'86 2.5L AX4 harness in my '88 4.0L BA10/5- Backup lights/TRANS fuse?

[8valvehero]

Hey gang! I'm back with another odd sort of question. I plan on researching more when I get the time, but hopefully one of the great CC minds knows what I'm after and can help me out before I start comparing wiring diagrams...

 

Build thread for background:

http://comancheclub.com/topic/42813-project-sipsey-88-pioneer-long-bed/

 

 

Problem:

 

When my '88 came to me it was in bad shape.

Real bad.

Nothing worked (not even the door) and the dash was ripped to pieces.

I've since been replacing just about everything recently with a special focus on restoring the interior back to perfect stock before the rainy NW winter rolls in.

As part of my interior restoration, I gave up on fixing the annihilated harness/panel in lieu of just replacing everything with a refreshed harness that I cleaned up from my donor '86. It went great and everything works except I noticed that there was no socket location for the "TRANS" fuse. I figured at the time that was for the automatic transmission control, until I started trying to pin down one of my final boggles: back-up/reverse lights.

 

So here's my question(s):

 

What is the difference between the back-up/reverse light systems in my donor '86 AX4 2.5L and my driven '88 ba10/5 4.0L?

Is there a known workaround for getting them to work?

 

Let it be known:

I have not tested the system very much yet because I'm not quite sure where to start even.

Usually I assume it's the simplest problem; I would whip out the multimeter and start testing from the socket forward. But this time it feels different and I don't want to waste a bunch of time chasing phantoms.

 

Thanks so much for reading and any help you can provide.

CHEERS!

 

Current pics. Don't let the exterior fool you, she runs well and looks near-perfect inside.

Just wait 'til I get the panels & bed swapped and a coat of paint on!

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[Pete M]

so your backup lights don't work?  could be a bad switch in the trans.  or corrosion inside the rear harness connector located behind the drivers rear tire.  (I've had both issues)