76 XLH generator lamp

[hdhikaru]

Hi Experts,

the gen lamp on when hi rpm , off when low... something wrong with gen or reg or both? anyway to instant check?
tks Shin

[Lyle Manheimer]

Check your battery terminal voltage when revving the engine, should be some where around 13.8 volts to 14.2 volts. If I remember correctly there is a diode in the indicating light circuit and it may be faulty or wired in backwards.

[otis71]

I believe the light comes on not only if current is too low but also if too high. If so I would think the voltage regulator should be checked.