Another F.I. question

[phat46]

Recently i asked a question about the fuel injection setup on a friends v-8 conversion in an S-10. i have another one  now. It seems that my friend couldn't get power to the fuel pump relay so he wired it direct to the key switch. The truck starts and runs, but he'd like to wire it correctly. He noticed that it had an open space in the fuse panel marked EPM-B. There is also a fuse marked EPM 1 with a fuse in it. He put a fuse in the EPM-B holder and it provided power to the fuel pump relay, but then the truck would not shut off with the key switch till he pulled that fuse! He also tells me that there is no power OUT of the relay and he has tried four different relays. Any ideas why the truck won't stop when this fuse is in? My guess was a backfeed from the first wire he ran to the fuel pump, but he says there is no power coming out of the relay, so i don't know how it could backfeed though an open relay......