If your Fuel Pump Control Unit is giving you trouble or you suspect it is, you can bypass the it as a temporary solution to get you home if it fails while you're out and about (as it usually does), or to diagnose the FPCU as the root of a non-starting/poor-running condition. The FPCU changes voltage by limiting the ground-side of the signal, so bypassing the FPCU simply requires a direct ground connection to the line which would otherwise be limited, supplying battery voltage to the FPCU under all conditions.

Please note that while many owners have driven on their cars for as long as a year with the FPCU bypassed, it should be done as a temporary solution, as this can put excess strain on the fuel pump and fuel pressure regulator.

Original writeup from Aus300ZX.com.

This article is for the 2-seater. For the 2+2 (four seater), see FPCU Bypass (2+2).

Bypassing the FPCU

Parts Needed

  • A couple of feet of electrical wire.
  • Two male spade connectors.
  • Three female spade connectors.
  • One electrical eyelet.

Tools Needed

  • Scissors, wire strippers, crimpers, general electrical tools.
  • Philips screwdriver
  • 10mm socket/ratchet.

Procedure

  1. Remove the parcel tray behind the rear seats (8x Philips screws?). It may be necessary to remove the interior panels to either side of the parcel tray. This can be done by pulling up from the center.
    image004_fpcu2st.gif
  2. Disconnect the large white connector near the cover on the left (driver's side).
    • The left cover houses the fuel pump assembly. The right cover houses the fuel level sending unit for the gauge.
  3. Create two short male-to-female jumps and one longer female-to-eyelet jump, as shown in the photo below.
    image005.gif
  4. Jump the two "end" pins together. Connect the long lead to the "corner" pin on the fuel-pump side of the connector.
    image006_fpcu2st.gif FPCU_bypass_2-seater.png
  5. Connect the eyelet to any nearby ground.
  6. Enjoy <3

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