That explanation is WRONG, I tried it to knowing it was faulty. You cannot get potential difference on two ends of the same wire!

I beat my head against the wall then Jim (fbody) had a suggestion to try the second wire on the brown reg wire. it pinned the guage, so I tried the green one. BINGO. Works perfectly.

If your guage is good, do a continuity test on either ends of your Black and White wires to pinpoint the faulty one...