truck broke down today

[ShhhhhDougsHere]

P/B is your power wire for the fuel pump.
B is the ground wire for the fuel pump.

Like @Curious Hound said right now let's focus on the fuel pump working and not working.

We're not really worried about the fuel sender which tells your gas gauge how much gas you got.

However yes your OHMs reading will be the Y/W wire get the red probe of your multimeter.
And the B/W wire get the black probe of your multimeter.

Y/W is your sender reading wire.
B/W is your ground wire for the sender.

 

[Curious Hound]

I agree with @Curious Hound no matter what he says it's always right.

Oh, no it's not. I don't know it all and I DO make mistakes. But it's good to concentrate on the problem and not get sidetracked.

 

[Curious Hound]

If you only have 6 volts on the P/Bk wire, that's a problem. We need to figure out why. What is your battery voltage at the battery?

 

[ShhhhhDougsHere]

Okay @dashhho
We want you to focus on just the P/B wire and the B wire.
Which are your power and ground for the fuel pump.
Red probe for the multimeter on the P/B wire and black probe for your multimeter on the B wire.

 

[dashhho]

If you only have 6 volts on the P/Bk wire, that's a problem. We need to figure out why. What is your battery voltage at the battery?

11.7V at the battery. I put a charger on it...its prob a bit low with all the testing.

 

[djfllmn]

11.7V at the battery. I put a charger on it...its prob a bit low with all the testing.

Okay so thats not terrible. My next step, unless you already did this. Inspect the wiring harness for any damage, corrosion, etc. Check out South Main Auto on Youtube. He has some great videos on this topic

 

[dashhho]

Will do.
Any easy way to hotwire the pump in place? Do the two wires mean I need 20V to turn the pump? Can I just use the one 10V wire, and then ground the other pin?

 

[ShhhhhDougsHere]

I believe you need 12 volts on the power wire and a good ground.
If you do hot wire it do not I repeat do not leave it hooked up very long at all because you can burn it out.

 

[Curious Hound]

Will do.
Any easy way to hotwire the pump in place? Do the two wires mean I need 20V to turn the pump? Can I just use the one 10V wire, and then ground the other pin?

That yellow wire with 10volts on it is probably on a smaller fuse. I wouldn't use that. Besides, it should have 12 volts on it. We'll get to that later.

You need battery voltage (12volts nominal) and a good ground to test the pump.

 

[dashhho]

I will take the battery out and try it with the pump directly

 

[ShhhhhDougsHere]

I agree with @Curious Hound you should have at least 12 volts.
If you have a battery charger, charge the battery tonight and start fresh tomorrow.

 

[dashhho]

Tried the pump with the battery and no go.

 

[Curious Hound]

New pump.

 

[ShhhhhDougsHere]

Sorry to read that @dashhho .

 

[Uncle Gump]

I've had a power probe for at least 25 years.

Its the first tool I grab for electrical diagnostics. I loaned it out and came back broke. The next day i bought a new one. I also have a cheaper version that's in my truck box.

Clamp it on the battery... it has a 15 foot lead and you have power and ground in your hand with a flick of a switch. And... it's better then a test light. I'm lost without it.

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