my jeep cherokee has a in tank fuel problem?

[blinky]

i have a 1995 jeep cherokee sport with an in line six cylinder.the key switch shorted out so i changed it,everything works fine now but the in tank fuel pump dosent.i get fire to the unit but the pump still dosent run.i took the pump and hook a hot wire to it and it will run ok,but when i hook up the harness it wont pump.im 73 yrs old and have a wife with cancer and i cant afford to pay a shop.im really up a creek since it our only transport.right now im using my daughters car.