Hello, new to the site. I have a 1989 Corvette that just put itself into "Limp Mode." I last put in led headlights into the car and a day or two and it ran completely fine. Then all of a sudden I was going to head to a concert with it; started car, flipped up the lights, DIC lights come on like usual, unset the E Brake, threw it into gear and started driving. I noticed that the Radiator fan kicked on as soon as I started the car but didn't think nothing of it until when I started to accelerate and the car had a tremendous loss of power.
Next day I have tried using the paperclip method to short the obd1 connector on A-B, nothing. SES Light and radiator fan is constantly on and didn't blink whatsoever when I was trying to short the plug. I've ordered a OBD1 Chevy scanner tool just incase if it was operator error when it came to the SES light not blinking and reading out the code #.

My question is, if the car doesnt give a Error code, is my ECM shot? Do I have to purchase one of those Moates G1 proms or what should I do? I'm completely lost if the car doesnt throw a code. I'll know for certain this coming weekend whats wrong, fingers crossed, if the car throws a code. If not, I need some guidance on what to do and how to reset the ECM so the car isn't limp mode.
Yes I have a FSM but it has seen greater days.