i removed all relays and still showed continuity to ground through the terminals of the fuses with battery disconnected.

 

the top is only one layer of the fuse box. but what you can see looks pretty clean.

 

I separated all layers and inspected individually

 

Getting closer to a solution. I have disconnected the harness at the rear bumper. The thick red wire had short to ground. So I followed the harness to the engine bay to find the connector between the battery and master cylinder. Once I disconnected the harness I no longer had short to ground on the red wire at the rear of the truck.

I’m attaching two pictures showing the two harness connections that I have in plugged. the two male ends of the connector still have short to ground. The female ends do not. Any idea where these travel in the harness?

Also, BEFORE IT GOT TO THIS POINT when it was just dying intermittently. When I disconnected the trailer light harness it would turn over but not start. Is there a ground in the harness on that connection that would somehow keep from powering the fuel pump? Once I plugged in the harness to the bumper, it would fire up. Just thought of this and figured there may be some info there to help solve this problem……

 

well at least now you have ruled out some of the issue. now you need to find out what number that connector is and see what the pinout is and what it feeds. then see where it can rub. a common place there are wire breaks or rub are around transmission all the way up to the back of the engine / intake manifold area.
but you would have to find out exactly what that plug feeds.

 

Does anyone have a pin out for the BCM connectors, the connector going in to the top of the fuse box, the two connectors in the bottom of the fuse box, and the red/purple wire going in to the top of the fuse box?

 

Nevermind guys. I found the problem. Wire harness to the trans rubbed the bell housing and was shorting out.

I took my voltmeter and set it it to audible OHMS and connected to the ignition fuse. As the meter was steadily beeeeeeeeeeeeeeeeep(ing) I proceeded to wiggle every part of the harness till the beep stopped. That’s how I found what part of the harness was shorting out.

I am currently trying to disconnect and pull the harness up to the engine bay to fix wires and loom. I’ll follow up with pics.

 

Nice work! Way to be persistent in getting that payoff of knowing what the problem was and the eventual solution.

 

yup that was my thought. some sort of chaffing in the trans tunnel area.

 

Cut and spliced 2 wires with heat shrink butt connector, wrapped with 3m rubber wrap, then wrapped in electric tape. BACK IN ACTION!

appreciate the help and input of the group.