Sorry, another fuel pump issue (complicated)

[Enoch Jolliffe]

99 Suburban 5.7. Just bought this non-runner, but only 140K miles. Replaced intake gaskets (big problemo there), it's back together and realized that my FP isn't priming (cycling) with key on. I have confirmed ECM B fuse is good, relay was swapped with one from another running suburban of mine- no change. Jumped FP relay pins 87(B1) / 30(A3) which does activate the pump,  runs pumps and sounds fine (will verify pressure when it comes to that). So my FP, fuse, relay, and wiring to the pump all seem to be good, seems that it's not getting a go signal from ecm? Not sure where to go from here, I can follow instructions but am not a whiz with digging into a wiring schematic, so any assistance appreciated. I will probably try another ecm tomorrow if I can find one. Another possible clue is my volts gauge seems to be dead with new batt, haven't noticed any other electrical equip that is inop at the moment, don't see any "passlock" warning lights currently. . Thanks for any assistance.