No error codes with my EProm

[Keith Lund]

I have a 1227730 ECM in a 81 vette.  I do not have the VATS hardware so 
order a stock 91 vette eprom (16159800), turned the VATS bit off, updated 
the checksum and installed the new chip.  The engine runs, but my eprom 
will not flash out the error codes.  If I install the stock eprom the 
codes flash out, but of course it complains about VATS.  I have verified 
my eprom and it has the contents I want.  Does anyone know why one chip 
would flash out codes and the other not?

TIA very much.

Keith

Curious:  I was wondering what that small circuit board next to the eprom 
is/does.
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