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JCA
August 31st, 2006, 01:57 PM
Hi, just woundering if any one can give me a few pointers on pulling the flash chip out of an aussie ls1 as my customers pcm has been locked be another tuner, i want to unlock the pcm and read the tune from the flash chip, i have an eprom reader etc, also if any one can provide details of where to buy some spare pcms at a resonable cost. regards JCA
TAQuickness
August 31st, 2006, 08:37 PM
Send a PM to Wait4Me.
Delco
August 31st, 2006, 08:38 PM
Hi, just woundering if any one can give me a few pointers on pulling the flash chip out of an aussie ls1 as my customers pcm has been locked be another tuner, i want to unlock the pcm and read the tune from the flash chip, i have an eprom reader etc, also if any one can provide details of where to buy some spare pcms at a resonable cost. regards JCA

If you are in Aus I also offer a unlocking service.

Chip doesnt need to be removed off the board
JCA
September 1st, 2006, 11:34 AM
Hi, Whats Invovled ,how Is It Locked?, How Do U Un Lock It, Do You Read The Flash Manually, And Then Erase It?. What Do You Charge, I'm Keen To Learn To Do It Myself, But It Depends On How Hard It Is. Regards Jca
Delco
September 1st, 2006, 12:31 PM
Hi, Whats Invovled ,how Is It Locked?, How Do U Un Lock It, Do You Read The Flash Manually, And Then Erase It?. What Do You Charge, I'm Keen To Learn To Do It Myself, But It Depends On How Hard It Is. Regards Jca

It is the same as any hacking , learn how to bruteforce your way in and its done.

Much the same way as learing how to break into the PCM to allow programming , remember the PCM is locked by GM , you just need to work out how it was locked and how to unlock it
GMPX
September 1st, 2006, 02:58 PM
If you want to pull chips off you need a programmer worth about $1K AUD that will support the flash chip used in the LS1, most of the $300 programmers will not, how to tell, does it have a 48pin socket?

You also need some pretty reasonable soldering skills.

Cheers,
Ross
ringram
October 10th, 2006, 07:42 AM
How many combinations of keys are there FFFF? (ie) 65535? In which case brute forcing 65K keys wont take long. Just have to figure out how to talk to the PCM and recognise when the valid key is entered.
Sorry for digging this up.
Just got some customers with locked hpt tunes.. Im pretty certain they are stock OS, just that they are locked. They want efilive. Any PM info will be treated in confidence :D
ace68
October 10th, 2006, 09:05 AM
SHHHHHHHHH DAVE might be watching
ringram
October 10th, 2006, 10:05 AM
Im against PCM locking, though I can understand if you are an insecure type you might want to put obstacles in others way to slow them down. However I think its wrong to lock someone out of their own house. How can they change the tune or replace it when its locked? Who cares about the actual tune thats in there, tunes are straight forward once you know how, some just take more time than others. Its preventing access to something that is not rightfully theirs to lock that bothers me. Blah blah rant, rant.
Delco
October 10th, 2006, 12:18 PM
Im against PCM locking, though I can understand if you are an insecure type you might want to put obstacles in others way to slow them down. However I think its wrong to lock someone out of their own house. How can they change the tune or replace it when its locked? Who cares about the actual tune thats in there, tunes are straight forward once you know how, some just take more time than others. Its preventing access to something that is not rightfully theirs to lock that bothers me. Blah blah rant, rant.

What you need to remember is that the tune is locked from the factory , it is only by working out the seed/key routine that you are able to unlock it via the work of efilive , locking only stops the people that dont have the experince to work it out themselves - especially with mail order tunes.

I used to add some txt into the binary much like GM did to identify my tunes , its amazing where that txt has turned up in supposidly qualified tuners tunes :bash:

As for unlocking you need to try about 65536 possible combinations and the pcm needs to be reset after every one
Maggie
October 11th, 2006, 03:15 AM
quick question:
If you are going to use a new EFILive tune or custom OS... wouldn't it be easier to reinstall new software over the locked program? Or, am I misunderstanding and it is the PCM's access that is locked?
On the few "locked mail order tunned" PCM's that I have redone I have had no problem with reinstalling a current version of GM software and starting over with 'clean' un-piddled with software.
joecar
October 11th, 2006, 04:41 AM
Maggie, you're correct: the lock only prevents reading, it doesn't prevent overwriting.
carneb
October 11th, 2006, 07:55 PM
Maggie, you're correct: the lock only prevents reading, it doesn't prevent overwriting.

Does that mean that no matter what method is used to lock the PCM, you can still overwrite it?
ringram
October 11th, 2006, 08:10 PM
Oh ok, I missunderstood. In which case thats fine. Im happy with being able to overwrite the whole thing with a full reflash.
As carneb says, can someone confirm this 100%. I cant test on mine as I have the road runner PCM which works differently.
1998ws6
October 17th, 2006, 06:01 AM
If the locking alters the seed key, then how can it be overwritten?

Ryan
ringram
October 17th, 2006, 07:28 AM
Write a new seed over the top. Dont try and read anything, just write is my guess
wait4me
October 17th, 2006, 07:52 AM
IF the pcm is locked you cant read or write to the pcm.
joecar
October 17th, 2006, 08:34 AM
IF the pcm is locked you cant read or write to the pcm.Oh, you can't even write over the top...?
joecar
October 18th, 2006, 02:48 PM
Oh, you can't even write over the top...?So what do you do if if have a locked PCM and want to overwrite it with your own tune...?

Edit: hmmm.... I remember a very old thread dealing with this...
wait4me
October 18th, 2006, 02:50 PM
The only options are for you to pull the computer apart, Make a brute force password program, get a new computer, or get the person that unlocked it to either unlock it for you, or give you the key.
joecar
October 18th, 2006, 08:50 PM
quick question:
If you are going to use a new EFILive tune or custom OS... wouldn't it be easier to reinstall new software over the locked program? Or, am I misunderstanding and it is the PCM's access that is locked?
On the few "locked mail order tunned" PCM's that I have redone I have had no problem with reinstalling a current version of GM software and starting over with 'clean' un-piddled with software.Maggie, I was wrong, looks like access to the PCM is locked.

Joe
Maggie
October 19th, 2006, 02:22 AM
Hmm, well I had a 'locked' pcm from an exchange laying around so I thought I would give it a go...I didn't have any problem with the install of new 'Dealer software'. The PCM had a re-write from Z-industries in it. I couldn't get into the PCM with either Edit or EFiLive. Teck II reported a soft ware error. I replaced the software & all seems to be good.... ??? I suppose that the PCM may have not been actually locked but the tables had been moved or re-aranged and could not be read by EFI Flash scan or Edit?