themselves don't care which is positive and which is negative.  Some lights, however, ground the socket directly to a chassis ground rather than a harness ground, so in that case it matters.

mystic_1

[noisebomb]

Okay then, specifically, the bulbs inside the speedo and tach.  Brown wire comes from the center, green wire is soldered to base.  I just want to know because I am trying to maintain factory colors on the wires, so it will be easier to troubleshoot compared to factory wiring diagram.

[mystic_1]

Green is the standard color for ground in these harnesses, brown is positive.

mystic_1

[noisebomb]

Thank you so very much, sir.  Should have these things put back together tomorrow.  Will post pics.