I'm in the process of restoring a pair of Guide 6 11/16" fog lights, vintage ca. 1936-38. When I disassembled them I discovered that the sockets and the bulbs seem to be the type found in headlights, i.e., the bulbs are the type that have two contacts on the bottom and they mount with the three-prong system; the sockets have spring-loaded contacts with 2 poles and 2 wires. The wires are shot and will have to be replaced. I'm wondering why these sockets have the 2 pole/wire system rather than just one pole sockets? If I recall correctly, the last set of fog lights I restored had sockets with only one pole/wire. The wires don't look original, so I suppose they may have been replaced--am I right in that assumption, i.e., that they should only have one pole sockets and corresponding bulbs? Where would the second wire be wired in any case for fog lights? Since the lights have been totally disassembled, it will be easy to replace the sockets with those that would have been correct originally.

Thanks for your help.

Jim

Several of the fog lights have the two contact socket and will use a special two prong bulb, but the wires go one to the 6-volt hot line, and the other goes to a good ground.

Fog lights mounted on the bumper have a handicap of being grounded, thus the direct wire back to a good ground on the vehicle.

went out looked at my lights i only have one wire going to my fog light switch and the to power source the other is ground which in my case was grounded to one of the rivets(inside of housing) that held the mounting bracket to the bulb housing. i just cut off some of the bad ground wire and just added to it where necessary that way i did not have to replace the rivet

The Guide fog lamps I had on my '39 had the socket the same as a head light as you described. The one wire was used, the other (for the dual filament bulb) was cut of at the factory. The working filament was for the high beam.
What I did is hook up the "cut off" low filament wire so the fog lap could be used as a directional light. The result was fog light still functioned as before but I also had an ultra bright directional. I used a 21-32 candle power headlight bulb, the 21 CP low bean filament for the directional which was the correct load for the flasher.
From what I have seen at least the 1937-1940 GM Guide 6 11/16" fog lights were wired in this manner.

Thanks for the helpful replies. I will maintain the dual socket and thus have the option of a good ground wire or as Gene suggests.

Jim

I wired both of mine together, then connected them to back of the bucket as one wire, so both come on at the same time. Kinda like running low and high beams at the same time. They are bright.

for the pre 1938 applications this would require way more amps than the stock generator could supply.

For my '39 with the fogs being on and aiding the stock headlamps night vision was almost adquate.