After a couple weeks of reading here about "No WIU/TIU Found", various other connection errors, removing apps, resetting WIU, changing from Apple to Android and back again, ripping up track and a dozen other things, I have finally isolated the lone culprit: one PS2 engine. I had moved the WIU and TUI to a test track a couple times where every other MTH engine was "found" and ran without a problem. Until, that is, I tried to run MTH # 20-2952-1 and voila: back to error messages. Once this rabid engine triggers those error messages, nothing runs until I shut it all down and walk away for a while.
I may have mis-diagnosed it to be the TIU and not the WIU, but I get a once-per-second continuous pink blink on the WIU so long as everything is powered. I am using the 18V aux power. Not the transformer. My instinct then tells me the WIU does see the TIU but the TUI has choked on that single engine. Either way, if I set that one loco off to the side, all my other engines work fine. This particular locomotive had been running without a problem since I bought it last summer. Never an issue with it until now. It does run conventional as it should but trying to run command is off the map.
I can't do a factory reset on this engine using the WIU and an APP because nothing will find the engine. Sorry if my post jumps around somewhat randomly. I have tried to explain all the things that may be asked in advance. Should I take it to a shop that has a DCS remote? Or will they likewise not find the engine?
Thanks to all !