2003 5.4 EB Fuel Pump Relay

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Bedrck47

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For one expy girl tried to repair the fuse box and failed Can't say why as I have no idea how it was done or if she used an old relay. Then she listened to someone that told her a fuse box for an 04 nav would work and it did to some degree. After having been thru this problem many times with other members I sent her some information and even a comment from a truthful seller on e-bay that knows the part numbers have to be the same and Also from my experience that the 03 uses two different fuse boxes I have not heard back from her since Typical of many new members.

Now you need to decide if you want to take my advice or continue to search the forum or google for someone else's advice. The PCM doesn't not vary the voltage to the fuel pump.

Get yourself a new fuse box or one from a salvage yard and hope its in working condition or replace the relay on the board

If you have tried the jumper and the expy is running you now know the relay is faulty.

Sorry for being blunt
 
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CertusExpo

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I'm not ignoring your advice. It's spot on.
I definitely will ensure that the replacement fuse box part number matches.

The ideas I have with a standard but heavy duty relay is a long-term improvement over OEM if I can figure it out. Especially the ability to adjust the voltage (flow) real-time using the digital readout on the potentiometer.
 

Bedrck47

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In the post that you referred to me the OP has an 05 expy The 2nd gens have a fuel pump relay that is soldered to the circuit HOWEVER the 03 and 04 years use the same fuel pump motor circuit THE 05 and 06 have the addition of a fuel pump drivers module that controls the fuel pump motor The 03 and 04 is controlled just by the relay.

The operation of the relay and the fuel pump drivers module are not the same

But both systems had their own problems the FPDM was subject to failure due to corrosion and would leave you high and dry at least with the relay a jumper would get you running but if the pump was the problem better put on your walking shoes
 
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In the post that you referred to me the OP has an 05 expy The 2nd gens have a fuel pump relay that is soldered to the circuit HOWEVER the 03 and 04 years use the same fuel pump motor circuit THE 05 and 06 have the addition of a fuel pump drivers module that controls the fuel pump motor The 03 and 04 is controlled just by the relay.

The operation of the relay and the fuel pump drivers module are not the same



I missed this detail. Which is a very important one. Thanks for the catch Bedrck.
 
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Bedrck,

Quick question. Would you happen to know what size sockets and/or tools will be needed for the uninstall/install?
 
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