[VAC] Re: 7 Pin Wiring Electrical Connector

["C. Petrich" <cpetrich@xxxxxxxxxx>]

I too am trying to make trailer lights work ('66 Caravel).  Testing with the
wire colors that you sent, and using a 12V battery (table shows wires
connected to the positive and negatives sides of the battery), I'm observing
the following:

 Positive /  Negative  /  result
________________________
 green  / white  /  nothing
brown / white / nothing
red / white / nothing
brown / black / both L and R flashers light
red / black / both L and R flashers light
green / black / nothing
green / trailer frame / nothing, except circuit tester on the neg side
lights up
brown / trailer frame / nothing, except circuit tester on the neg side
lights up
red / trailer frame / nothing, except circuit tester on the neg side lights
up

>From this I have several questions:
1. it seems that the ground wire (white) is not functional, but it seems
unlikely that each one of these lights would form a poor ground (I've
cleaned bulb contacts).  Where does the trailer shell attach to the white
wire?
2. The back up wire (black) seems to light things up, or serve as a ground,
but there are no back up lights for the trailer.  (seems confusing).  Why is
there a back up circuit?
3. When attaching the green, brown, or red wires to the pos side of the
battery, and the negative side through a circuit tester to the frame, the
circuit tester lights up but not the lights.  Any ideas?

In advance, thank you for any help that you can offer!  (I'm stymied).

Christian
'66 Caravel