I'm not sure what exactly has happened with one of my transplants,Circuit boards from a cheapy PRR 2-8-0 were transplanted a few years ago into a Williams GP-9. The engine has run fine for years but derailed and now won't move in either direction.
Ok I'll do a feature reset. no difference. still won't move, but everything else works...... Ok a factory reset.... Still won't move but the custom name is gone and the factory name appears" PRR 2-8-0" after a re-add. Everything works but that darn thing still won't move.... I know for a fact that a proto-2 will run without a battery but I happened to have a brand new8.4 volt MTH battery(green) handy so i replaced the battery and guess what , the engine runs fine .So what's the point of my post..... I believe a dead battery is worse than none at all in command and can lead to all sorts of problems. This is the first time I've run across this type of failure.
I know the battery needs to be up to par for conventional (this one was dead as a door nail) but never suspected it would affect command operations. I believe the feature reset should have fixed the engine at least until power from the track was turned off. Nope!!