Three layouts in Lionel 6-24295 stopped working but building still lights

[gunrunnerjohn]

I saw this answered over in the OGR forums, and their answer looked to be the right one.  Have you replaced the diodes mentioned?

[mrmet6986]

I have the Lionel 6-24295 Cowen's Corner Hobby shop hooked up to the accessory terminals of a small Tyco transformer with an on/off switch powering the transformer on and off. The building has been hooked up and working fine for several years now and has been run minimally. Today I noticed that the building lights were all functional but that the three operating train layouts in the building were not. I checked the wiring and transformer. The transformer had only been powered on for a maybe ten or so minutes but was extremely hot to the touch (small Tyco transformer I used just for this accessory nothing else is connected to it). I swapped out transformers checking all wiring and connection. But I am still seeing the same behavior.
Has anyone had this problem before? Any ideas where to start troubleshooting?