L83 swap - fuel pump control module

Hi guys

I have an issue about the fuel module harness wiring, everything is fine and connected to the ecm, pressure sensor is connected everything is good except there is no power in PIN8 in the connector which is the fuel supply voltage wire that I should connect it to the positive wire of the fuel pump.

So the car doesn?t start because the fuel pump is not working because there?s no power from the positive fuel pump wire from the module.

I checked the wire and the plug for cracks and it?s fine, I?m using new control module and sensor.

the ecm shows 2 codes

1- secondary fuel pump circuit is high - P0232
2- ISO/SAE reserved - P023F

It seems like the fuel pump have its own signal because when I turned my key on I found a signal in the positive fuel pump wire. Maybe because of the old relay system

Pump im using is aeromotive 340

please help

Quote:

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Originally Posted by Nawaf

It seems like the fuel pump have its own signal because when I turned my key on I found a signal in the positive fuel pump wire. Maybe because of the old relay system

Pump im using is aeromotive 340

please help

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Going to have to clarify this last paragraph, but it sounds like you're swapping the L83 into something else? If so you might be better off skipping the fuel control module and turning the low side fuel system into a return style fuel system with a fuel pressure regulator to maintain feed pressure for the high pressure pump.

I'm running this pump with the fuel control module so it will work but I'm not sure what you mean by signal on the positive fuel wire? Also, check your ground, that CEL sounds like an open circuit which means you have a bad connection somewhere in the power or ground section of your fuel pump loop. There is no signal, per say, to the pump, just a PWM voltage. When you key on you should hear it do the normal prime sequence, does it twice on these if I remember correctly. But as I said, double check your wiring.

Quote:

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Originally Posted by Harlech

Going to have to clarify this last paragraph, but it sounds like you're swapping the L83 into something else? If so you might be better off skipping the fuel control module and turning the low side fuel system into a return style fuel system with a fuel pressure regulator to maintain feed pressure for the high pressure pump.

I'm running this pump with the fuel control module so it will work but I'm not sure what you mean by signal on the positive fuel wire? Also, check your ground, that CEL sounds like an open circuit which means you have a bad connection somewhere in the power or ground section of your fuel pump loop. There is no signal, per say, to the pump, just a PWM voltage. When you key on you should hear it do the normal prime sequence, does it twice on these if I remember correctly. But as I said, double check your wiring.

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First of all thank you for your response

No actually I have the l83 and I?m swapping from the return system style into the FPCM.

I have test light the positive fuel pump wire from the module and there is no power in that wire to feed the fuel pump.

My car started for 15 second and it stalls and never started again.

Quote:

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Originally Posted by Nawaf

Hi guys

I have an issue about the fuel module harness wiring, everything is fine and connected to the ecm, pressure sensor is connected everything is good except there is no power in PIN8 in the connector which is the fuel supply voltage wire that I should connect it to the positive wire of the fuel pump.

So the car doesn?t start because the fuel pump is not working because there?s no power from the positive fuel pump wire from the module.

I checked the wire and the plug for cracks and it?s fine, I?m using new control module and sensor.

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I am kind of having the same issue in an L83 swap, except the FPCM is totally dead and can not be detected by HPT. From what I have found so far, the new modules come completely empty (no software) from GM. If your FPCM is new and unprogrammed that may be the issue.

What’s crazy is in the gm tis reprogramming service there is no fpcm on there to select. All my brand new controllers work fine. Hptuners never reads a gen v fpcm as a separate device. All the settings for the fpcm are on the engine ecu

Quote:

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Originally Posted by vannatta20

What’s crazy is in the gm tis reprogramming service there is no fpcm on there to select. All my brand new controllers work fine. Hptuners never reads a gen v fpcm as a separate device. All the settings for the fpcm are on the engine ecu

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Yes HPT can not read it but should be able to detect it and add stock FPCM data in the file. In my case it does not detect it and I can not see the FPCM specific tables either. I tested with a used module also and no luck. No priming with ignition and I can not control pump from manual controls in scanner. Not sure what the issue is here, if it is tuning or wiring related. VATS and starter diagnostics are disabled. This is a 2016 L83 with 6L80E.

Maybe you could confirm wiring? I have this connected on the swap, cant see anything else needed based on the wiring diagrams but I may have missed something.

FPCM Connector:
Pin 1 1940 Battery positive
Pin 2 5660 Signal from ECM X1 pin 44
Pin 4 7493 Serial data to ECM X1 pin 36
Pin 5 7494 Serial data to ECM X1 pin 37
Pin 6 439 Ign run/crank voltage
Pin 8 120 Fuel pump pos
Pin 9 2150 Chassis ground
Pin 16 7444 Fuel pump neg

Pin 7 5985 acc wakeup should not be needed with ign on?

Help is really appriciated

Is VATS 1 and 2 DISABLED? if you don't have VATS 2 that will be a problem too
clint

Bad news if you are running. 2016 os. The 2016 os will not work in a swap. I have tried about 5 different 2016 computers and none of them will make any power. If you have this issue you will need a flash to a swap friendly os.

Accy wake up is not needed. I don’t think these fpcm modules work like the old ones. Even my snap on scanner can’t detect it. It works fine and I can program through hptuners but only through the e92 fuel settings. My fpcm setup was tested this weekend with a 500 mile road trip and work perfectly. I now install them on all the gen v harnesses I work into standalone.
https://youtu.be/CPfTJLDi5Sk Here is a video showing the setup

Quote:

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Originally Posted by vannatta20

Bad news if you are running. 2016 os. The 2016 os will not work in a swap. I have tried about 5 different 2016 computers and none of them will make any power. If you have this issue you will need a flash to a swap friendly os.

Accy wake up is not needed. I don’t think these fpcm modules work like the old ones. Even my snap on scanner can’t detect it. It works fine and I can program through hptuners but only through the e92 fuel settings. My fpcm setup was tested this weekend with a 500 mile road trip and work perfectly. I now install them on all the gen v harnesses I work into standalone.
https://youtu.be/CPfTJLDi5Sk Here is a video showing the setup

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I know now why HPT will not detect the FPCM, support says it is not supported on this OS. I now have priming on the pump with the used module (will also try the new ones soon). Problem was a wiring issue, signal wire was pushed back in the connector.

When flashing to a different OS on these, what about the TCM? Will it also need to be flashed or leave it alone? Could you recommend an OS? I have done that several times on gen 3 and 4 ECMs but never a 5.

I have seen your videos, you are doing nice work on those harnesses.
Thanks
/Martin

The Gen V is just like the Gen IV in the area of programming modules. If I have the vehicle at my shop I use GM TIS reprogramming to match them up by the VIN. If a mail order situation I can do a full write on the ECU and TCM. This only works on the 6l80e. The 8l90e is an external computer is when those are mailed in I match with TIS. There is no full write on the 8l90 controller.

Thanks for the compliment! Its been a journey but finally have nailed down these gen V swaps for easy plug and play.

Quote:

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Originally Posted by vannatta20

The Gen V is just like the Gen IV in the area of programming modules. If I have the vehicle at my shop I use GM TIS reprogramming to match them up by the VIN. If a mail order situation I can do a full write on the ECU and TCM. This only works on the 6l80e. The 8l90e is an external computer is when those are mailed in I match with TIS. There is no full write on the 8l90 controller.

Thanks for the compliment! Its been a journey but finally have nailed down these gen V swaps for easy plug and play.

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I have the 6L80e. Need to finish rear end, prop shaft and brakes. Will update on how it runs as soon as I can test drive.
Thanks