88 Ford Bronco only starts with starter fluid...?

Has 2 fuel pumps, Have checked fuel cut off switch, it is fine, checked all fuses and relays, they are fine, I have power to primary fuel pump but only register 2.4 milivolts, something other than relay or fuse is causing the pump to not get full power, It only starts if I use starter fluid. Anyone know what may be the problem, I have been over everything I can think of, cant see what I might have missed...