I probably should not say anything but I've been having some problems with my O Gauge trains. I'm starting to think maybe it's the heat. My train layout is out in my garage and I live in Florida. It's really hot here. Summers the garage is like an oven. I just got some repairs done by MTH F3 and put in a new smoke unit in my Lionel Mikado.  Sense then I bring all my engines that have computer chips in them inside. I keep them inside. Take them out in the garage in the early morning for an hour but when done running trains the engines come back inside the house?

Just food for thought. Was your Mikado stored in a area with high heat. I'm a retired software engineer and my passed computer knowledge says heat can play rough on computer chips?

jack