Contacted the ECU rebuilders at SIA electronics who fixed the N14 Cummins ECU for me on Joe.
Fuse and relay checking next, then I need to find a better continuity and resistance check table than I've found to go through the harness between the ECU/PCM/TIPM to check can bus things and supply pins. that'll be a thrill. Might try to get it in the shop, I don't think I've tried to move this one from its tail with the forklift before with the lunette ring.