PCM is locked

[bgray]

hello all,

long story short is that my truck was tuned 3 or 4 years ago with either efi live or hp tuners, not sure which.


fast forward 4 years and i have efi live, just went to go upload a tune and my ecm is locked by the previous tuner. how in gods green earth do i unlock it so that i can tune my truck? i have no contact to the previous tuner. Is it possible to get it unlocked, or do i pretty much need a new ecm?


if i need a new ecm, will anything in my tune need changing, or simply swap it in and reflash with my tunes settings?

fyi its a 1999 gmc sierra, with a lq9 engine swap

[minytrker]

cheaper just to buy another pcm

[Taz]

Hello bgray,

Your PCM may have been locked by the previous tuner - that is one possibility. However, sometimes when attempting to read a PCM with the incorrect settings - a "PCM locked" message will appear.

In V7.5 when you select the "Read" function (Green arrow) make sure you selected the correct Controller from the drop down menu (LS1B Gen III 99-08 PCM), check the "Try Alt Keys" box, and use the "Check Status" function. If this is successful, then click on the "Start" button at the bottom.

Also try a similar approach using V8. If you still fail to connect / read the PCM then odds are it is indeed locked.

I have received the "locked" message before (from a non-locked PCM / ECM) by inadvertently having selected the wrong controller, and / or not using the Alt Key function.

Also, sometimes "noise" (interference from other modules / aftermarket electronics) will prevent a successful read (though not usually with an LS1-B PCM). Attempting a "bench" read would definitively rule out this possibility.

Good luck ... hopefully it is not locked.


Regards,
Taz

[bgray]

Thanks for the response. I varified and tried both of those ways, its defiently locked by the other tuner. So i yanked a PCM out of a junk 2000 Yukon I have and did a whole reflash with OS and its working.

thanks for the incite