Quote Originally Posted by steveo View Post
i thought it only got power in the 'start' position
Turns out it's both START and RUN. E4 is RUN only.

Quote Originally Posted by steveo View Post
it seems that a handshake is required. we proved that by making the ECM provide the correct response at which point the CCM became bus master and started the F0 polls. i -think- what you're likely seeing in the key-off state is the ECM isn't alive so it's not responding to the CCM.
Interesting. You're probably right; I would have to check my logs on my '95 while running experiments to see if that is indeed the case. I mean, I assume it is since you already got it working thanks to kur4o's hack, but yeah. I could confirm I suppose.

Definitely seems like a security-related thing; again this handshake was not present in the 90-91 and was only added in 92 and later. And since I only have the original 1990 documentation, well, there's that.