Pete 579 no crank no dash powerup

[Lonestar10]

My dad's new truck a 2015 pete 579 was fine on Sunday when I fixed the engine programming was working fine. Today they go to start the truck and the dash doesn't lite up and it won't crank. But if you put key in run and jump the starter engine starts and runs but still no cecu.

They installed an apu shutdown wire to the ignition and I think this is the problem source.
Which I told him not to install in the first place and just install a run/stop toggle switch but I'm not his longtime friend and mechanic what do I know.

But in case anyone has other ideas ied like to hear em if this isn't the case.