Jumpy unit and signal loss?

I'd start with thoroughly cleaning the wheels and rollers on these two engines before moving on to something else.

Thanks Richie, that certainly is a good place to start and can only help. I have cleaned the wheels before and this may have improved signal reception a bit (if in fact that is the issue?) I guess I will find out after I leave them on display for a bit and try to run in future.  I hesitate to open them up as no idea what to look for?  In any event I can live with it, just so odd and only these engines seem to have the issue (I own about 15 TMCC locos), and they have done this every time they sit for say a month.....

There is the possibility of the specs for one or more components on the boards are not within specs until the subject component(s) gets to a temperature that brings the component(s) into spec.  Only by swapping boards until correct functioning is achieved would be the only trouble shooting, I would consider.  My $.02.

Thanks Jim, I had not considered that....quite possible.

I’d make sure the pickup rollers are clean, not only their surfaces that touch the rail, but especially their roller axles since these are older locos. If you have any track cleaning fluid., a drop on both axle ends should do. I usually spin the rollers at high speed with my Dremel tool to more thoroughly clean the axles.

Many TMCC locomotives that have been around for ten to twenty years have developed a bit of oxidation on connector pins.  The simple fix is to reseat all the boards and connectors.  If it's only sound, the older RailSounds board through Railsounds 5.5 had two PLCC chips in sockets, it's very common for those pins to develop oxidation and have a poor contact.  Using a PLCC extraction tool, you can just slide them out a bit and reseat them, job done.

Hi GRJ,

You have been right too many times for me to not give your explanations a credible foundation.  However, if there was oxidation on the board connectors or dirt on the rolls or track, that would be more of a consistent issue.  However, Doug (DMBX) states the issues are eliminated after a period of time.  This in my mind would be a component temperature issue.  I do firmly believe that the suggested remedies suggested by you and others should be acted on as they are easy remedies if they are the cause of the issues experienced by Doug (DMBX).  My $.02

Well, swapping boards will accomplish what I suggested, reseating the connections!   However, it's even easier to do what I suggest, no new boards need to be in the picture.  I've seen lots of engines over the years that exhibit temperature sensitivity, and a majority (but clearly not all) the time it was simply poor connections.  Remember, as the engine warms up, things expand, including connectors and their pins.

I have seen a number of temperature sensitive components cause similar issues as well, and I didn't dismiss your observations, just added another possibility.

Thanks guys I appreciate all your thoughts. I think I will just give the units a good cleaning and live with it for now....I mean letting the locos warm up before a show (when they are allowed again?) is not such a big deal.  Despite the occassional issues I must say most of the fleet have been reliable performers.  I guess just like the real deal - motive power issues can happen😉