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Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Tue Sep 27, 2011 5:52 pm
by uknomeprk
I hope so, that guy is an ACE in my book I've read a lot of stuff he's posted.

4x VPW is very good to know :D . I hope your right and I probably just went on a search tangent, also a little frustration is setting in; albeit no response from A1 has rattled my cage. I messed with the IFR and still get nothing. BUT no rest for the weary this all needs to get hammered out.

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Tue Sep 27, 2011 10:24 pm
by vn5000
Antus is right ,ls1 are not can protocol,its j1850vpw,and i have read also that if 4x writing is to fast it will change back to 1x.I think i read this in efilive somewhere.The software i have will write a cal in about 30 sec at 4x,so at 1x it would take 2 mins which is not a problem.
Maybe try changing the vin no. first .This is done at normal speed ,pcm unlocked ,writing using mode 3B.Looking at a port monitor log of this procedure ,the elm should handle it no worries.

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Thu Sep 29, 2011 7:25 pm
by vn5000
Ah Ha
I just used my elm 327 v1.4 to program / change the vin . :afro:

You need to unlock your pcm
Set the elm for long messages
Enter mode 28 (optional)
Set the header as 6C10F0
Then 3B01(NEW VIN) six bytes in ascii
3B02
3B03
All up 18 bytes the first one is 0x00
Switch ign off for 15 sec
You can program one line only as well.

If we can work out the vats relink flag you will be able to swap pcms from one vehicle to enougher. :thumbup:

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Thu Sep 29, 2011 7:29 pm
by delcowizzid
keep up the good work guys

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Fri Sep 30, 2011 10:41 am
by uknomeprk
vn5000 you rock :punk: that's a huge step for all of us. I been coding VB like a madman and i'm going to do some serious testing with GMOS Saturday I expect things to go well, screenshots to come.

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Fri Sep 30, 2011 11:08 am
by The1
good stuff guys :thumbup:

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Fri Sep 30, 2011 4:49 pm
by dimented24x7
I havent actually seen anything directly that requires the use of 4x AFAIK. Since there is no native program in the PCM to handle a full reflash (code must be sent, and then request that the PCM execute the code) you can use any method you like once the PCM has handed over execution control. If your just doing block by block reflashing the 1x may be a viable, but slow, option to do a reflash.

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Sun Oct 02, 2011 11:30 am
by uknomeprk
I've said before that I'm not much of a coder, but after an afternoon of debugging, head scratching, trial, and error; finally managed to get a semi functional GMOS running. It's pretty exciting to see it work, but no one hold their breath on a release date. There's still a lot of work to be done and lots of PCM controls to be understood. Anyway here's a screenshot.

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Sun Oct 02, 2011 1:46 pm
by Holden202T
:thumbup:

Re: Open source GM OBD2 flash tool using a ELM327 device

Posted: Mon Oct 03, 2011 8:08 am
by uknomeprk
I forgot to say this last night, Dimented24x7 welcome to the thread. I've said it before I'll say it again I learned a lot from your posts, thanks. Now, down to business; can you or anyone suggest a really good free BIN file reader for 96+ GM Bins.