GM ignition key readers

[Terry Martin]

Ron Tyler wrote:
> 
> Terry,
> 
>        Thats interesting that you say they eliminated #1 resistor. I
> (recently) purchased a factory srv man for a '95 Camaro/Firebird and it
> list's all 15. Do you know when they dropped it? BTW, the manual does
> state it is PASS-key II. In looking through two service manuals one
> difference seems to be that PASS-key II has a much more in-depth
> diagnostics abillity.
> 
>    rt

Rule 1. Engage brain before typing. :>)
Sorry, the statement that they eliminated the #1 resistor was
misleading. They went to a different lock arrangment which uses the
longer double sided key with the small oval head, which is the same
configuration as the PASS-Key III, which incorporates the transponder in
the key head, doing away with the useless resistor arrangement. Just to
really bugger things up, the retained the PASS-Key II electronics on
most vehicles, and used the embedded resistor with the longer double
sided key. It's that arrangement that I believe they dumped the #1
resistor and went with 2-15. The old single sided key still uses all
fifteen, although there are variations within variations. The only way I
can tell for sure is to look at the vehicle key. Then there's
PASS-Lock...

The diagnostics are more or less the same with PASS-Key & both
variations of PASS-Key II. I don't think even GM knows when and which
vehicles they made this mess with, but it started around '94-'95 on a
guess, as running assembly line changes. 

Terry