This is the tail/brake/turn signal socket for my 75 F250.



I am looking for the correct label for each one so I can correctly connect the new wires. For example:

Back wire = ground
White wire = signal
Red wire = brake light

As it is now, when I turn the lights on, the brake lights are on rather than just the tails. So far, I do not have the brake light switch hooked up, so the two wires for the brake lights are not connected to anything.

Thanks.

 

The black is the common ground I am sure. The other two are brake/turn(one wire) and the marker lights(the other wire).

Take the socket back out of the truck, put the light bulb in it, and take it up front under the hood. Stick the black wire onto the negative of the battery, and touch one of the other wires to the +. Take that wire off and stick the other colored wire to the +. The wire that lights up brighter is the brake/turn wire and the wire with less light output is the marker wire. Most Fords use a brown wire for the marker wire in the truck's harness, and the brake/turn will be various colors.

 

Perfect. You, sir have been a wealth of info for me.

Thank you.

 

I just learned something off number two post. If any of you have used bulb lube. I git a jar of it at a Peterbuilt dealership. It prevents electrical arks and stops corrosion from electrons. Dissimilar corrosion some buibs are copper based and dome are stainless base. Usually the bulb socket is steel. Learn something new AJ