What's going on here?!?
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From: Central California
What's going on here?!?
I still haven't resolved my fuel delivery issue. The pumps don't cycle, even when the DLC is grounded. The inertia switch isn't tripped, and the relay seems okay (it clicks when the DLC is grounded). According to Haynes, the next step was to check the fuel pumps for voltage. The aft harness is a pain to get at without dropping the tank or pulling the bed, and the forward harness read 6.7 volts.
What is this? There is battery voltage on the forward pump--which has never worked since I've had the truck--but it's not the usual 12 volts. I'd be inclined to think the forward pump is bad, but decided to run this by the experts before shelling out $255 for a new pump.
Whatever the case, this is the last straw. I will never again own a vehicle made after 1975!
What is this? There is battery voltage on the forward pump--which has never worked since I've had the truck--but it's not the usual 12 volts. I'd be inclined to think the forward pump is bad, but decided to run this by the experts before shelling out $255 for a new pump.
Whatever the case, this is the last straw. I will never again own a vehicle made after 1975!
Fleet Owner
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From: Easton,Ks
Originally Posted by Navy Jet Mech
What is this? There is battery voltage on the forward pump--which has never worked since I've had the truck--but it's not the usual 12 volts.
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From: Central California
Originally Posted by subford
What 12 volts is it then?
Fleet Owner
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From: Easton,Ks
Originally Posted by Navy Jet Mech
Whoops! I phrased that wrong...I should've said that I expected the meter would read about 12 volts (key on, engine off) and got 6.7 or so instead.
You used a DVM to check for voltage with no load and read the flux field form other wires.
You need to use a TEST LIGHT with a bulb that loads the circuit and you will get no light (zero volts).
With the key on and that tank selected you will get zero volts unless you ground pin #6 or short pin #2 to pin #6 of the VIP/DLC test connector.
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I need to ground pin 6 or short pin 2 to pin 6 before I turn the key on and take a test light to the red and black wires. If the light comes on, the pump is bad, and if not, I need to perform circuit checks. Is that correct?
Fleet Owner
Joined: Aug 2005
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From: Easton,Ks
Originally Posted by Navy Jet Mech
I need to ground pin 6 or short pin 2 to pin 6 before I turn the key on and take a test light to the red and black wires. If the light comes on, the pump is bad, and if not, I need to perform circuit checks. Is that correct?
Here is a diagram of your system.
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From: Central California
Thanks for the diagram--very helpful! I could use the rest of 'em, too, as Haynes manuals aren't as comprehensive as they used to be--where would I find them? I think I have another 12V bulb laying around, so I'll hook that up sometime when it's not so dang hot outside and let you know how it goes.
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I have had issues reading voltage on the pumps remember voltage is cut off at a certain pressure in the line pull out one of the lines up front and stick in bucket then turn on pump and check for proper voltage hope it helps
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