I have a 2015 Ford f250 super duty I'm trying to figure out a problem that I'm having it has blown the fuse that's next to the battery it blew the fuse for the power running boards and I have no power to the back of the power junction box when I put the key in to try to turn it on I have no power to anything except for the HVAC and the radio I need some ideas on what the check next I have no power to BCM no power to PCM or ECU

 

Your truck is too new i don't have any diagram to show. When you say no power to BCM and PCM I would:
1) disconnect the wiring of your running boards
2) inspect all the ground points, including the battery ground cable. Your bcm and pcm get their ground from the chassis, not from the block thru ground strap. You can check for resistance (ohm meter) from battery ground to the chassis, also to the BCM and PCM ground terminals.
3) how many fusible links are there, check them all with ohmmeter or just continuity test, just not visually.

 

Dude, that's a tough one, sounds like a real pain. I know a guy who had some kinda similar issues on his old F-250, and it turned out to be a short in the main power line going to the fuse box. Have you checked the big main fuses that sit in the fuse box? My buddy said he had some weird 2022 Ford F-250 problems that seemed random, but it was just one simple bad connection. It's crazy how one thing can mess with so many different systems like the BCM and PCM. I'd definitely double check all the grounds. I remember him saying he had to pull the whole fuse box out to find it. But yeah, start with the grounds and the main wires first. Hope that helps!