Reading the crank and OBDII (Camaro)

[m_mcdonald at marx.ENET.dec.com]

Steve Ravet <sravet at bangate.compaq.com> writes:

> I skimmed this document [the EPA document about OBD-II}, all I really
> got out of it was that the EPA is requiring manufacturers to make
> available to the general public all emmissions related repair
> information that they make available to their dealers.  (available
> not implying free).  It also seems to require that reprogramming of
> the ECM be allowed, and the information to accomplish that must be
> made available.  But the information can be made available indirectly,
> in the form of a device that can reprogram the ECM, without actually
> revealing how to reprogram it.  Did I miss anything?

The EPA document forces manufacturers to make available all their
emissions-related repair information that, in turn, contains *much*
performance-related information.  It's not free, but it's not the
dozens/hundreds of dollars per manual that the manufacturers would
probably like to charge and it is easily available.  Many related
companies, such as Helms in Detroit, have toll-free numbers and
accept plastic.  These companies must ship the technical information
within a day or two of receiving an order.

Apparently limited reprogramming of a vehicle's ECM is allowed so
that technicians can look for problems and verify that they've been
solved.  I don't know much about reprogramming.  My goal is to be
able to *read* the messages moving among sensors, the ECM, and
actuators.  I have no desire to *write* or *alter* these messages.  

<snip>

About "available service manuals, TSBs, training kits, etc." -- these
are what manufacturers make available to technicians at dealerships,
so I assume they contain information that's valuable to skilled
do-it-yourselfers such as members of this mailing list.


Marll McDonald   KB1AGM
m_mcdonald at marx.enet.dec.com