White Wire for Fuel Pump Controller Install Guide
Note: If we modified your rear harness for a gas tank swap, the White wire has already been spliced in and the Fuel Controller has been installed in the rear of the car. You can ignore this document.
This guide will help with the wiring for the White wire that is the new ground for your fuel pump. You’ll find the controller underneath the dash on the passenger’s side near the door. Below is a picture of what it should look like. The White wire will run to the rear of the car underneath the backseat, but not at the fuel tank assembly itself. There will be a connector under the backseat that contains the ground wire for the fuel pump controller. You’ll cut this wire and splice the White wire into the side of the Black wire that goes to the pump through the grommet under the seat. Your White wire should connect now to the ground side of the pump. The other side of the Black wire that is cut will stay open. Take a little electrical tape or some shrink tube and cover the exposed end to help protect it from corrosion. The exposed end will not hurt anything if it touches metal since its ground.
Assuming the ECU is on (is the check engine light on?) this wire is connected as designed if the fuel pump primes and stops when the key turns to the “ON” position. If the pump runs consistently any time of the key is on, then the White wire has either not been spliced at all or possibly “T’d” into the harness instead of spliced into the Black wire while leaving the other side of the Black wire open.
Depending on the year and model of your car the connector may look a bit different, so we’ve broken them down in the pages below.
Always splice the provided White wire to the Black GROUND wire.
DO NOT splice into the 12V power wire. If you splice the White wire to the 12V power wire, the fuel pump controller will be damaged.
Watch the video below of how to do the White Wire install for 1998-2001 Impreza and 1998-2002 Forester models. Take note that the wire colors and connector type may change based on your year and model of car. Use the notes below to find the correct connector and wire wire for your install.
Do not splice at this connector.
Connector order is determined from the front side of the plug (female terminals) from left to right. The connector in the picture below is for reference on how to determine the pin location and may not match the connector in your car.
1993-1997 Impreza
1993-1997 Legacy
There is a 6-pin connector under the backseat on the driver’s side that will generally have 4 wires in it for non-emissions vehicles. For emissions-equipped vehicles, there will be 6 wires. This connector type remains consistent throughout this group of vehicles.
The location of this connector is under the back seat on the driver’s side.
The White wire will be spliced to the Black ground wire underneath the 12V power wire for the fuel pump. The 12V power wire changes color so we’ll make a note by year and model below to help you identify the correct Black wire to splice into. Remember, do not splice into the 12V power wire.
Power Wire - Blue with Yellow Stripe version:
Power Wire - Black with Red stripe version:
1993-1994 Impreza 1.8L
1995 Legacy
Power Wire - Blue with Yellow stripe on the fuel tank harness side switches to Black with Red stripe on the body side.
Splice into the Black GROUND wire (Pin 3) BELOW the 12V fuel pump power wire.
1995-1996 Impreza 1.8L
Power Wire - Blue with Yellow Stripe on both sides of the harness
Splice into the Black GROUND wire (Pin 3) BELOW the 12V fuel pump power wire.
1995-1996 Impreza 2.2L
Power Wire - Blue with Yellow Stripe on both sides of the harness.
Splice into the Black GROUND wire (Pin 3) BELOW the 12V fuel pump power wire.
1997 Impreza 1.8L and 2.2L
1996–1997 Legacy
Power Wire - Blue with Yellow Stripe on both sides of the harness.
Splice into the Black GROUND wire (Pin 3) BELOW the 12V fuel pump power wire.
1998-2002 Impreza
1998-2002 Forester
1998-1999 Legacy
There will be 2 connectors under the backseat. One that has 12 wires in it and another that has 2 wires in a White connector with a Black lock.
The wires are Black (Ground) and Black with a Red stripe (12v).
Cut the Black wire and splice the White into the side of the Black wire (Pin 2) going down to the fuel pump. You can refer to the video at the beginning of this document for these models.
2000-2004 Legacy
2004-2006 Baja
These models have a Black 6-pin connector. The GROUND wire is Black and is in the same upper row with only 2 wires as the Power wire changes colors a few times.
See below for specific model
The location of the fuel tank connector is under the back seat on the driver’s side.
2000 Legacy
Power Wire - Red with a Black stripe on both sides of the connector.
Splice into the Black GROUND wire (Pin 2) next to the 12V fuel pump power
2001 Legacy
Power Wire - Red with a Black stripe on the fuel tank harness side and switches Black with a Red stripe on the body side
Splice White Wire into the Black GROUND wire (Pin 2) next to the 12V fuel pump power
2002 Legacy
Power Wire - Yellow with a Red stripe on the fuel tank harness side and switches to Black with a Red stripe on the body side.
Splice into the Black GROUND wire (Pin 2) next to the 12V fuel pump power wire.
2003-2004 Legacy
Power Wire - Yellow with a Red stripe on the fuel tank harness side and switch to Red with a Black stripe on the body side.
Splice into the Black GROUND wire (Pin 2) next to the 12V fuel pump power wire.
2003-2004 Baja
Power Wire - Yellow with a Red stripe on the fuel tank harness side and switch to Red with a Black stripe on the body side.
Splice into the Black GROUND wire (Pin 2) next to the 12V fuel pump power wire.
2005-2006 Baja
Power Wire - Red with a Black stripe on both sides of the connector.
Splice into the Black GROUND wire (Pin 2) next to the 12V fuel pump power wire.
2003-2007 Impreza
2003-2008 Forester
For these models, there will be a single large connector of 16 wires.
The GROUND wire will be the Black wire (Pin 16) in the same row but at the opposite end of the connector from the 12V fuel pump power Black and Yellow wire.