I have a 2017 L5P 2500 that won't start (I know) because the lift pump isnt turning on. I"m not sure what relay 1 or 2 is for the lift pump but all fuses seem to be fine and I have bench tested relay 1 and it seems to be fine. I'm gonna add also that the fuel gauge isn't working either. I don't seem to be getting a keyed 12v to the relay either. But if I bypass the relay with a piece of wire still no pump. From what I've been able to figure out both the lift pump and fuel gauge are controlled by the fppm ? The truck shut off while suddenly while driving luckily on a back road and I could tell I hade no fuel pump. But when the roll back dropped it in the driveway it fired right up and did so another 2=3 times after that. But now it's completly dead. I've read alot about the silverado ground issues which I've checked and all of those seem to be fine. Can anyone help with a wiring diagram for the lift pump and the fuel system control module so that I can try to narrow the problem? Or does anyone know of any common isses with the L5P that would cause this ? (grounding ????)
tonkatruckbuildr
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What fuel system service are you talking about? Filter change? If it worked before the filter change, and it didn't after the filter change, something happened. What button?
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You received a message telling you that the fuel pump module driver is bad. Just obtain a new one and replace it.
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Did you have the module(s) programmed? From what I can see, they require programming.
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The charges are clearly out of order without any question.
Once the FPCM was found to be passing the proper current to the motor, it should have taken almost 5 minutes to find that there was a short that needed to be repaired.
It doesn't take long to R&R a driveshaft. This is what ALLDATA shows for the driveshaft labor for my 2008 long bed
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Once the FPCM was found to be passing the proper current to the motor, it should have taken almost 5 minutes to find that there was a short that needed to be repaired.
It doesn't take long to R&R a driveshaft. This is what ALLDATA shows for the driveshaft labor for my 2008 long bed
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