Ok, for all the people out there, who are boomers, and thinking about one of these. Machinery (Think Motorhome/Trailer/Truck/car) needs to run. As a minimum all the systems in one of these need to work 2 hours a month every month of the year. If you sat in a chair for a year, you would not start either, this stuff is not rocket science, if its in storage, and you can physically get to it, start it up, run the genset to charge the batteries, turn on the water heaters, furnace, level the thing, put out the slides, run everything. No wonder it was dead. Most likely the ECM was fine, but I would imagine, the batteries were dead, severely sulfated, and it may have taken a power surge if plugged in all the time, that could have killed the ECM. They may need standby voltage all the time, so that would place a parasitic load on the batteries if not plugged in, causing them to discharge to ZERO and that might have killed it. Treat the RV like you want to treat yourself, it will last longer.
Monty & Janet - 2007 Alpine APEX 40 MDTS
S/N - 75715 - Retired - Master Certified RV Tech