91 vert Lb9 auto no ses light no prime no data cranks won't start. Fine til yesterday stopped while cruising pulled over shut off and started right up ran fine to home won't start this am....ignition pink/black to ecm fine....both orange feeds to ecm dead...20 amp fuse ok..stopped at the pigtail....here's why... from one side of the pigtail is a heavy orange running back toward the firewall and next to it is the heavy red from the 20 amp fuse...now on the other half of the pigtail which makes the connection to these are two wires one heavy red coming up from the starter and a thin orange wire....in my car the heavy red coming up from the starter is connected through the pigtail to the heavy orange heading back...while the short 4" thin orange wire is connected via the pigtail to the heavy red from the fuse....but that thin short orange wire connects to nothing...yeah....seems to me somewhere in the past the feeds were changed...why it worked and why it doesn't work now has got me....before preceeding and potentially burning up an expensive component I ask for your help please...old coot here..great grandfather...but still like tweaking small blocks..apologize if posted twice..afraid haven't caught up to chat rooms yet

 

91 factory service manual..."power distribution" schematic shows the pigtail as C145. It confirms the heavy red off the fusible link on the starter cable connects through the pigtail to the heavy red going to the 20 amp fuse and from there via the heavy orange 340 circuit to the fuel pump relay, oil switch and yes the feeds to the ECM. The short light(16 gauge) wire actually comes right out of the back of the fusible link, runs to the pigtail and through it connects to the heavy orange 440 going to the fan/coolant relays.. I suspect the connections were switched when the starter and its main harness were replaced a few years back....disclaimer: amateur opinion.thanks to all reading my question.

 

Maybe

http://gearhead-efi.com/gearhead-efi...727V8TPI-5.jpg

 

Appreciate the reply and schematic....here's what it tells me
1. the "general" really varies his schematics in particular the wire colors, circuit numbers and the ecm pin connections eg. in comparing the schematic linked versus the one on page 8A-10-2 in the 1991 factory service manual the former links the red to the orange across the pigtail (C145) numbers the circuit 440 and connects to different points on the ecm....in contrast the schematic I'm using has it red to red and orange to orange, numbers the circuit 340 and connects to different pins on the ecm....
2.both the orange and red feeds are positive feeds the difference is the short orange is actually the "fusible Link" and the red is the 20 amp fuse circuit..
3. both schematics irrespective of the hookup go to the same places...either the fan and coolant relay or the fuel pump relay, oil switch, and ECM.
4. I would rather have the fast blow 20 amp fuse on the latter (ECM) and the slow blow fusible link to the former (fans) as in the 91 schematic
5.the fusible link melts inside the black plastic bulge and does not fall out and so it appears intact...have to check V at the pigtail
6.I hooked it up and yup prime ses on and purr....hope this saves someone similar problem...keep in mind though I've only worked on one Camaro and I'm sure not a pro...but I do like the sound of small block.