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<DIV><FONT color=#000000 size=2>At this point there's no-body doing this
??...I'm currently working on a programming</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT><FONT size=2>method, but it'll be a while
before I've got this one figured out. This is one of the first</FONT></DIV>
<DIV><FONT size=2>truck "flash" computers.</FONT> </DIV>
<DIV><FONT size=2>Lyndon.</FONT> </DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 solid 2px; MARGIN-LEFT: 5px; PADDING-LEFT: 5px">
<DIV><FONT face=Arial size=2><B>-----Original Message-----</B><BR><B>From:
</B>Dr.Acacio <<A
href="mailto:aortiz@w3ti.com.br">aortiz@w3ti.com.br</A>><BR><B>To: </B><A
href="mailto:gmecm@diy-efi.org">gmecm@diy-efi.org</A> <<A
href="mailto:gmecm@diy-efi.org">gmecm@diy-efi.org</A>><BR><B>Date:
</B>September 14, 2000 9:41 AM<BR><B>Subject: </B>SS10
Help<BR><BR></DIV></FONT>
<DIV><FONT face=Arial size=2>Hi all </FONT></DIV>
<DIV><FONT face=Arial size=2>Could anyone give some helpto change the
calibration for </FONT></DIV>
<DIV><FONT face=Arial size=2>a GM Truck SS10 95, with Delco black box</DIV>
<DIV><FONT face=Arial size=2> 16166340</FONT></DIV>
<DIV><FONT face=Arial size=2> 86BABBK 43212W P5</FONT></DIV>
<DIV><FONT face=Arial size=2> service
16193495.</FONT></DIV>
<DIV> </DIV>
<DIV>Thanks in advance</DIV></FONT>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>>Hi,<BR> > My best guess
is: maybe, but you would have to try it. I am not
too<BR>>confident.<BR><BR> I would need to know what year the
S-10 is from.<BR><BR> You need to know that GM did not
standardize their communication protocol. <BR>They made changes to the
commands and responses nearly every model year. We<BR>found that the
93 LT-1 responses are quite different from the 94/95
LT-1<BR>responses. And of course the 96's are OBD-II. So this
would imply that the<BR>S-10 might have a different communication
protocol.<BR><BR> You also need to know that if you go
down the 'remove the flash' route,<BR>that GM has swapped some of the lines
between the flash and the CPU. If I<BR>remember correctly, they
swapped 3 of the address lines. So by simply reading<BR>the data in
the flash, you will see garbage. It can be decoded, but again,<BR>that
is more work.<BR><BR> From what I've seen from the
software inside a number of GM PCM's, they<BR>tend to re-use their code
whenever possible. Sometimes they reuse the actual<BR>source code, and
sometimes they just reuse the ideas and the code looks<BR>similar but
different. Unfortunately the location in the flash where
some<BR>specific code (like for the speed limit) moves around alot from PCM
to PCM.<BR><BR> Also unfortunately, the speed limit change you
need is probably just 1 or 2<BR>bytes that need
changing.<BR><BR> We really only understand the 94/95 LT-1 PCM's
in detail. There are people<BR>out there that understand the earlier
models pretty well, and some that<BR>understand the later models pretty
well. I'd suggest you look into the GMECM<BR>mailing list (found at
diy-efy.org) or the DIY-EFI mailing list (same<BR>address). There are
ALOT of experts there that might be able to answer your<BR>questions, and
maybe even provide some tools to help. I have to believe
that<BR>someone on this list has the code for the S-10 truck, and might be
able to<BR>point you at the location in memory that needs to be
changed.<BR><BR> You can try our software and see if it works,
but you would have to<BR>purchase a cable.<BR><BR> Thanks for
finding that error on the web page. We will go fix it.<BR><BR>Dave @
carputing.com<BR><BR><BR>"Dr.Acacio" <<A
href="mailto:aortiz@w3ti.com.br">aortiz@w3ti.com.br</A>>
wrote:<BR><BR>> --------------------------------------------- <BR>>
Attachment: <BR>> MIME Type: multipart/alternative <BR>>
--------------------------------------------- <BR>Could be possible to use
your program ( PCMReader.exe)to read a Brazilian S-10<BR>truck which has no
VIN number????<BR>Since you know the protocol to talk with the GM flash ECU
there are any<BR>chances to develop an editor for Brazilans trucks?? I know
you are involved in<BR>the OBD II version of the editor, and probably has no
time do do others<BR>projects, but we need here any tool to remove the speed
limit...<BR>Thanks in advanced....<BR>PS<BR>1.Another way to read would be
removing the flash and read it in a<BR>programmer...<BR>Do you think that
the speed limit routine will be completely different from<BR>each GM flash
ECU type????<BR>2. There are an error in your web page, the total
tamount to buy cable and<BR>software will be from 195 to
US$295.00 not
245.00.....<BR>Regards.<BR></DIV></FONT></BLOCKQUOTE></BODY></HTML>