can a Ford fuel pump relay power one pump and not the other

[greaseyfingers]

Doing a code check on my Ranger revealed a code - 95- Fuel Pump Secondary Circuit Failure.

Being the frame rail fuel pump is working. Does that indicate the relay is functioning, properly, even though the in tank fuel pump doesn't appear to be working.

Does the relay send 12 volts to each fuel pump through the same wire? Or, are there two seperate wires going from the relay's wire connectons to each fuel pump?

 

[adsm08]

The two pumps share a power line, and have separate ground lines. Secondary circuit usually indicates a ground circuit. I'd start there.

 

[greaseyfingers]

The two pumps share a power line, and have separate ground lines. Secondary circuit usually indicates a ground circuit. I'd start there.

Where does the secondary circuit in tank fuel pump receive it's ground?

 

[adsm08]

I'm not exactly sure. I know there is a ground wire in the harness, but I' don't know where it ultimately runs to.

 

[greaseyfingers]

I'm not exactly sure. I know there is a ground wire in the harness, but I' don't know where it ultimately runs to.

The plug connection that attaches to the relay had 5 wires going into it.

What are each of these wires for?

Does the relay only have one set of point contacts inside to transfer the 12 volt current to where it's suppose to go.

Does this relay send the power to the fuel tank's sending unit too, besides the primary and the seconday, in tank, fuel pump?

 

[adsm08]

Ignore the pump relay. You have the rail pump working, that means your relay is ok. If you look at it, there is a pink wire running from the relay, across the engine bay to a plug near the coil. That plug has 1 wire going in and 2 coming out, one goes to the rail, one goes to the tank.

The level sender doesn't "get power" in the sense that I think you are thinking it does. The instrument panel and fuel gauge get power and then it runs down line through a variable drop resistor attached to the float arm, and the amount of resistance changes voltage along the whole circuit, which determines the gauge position.

The FLI circuit grounds to the same place as the pump, but I know from experience that there are 4 wires in that plug, so I would guess they don't share a ground wire. Find some way to get at the pump (ie. take the tank out) and then do two things:

1) get your volt meter and check for continuity to ground on the black wires in the pump plug.

and

2) while you have it out, jump power to the pump and see if it runs.

You might just have a bad pump, the truck is almost 25 years old.