It looks like from the run point on the ignition switch, the wire goes to the fuse box where it connects to fues 7, B, 5 and 6. The same connection then extends to the OVP relay and fuel pump relay. So if you get a low voltage on fuses 7, B, 5 and 6 as well as OVP relay coil terminal (15), socket terminal 3, (and likely on fuel relay terminal 15, socket terminal 9) then the ignition switch is bad or there is a short somewhere in the fuel pump or ovp relay. Make sure you do the test with fuel relay and ovp relay removed from the socket as well. If the switch really goes bad because of the load or is it bad regardless of the load, is the question this will answer. Let us know what you find.

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Saumil S. Patel