912 Headlight question

[lenball]

The car is a 1969 912

I lost the right headlight, thought it had burned out.
It works fine on High beam but will not light up on low beam, so
I naturally replaced the bulb, no luck, still works in high, but not
on low. So I pulled out the Volt meter, un-plugged the lamp
and low and behold, 12v on low beam. So I plug the bulb back in
and nothing. I decide to check the voltage with the bulb plugged
in and 0 volts read on the meter.
Unplug the bulb and I get 12V. I switched bulbs with the left one
which works and still no low beam, but it works on high.... Any
ideas?? Is there a relay that could be causing this?

Let me know what you think.

lenball@sbcglobal.net

[adot]

Maybe its the ground wire. You say 12v at low side, but where is the neg. side of the meter, car ground or the plug ground? Maybe High beam is getting ground somehow from low side. Just a thought

GoodLuck
Brett

[lenball]

Thanks Brett,

I am checking the groud at both sources, the chassis and the plug and get the same results, 12V on the low beam ciurcut without the bulb plugged in but nothig when it is, but i will check the grounds again, could have always overlooked something...

Thanks again,

Len