1993 Nissan 300ZX Logo
Posted on May 17, 2011
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Not hearing fuel pump coming on. Checked relay, ok, Have power (using test light) to far right (standing behind car) wire (there are 5 wires counting the ground). I think I should have power to the white/blue stripe wire (second from left). I also checked the fuse on the block right by the battery, it looks ok. Is there another fuse under the dash I might be missing? Thanks,

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  • Master 4,803 Answers
  • Posted on May 17, 2011
Anonymous
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Your fuel pump is powered by the GREEN fuse link in the fuse link holder. If you have 2 terminals (both WHITE/BLACK wires) at the fuel pump relay that is HOT all the time (even with the key OFF) then this fuse link is OK. There are no other fuses to be concerned with.

There is also a "Fuel Pump Control Unit" located on the left rear quarter panel, behind the "B" pillar. (See Picture)


Not hearing fuel pump coming - dttech_77.gif

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  • Nissan Master 6,988 Answers
  • Posted on May 17, 2011
Ronny Bennett Sr.
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There will be two wires hot,one for the sending unit,for the fuel gauge,and the other for the fuel pump.Now when turning the key to on,there will be 12 volts going to the fuel pump,for only 1.5 second,then the relay (under the hood)will click off,and there will be no power to the fuel pump.So,you need to make sure ,one of the wires on the fuel pump assembly is hot all the time with key on,and the other wire only lights the test light momentary(1.5 second).The fuel pump is the most likely cause for the problem you are having.

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No power to fuel pump.

check your fuses under the dash and under the hood
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