I have finished my stand alone harness and have all the wires ready for a fuseblock and to splice into the trucks original wiring but I'm having issues with one wire/circuit.
My alternator has a four pin plug with three wires, two of them (brown and grey) go to the pcm
But one is now cut and I'm not too sure what to do with it.
It is dark blue in cavity A on the alt plug.
Circuit 5668 engine on signal.
It was clipped from the c100 connector on my harness.
From what I have discovered it goes to the SBA supplemental brake assist.
I'm assuming is just an engine on signal for that module, and I can de-pin it from my alt plug and remove it with no issues.

Anyone have any more insight on this circuit?
From what I read on the internets its not too common, as a matter of fact I can only find that circuit on 05 harness schematics, mines an 03 dbw.