When I was checking voltage at the pump, it was on the bare pink wire coming out of the main harness, before I connected the pigtail. That was after removing the pigtail that I had connected with Posi-lock connectors. It's impossible to get my meter probe into the plastic connector plug end of the pigtail, it's a very small opening so I don't know what the voltage is now. I've looked before but couldn't find any electrical specs for the PFS-48 fuel pump. I'll try again, maybe reach out to Ford / Motorcraft.