White Hat, I have a very similar issue with my 1994 Ocean with 8v92's. Have ddec 2 system. I would start boat and let her warm up. After 20 -40 min or so, controls would suddenly go to neutral and low idle. I could not reset engines via active station as red light would go out. No codes or anything on control heads. I would shut engines down, wait 2 seconds and restart. Same thing would happen now at 10 min. Repeat process and it would go to emergency mode every 2 - 3 min. If I turned system on but did not start engines, it would stay on for days. As soon as I started engines, the emergency mode process would start. I did not loose power to my control heads. I went so far as to only run one engine at a time. Found out that my issue is related to the starboard output side from the ERIM. I had sent mine back to Sturdy where they bench tested. They could not duplicate my issue. I also interchanged the CSIM's and active control units(did not fix issue). I even swapped wiring harness connections into ERIM(port engine would run off of starboard output) and then port would go to emergency mode. If I was running both engines at same time, they both would go to emergency mode. I have just received another ERIM(the exact one you have pictured). Have not installed it yet as boat is now winterized. You might confirm with Sturdy about your DDEC system as they told me that unit is a DDEC 2.5. It will be interesting to see what you find out as to your problem. I did not check any relay on fire boy system but will. I won't be able to install new unit until sometime in March when I re-commission her. Let us know how you make out.