ECM Flash

Discussion in 'Electrical' started by 90FXRS, Oct 4, 2010.

  1. 90FXRS

    90FXRS Junior Member Contributor

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    What might cause the ecm to return to a previous setting? Does this make any sense? Flash it and it goes back to the previous setting when you cycle the ignition.
     
  2. rancid

    rancid Active Member

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    are you turning the ignition off for long enough?? thats all i can think of
     
  3. 90FXRS

    90FXRS Junior Member Contributor

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    Uhhhhh....not sure. Is a couple of minutes long enough?
     
  4. Hoople

    Hoople Account Removed

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    How exactly and what are you using to change the settings. What settings? MM ECM?
     
  5. 90FXRS

    90FXRS Junior Member Contributor

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    Guess I should have put a little more info out there. Bike has an issue with stalling at an idle. Cleaned the iac, as I did with mine, still does it. Good friend works for a dealer and came over. Plugged in the lappy and the vin is not recognized and neither is the speedo. This is with Harley dealer's service laptop.

    Flashed the ecm, which I don't think is the stock one. The part number on the back is not listed in parts catalog for the bike. Afterwards when we checked it.......still not seeing the vin or speedo.

    Correct me if I'm wrong......if the ecm does not recognize the speedo, when you slow down it has no idea how fast you're going so the injection system might flood the motor.

    Ecm replacement for the old guy?
     
  6. rancid

    rancid Active Member

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    a couple of minutes is more than enough, from memory the early efi bikes arent speed dependant, the 07? and up has the speedo linked in. bit of a hard one
     
  7. Hoople

    Hoople Account Removed

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    That will not happen. The speed of the bike is irrelevant to injector pulse width. Pulse width & frequency is a function of engine load and RPM. Stalling at idle can be caused by a number of things. For it to be a "bad" ECM would be very remote.
     
  8. 90FXRS

    90FXRS Junior Member Contributor

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    Here's the results. Changed the ecm to a new unit, part number 32534-05C. The old powercommander is not compatible with newer ecms. Called them and they weren't sure if they would play together or not. Tried a couple of things and the result is a new ecm and sert. Put it on the dyno......110 horse and 109 torque. Rode the bike for about 75 miles.....never missed a lick. Took it back into the shop and the system is seeing everything as it should. Vin, speedo are recognized and no errors in the system.
     
  9. NEWHD74FAN

    NEWHD74FAN Experienced Member Retired Moderators

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    Check the old ECM part number, your new one is a rev C...so hardware mods were likely added, if old one was 05_ rev. Suppose the dealer might have a service bulletin why the rev change, but it would be safe to assume that was the problem.

    The new ECM version (p/n 32534-05C is at least the 4th version (-05, -05A, -05B preceeded it).

    CROSS REFERENCE dated January 2004:

    p/n 32772-01 Use on ’01 to ’04 Big Twin EFI ECM’s (when obsolete - use 32534-05)
     
    Last edited: Oct 10, 2010
  10. 90FXRS

    90FXRS Junior Member Contributor

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    Old ecm number is 32772-01.