Unless the Air Flow Meter (AFM), Cam and Crank sensor senses air flow/movement, it will turn off the fuel pump off after a couple seconds.
Basic fuel pump wireing. The ECU grounds the relay, which turns on the pump. The jumper pin does the same thing. So if the pump runs when jumped, it is not a relay or pump problem (the output of the relay). By default the issue is in the control side of the relay (ECU, Sensors, Wires)
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