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Thread: Overwrite HPT custom OS

  1. #1
    Lifetime Member limited cv8r's Avatar
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    Default Overwrite HPT custom OS

    I understand a PCM with a HPT custom OS will show up as locked. Question is can I overwrite this with a full flash from Efilive. This is a LS1 PCM.
    It's all good until it goes "Bang"

  2. #2
    Lifetime Member macca_779's Avatar
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    Quote Originally Posted by limited cv8r View Post
    I understand a PCM with a HPT custom OS will show up as locked. Question is can I overwrite this with a full flash from Efilive. This is a LS1 PCM.
    No you can't mate. HPT changes the key automatically when applying their custom OS on LS1's. It's a pain in the arse.


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  3. #3
    Lifetime Member GMPX's Avatar
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    It's amazing how many HPT users are not aware of that 'feature'. Not real good when there is shops out there who don't lock PCM's (knowingly).
    I no longer monitor the forum, please either post your question or create a support ticket.

  4. #4
    Lifetime Member limited cv8r's Avatar
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    So I guess I will be sending another parcel to GMPX.
    It's all good until it goes "Bang"

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    Lifetime Member GMPX's Avatar
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    Check it first, you never know, because now that I think about it, I don't think the auto lock is mandatory, the user has to Disable it, rather than Enable it.
    I no longer monitor the forum, please either post your question or create a support ticket.

  6. #6
    Lifetime Member limited cv8r's Avatar
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    I tried to read this PCM already,I get the unrecognised or locked PCM message,use alt keys will show a seed but end up same result. This car has previosly been tuned mafless, that's why I'm assuming its either locked or HPT custom OS.
    It's all good until it goes "Bang"

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    if it is HPT custom os for LS1B they have a different seed key algo for the custom os and a different one again for actually locking it. So to any other software its always locked. To their software it can be locked or unlocked.

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    you can tell by the os number if its one of their custom os

  9. #9
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    Can the GM dealer flash it back to stock?

  10. #10
    Lifetime Member GMPX's Avatar
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    Quote Originally Posted by kangsta View Post
    if it is HPT custom os for LS1B they have a different seed key algo for the custom os and a different one again for actually locking it. So to any other software its always locked. To their software it can be locked or unlocked.
    That doesn't make sense, it's either locked or it's not. I hear it all the time from people that the tuner says he didn't lock the PCM but they can't read or write to it. What would be the point of using a different seed/key algo on a custom OS if their (anyone with HPT) can unlock it?

    Quote Originally Posted by Ryan W. View Post
    Can the GM dealer flash it back to stock?
    No.
    I no longer monitor the forum, please either post your question or create a support ticket.

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