Interfacing with GM '96-'97...

[David A. Cooley]

Dave,
The 96 and up vehicles use OBD_II for the interface.  No more ALDL
interfaces being used per federal reg's.
The problem with OBD_II is that there is some security built in for
accessing some of the parameters.
Best bet to start for info is the SAE.  Their handbook, HS-3000 covers the
whole spectrum of OBD_II from the interface, contents of the comm packets
and even the scantool interface.
There are several places on the web with OBD_II interfaces fairly
inexpensive that may do what you want and are not limited to one vehicle.
http://www.obd-2.com/
http://www.obdii.com/

Take care,
Dave


-----Original Message-----
From: Greathouse, David (GEP, WAS) <David.Greathouse at gepex.ge.com>
To: 'gmecm at efi332.eng.ohio-state.edu' <gmecm at efi332.eng.ohio-state.edu>
Date: Monday, March 22, 1999 1:11 PM
Subject: Interfacing with GM '96-'97...


>All:
>
>Hello, I am extremely new to this list but not to microprocessor
electronics
>OR Motorola assembler...
>
>I searched for a FAQ for this group but came up empty. That said, I would
like
>to ask for indulgence for my apparent ignorance and rehashing of anything
that
>might be "old stuff"
>
>I currently own a '96 GMC Suburban and a '97 GMC Sierra both have
"flashable"
>engine management systems (350 Vortech).  I would like to reprogram some of
>the functions so that I can remove the top-speed limiter, change shift
points,
>etc...
>
>I guess I would like to know where to start with building an interface for
the
>ALDL connector so that I can hook up a computer.  Does anyone have any
>information on an interface?  Is there a place I can go to download the
info I
>need?
>I know that what I would like to do is possible.  Hypertech sells a
programmer
>for my vehicle for $350..  The bad thing is you can only use it on ONE
vehicle
>at a time.
>
>TIA
>
>Dave G
>
>