MTH PS2 5V Premier Mikado, headlamp and marker flicker

Lou,  Are you doing repairs, but not a tech and coming hear for the troubleshooting?   Is there a consulting fee?

Yes there is a fix.  It is the Mux board issue that requires, some rewiring in tender, component changes on mux board and possible the blue wire addition depending on the vintage of the engine.  Was considered complex, and best done by tech to prevent damage to 5V board. G

Lou,

https://ogrforum.com/...rials-andamp-manuals

Barry explained the fix in his 3rd post down in the above. I have the 20-3055-1 with the same problem, but I never got around to fixing it.

Joe, Did you ever get my email response to your e-mail?  Never heard back.  G

GGG posted:

Lou,  Are you doing repairs, but not a tech and coming hear for the troubleshooting?   Is there a consulting fee?

Yes there is a fix.  It is the Mux board issue that requires, some rewiring in tender, component changes on mux board and possible the blue wire addition depending on the vintage of the engine.  Was considered complex, and best done by tech to prevent damage to 5V board. G

Nah. Buddy has a few locomotives I'm trying to fix for him in exchange for some stuff. This one looked like an easy fix but I'll tell him to take it in to a tech. I'm not doing component repair on a 5V board for him. This was the last of the few he wanted checked out. 

I fixed his other ones without issue. Just lights, traction tire, and speaker repairs. The Railking FEF and this one were the two puzzling ones in his "not working correctly" bunch.

The full fix is a bit involved.  Nothing super difficult, but there are some surface mount components that need to be removed/changed.  FWIW, some locomotives respond to just doing the first step, others you have to do the entire procedure.

I'll try swapping the two blue wires. If it doesn't work I'll tell him to take it to a tech for the board component replacement. 

After that it's back to working on my junk.