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Splicing in Flat-Four Trailer Plug

May 16th 2020, 3:06am

Hello friends.
I'm adding a flat-four plug in my 92 Astro.

In every other vehicle I've done
this, there was a white (neutral),
green (right blinker/brake),
yellow (left blinker/brake),
and brown (tail).

On this Astro, there is light green,
dark green, yellow, and brown.
I've isolated the dark green, yellow,
and brown to their respective circuits.

My question is this:
Is the light green wire my neutral?

Thanks in advance!

Re: Splicing in Flat-Four Trailer Plug

May 16th 2020, 5:04am

Huckleberry;
I am not sure just what might be on the '92.
I think the light green wire was for B/U lamps on my 1998. To be sure, try using it as the ground ( negative wire) for testing the other three leads. It will not hurt anything, and if it is not a ground, you might get get various lamps dimly responding, or maybe nothing noticeable.
If you use that light green wire as the ground wire ( and if it is in fact the Ground wire lead) then a test lamp ( or voltmeter if you have one) on each of the other wires should operate as expected.

For reference:
On my '98, the ground wire is a significantly larger gauge, and is WHITE .
My RH Turn wire is DK.GREEN, LH Turn is YELLOW, Park/tail lamps is BROWN.
I also have a High Center brake lamp that is a smaller gauge white wire.
The Backup Lamps wire on my van is Lt. Green.
There is also a large ORANGE wire in the bundle, which is for use with trailer brakes, but it is often not hooked up at the front of the vehicle ( taped up in the wiring near the under dash fuse box).
I hope this helps you.
Rod J

Re: Splicing in Flat-Four Trailer Plug

May 16th 2020, 3:52pm

93 Wiring-Trailer.jpg

Re: Splicing in Flat-Four Trailer Plug

May 16th 2020, 7:18pm

Huckleberry wrote:I've isolated the dark green, yellow,
and brown to their respective circuits.

That is all you need from the harness.

Huckleberry wrote:My question is this:
Is the light green wire my neutral?


You make your own ground to the chassis.

Re: Splicing in Flat-Four Trailer Plug

May 17th 2020, 8:06pm

Thanks for the replies!
So based on that diagram and the other info,
I won't do anything with the light green wire,
and I'll run the white wire from my plug directly to the chassis.
Thanks again!
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